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Tektronix 070-8811-08 Computer Monitor User Manual

1. Level Meters Display Mode 4 Channels Interpolation ON Scale amp Ballistics TRUE PEAK Peak hold time sec 2 Peak Program Level dBFS 3 Test Level ABFS 18 Ch 1 2 and Sum amp Diff Set 0 dB Mark to 4 Channels DGT FULL SCALE dBFs Consecutive FS Samples for CLIP 1 Ch 3 4 and Sum amp Diff Consecutive 0 Samples for MUTE 10 CLIP MUTE hold time sec 2 Ignore Validity Bit No Suppress Sync Loss Flag No TOP MENU Press MENU CLEAR for additional information CU J Figure 18 The Level Meters submenu 5 Again use the multi function knob to scroll the menu highlight to the parameter you wish to configure The soft button assignments will change to reflect your choice of settings For menu items that have numeric settings the top two soft buttons become increment decrement controls designated with up and down arrow icons as represented in Figure 19 Level Meters Display Mode 4 Channels Interpolation ON A Scale amp Ballistics TRUE PEAK 2 Peak Program Level dBFS 8 Test Level dBFS 18 h A Set 0 dB Mark to Figure 19 Soft buttons and numeric settings 6 Press the soft button that corresponds to the desired setting or that increments or decrements the numeric value A numeric value will continue to increase or decrease as long as you hold 24 764 Digital Audio Monitor User Manual Operating Basics the button down or until you re
2. Service Submenu Use the Service submenu Table 14 to select patterns for use in adjusting the display find the version of software installed in the instrument and the instrument s firmware identification number and superimpose a numeric readout of signal levels on the Session display Refer to the 764 service manual for more information Table 14 Service submenu Item Choices Factory setting Adjustment MONITOR CROSS not applicable HATCH Information SOFTWARE VERSION _ not applicable IDENTIFICATION NUM Numeric Level Readout OFF ON OFF Adjustment Once you choose this item you can cycle through the four available test patterns by repeatedly pressing the top soft button Patterns are used in adjusting the display during manufacture Information Press the appropriate soft button to access the corre sponding information Numeric Level Readout This readout is intended for use in manufac ture only it obscures a large part of the Session display 764 Digital Audio Monitor User Manual 61 Reference Using the RS 232 Port The primary use of the 764 RS 232 port is to output session reports The reports can be sent directly to any ASCII printer with serial input or captured on a PC and saved to disk The RS 232 port also supports remote control of 764 Digital Audio Monitors with serial number BO20000 and higher To control the instrument from a personal computer or ASCII terminal connect it as discu
3. Operating Basics The short report shown in Figure 26 is a record of what happened during the session It contains a print out of the statistics tabulated on the 764 Session display and lists several instrument settings that can affect meter behavior In addition to all the information in the short report the long report contains time stamped peak and error data and gives more detail about active bits DC offset and sample rates Figure 27 is an example of the additional information contained in a long report Highest True Peak Reading within each 20 second interval Channel 1 Channel 2 Channel 3 Channel 4 Session dBFS Session dBFS Session dBFS Session dBFS 00 00 09 10 8 00 00 09 8 1 00 00 11 8 1 00 00 12 8 1 00 00 31 4 9 00 00 31 0 00 00 31 0 00 00 31 0 Highest Bar Reading within each 20 second interval Channel 1 Channel 2 Channel 3 Channel 4 Session dBFS Session dBFS Session dBFS Session dBFS 00 00 10 13 6 00 00 10 12 1 00 00 12 12 1 00 00 12 12 1 00 00 31 4 9 00 00 31 0 00 00 30 0 00 00 30 0 Mutes Found Channel 1 Channel 2 Channel 3 Channel 4 Session Session Session Session 00 00 32 00 00 32 00 00 37 00 00 37 Code Violations Found Channel 1 Channel 2 Channel 3 Channel 4 Session Session Session Session 00 00 17 00 00 17 00 00 36 00 00 36 Number of Active Bits Channel 1 Channel 2 Channel 3 Channel 4 Minimum Bits Minimum Bits Minimum Bits Minimum Bits 00 00 13 0 00 00 13 0 00 00 13 0 00 00 13 0 Max
4. CHAN soft button to toggle between the two input channel pairs 1 amp 2 and 3 amp 4 CHANNEL STATUS Channel 1 Channel 2 Channel use professional professional Data use audio audio Emphasis no emphasis no emphasis Locking of source locked locked Sample frequency 48 kHz 48 kHz Channel mode 2 channel 2 channel User bits mode not indicated not indicated AUX bits use main audio main audio Audio word length not indicated not indicated Reference signal not a ref Origin AM70 Destination EFGH Sample number 0 Time of day 00 00 00 00 Block CRC i i is valid CLEAR N Figure 28 The Channel Status view text mode 764 Digital Audio Monitor User Manual 37 Operating Basics m In binary display mode illustrated in Figure 29 you may turn the multi function knob to highlight various bits or blocks of bits for same screen plain English decoding For example bits 3 through 5 of byte 0 indicate the pre emphasis if any that has been applied to the audio program when you move the screen highlight to those bits the type of emphasis will be displayed in decoded text near the bottom of the screen Only one channel at a time is shown in binary mode the selected channel is indicated on the top line of the display Press the CHAN soft button repeatedly to cycle among the four input channels m The Xmsn Order Binary display reverses the bit order to correspo
5. Specifications table Refer to the EMC specification published for the stated products May not meet the intent of the Directive if used with other products Emissions comply with FCC Code of Federal Regulations 47 Part 15 Subpart B Class A Limits 764 Digital Audio Monitor User Manual Appendix A Specifications Table 29 Certifications and compliances Cont Australia New Complies with EMC provision of Radiocommunications Act per Zealand Declaration the following standard s of Conformity EMC AN NZS 2064 1 2 Industrial Scientific and Medical Equipment 1992 EC Declaration of Compliance was demonstrated to the following specification as Conformity Low listed in the Official J ournal of the European Communities Voltage Low Voltage Directive 73 23 EEC Amended by 93 68 EEC EN 61010 1 1993 Safety requirements for electrical equipment for measurement control and laboratory use Approvals UL3111 1 Standard for electrical measuring and test equipment CAN CSA C22 2 No 1010 1 Safety requirements for electrical equipment for measurement control and laboratory use Installation Category Terminals on this product may have different installation category Descriptions designations The installation categories are CAT III Distribution level mains usually permanently connected Equipment at this level is typically in a fixed industrial location CAT II Local level mains wall sockets Equipment at this l
6. 8 dB in some organizations above the alignment level A practical way of configuring the 764 to implement the above recommendation with PPM ballistics is to set the Test Level to the EBU recommended alignment level of 18dBFS and set the Peak Program Level to the permitted maximum level of 9 dBFS or 10 dBFS You may choose to set the 0 dB mark to either the Peak Program Level or Digital Full Scale With the 764 the true peaks are 764 Digital Audio Monitor User Manual 43 Reference 44 always indicated by the peak segment so actual headroom is always visible With VU ballistics the Test Level should correspond to the same level as above 18 dBFS if program exchange is important In accordance with standard practice the Test Level line up level corresponds to 0 VU so you may set the 0 dB mark to the Test Level If program material is then peaked at 0 dB you can expect actual peaks to be 8 to 14 dB higher which can be easily seen with the true peak indicators of the 764 A good setting for the Peak Program Level would be in the range of 8 to 10 dBFS IEEE 152 1991 recommends that the VU meter readings of program material be 8 dB below those of a PPM meter to get the same actual program level The above setup accomplishes that All of the above is for standardizing digital recordings or digital transmissions for international program exchange Individual organizations may have their own internal standa
7. CLEAR MENU button to exit the menu hierarchy then press VIEW AUDIO if necessary to select the audio Phase or Session display Notice that sixteen diamonds arranged in four groups of four now occupy the top of the display as shown in Figure 37 The diamonds represent the four groups of four audio channels defined in SMPTE 272M Bright diamonds indicate active channels a white underline indicates the channel group that you have selected through the Input submenu The numbers of the selected channels appear under the meter bars Tek PPM Peak dBFS Session 00 00 00 00 Run KA SESSION STATISTICS Channel 5 7 8 Highest true pk nil il nil nil dBFS Highest bar rdg nil nil nil nil dBFS No of clips 0 No of mutes 0 Invalid samples O Parity Errors n a n a n a Code violations n a n a n a n a Active Bits o 0 oOo 0 DC offset nil nil nil nil dBFS Sample rate 00 00 00 00 kHz FrameSyncErr n a na Figure 37 The Audio view with digital video input selected 7 If there is no audio on one or more of the channels in the selected group the message NOT PRESENT now occupies the meter bars of the inactive channels If necessary repeat steps 2 3 and 5 764 Digital Audio Monitor User Manual 91 Appendix C Options 92 above to select a group with active audio channels then press CLEAR MENU to return to the audio view Configure the Meters Once you have selected the correct channel group you can configure the level meter
8. CLIP MUTE hold time Ignore Validity Bit No Suppress Sync Loss F to clear the HELP message HELP This is the TOP MENU The list of submenus is on the left Turn the multi function knob to move the highlight up and down the list SUBMENU boxes list the items within the highlighted submenu and show the current settings Press any soft button to enter the highlighted submenu Press the CLEAR MENU button to resume nor mal operation Figure 9 The top menu HELP message 3 The knob icon appears in the upper right corner of the display when the multi function knob is active Here you may turn the knob to scroll among the TOP MENU choices Turn the knob now to scroll the menu highlight to the Inputs entry as shown in Figure 10 764 Digital Audio Monitor User Manual Getting Started SUBMENU CH 1 2 Input XLR balanced CH 3 4 Input XLR balanced Reference Input XLR balanced Level Meters De emphasis Phase Display Headphones Time Code Serial Port Save Setups Restore Setups Screen Saver Service SUBMENU Press MENU Ir f CLEAR for additional information C L L I J Figure 10 Selecting from the top menu 4 The five buttons immediately to the right of the display are called soft buttons The printed molded lines to the left of these buttons serve to associate the buttons with on screen menu choices or functions In Figure 10 the bottom soft button is associated with
9. Location In bar The 764 is not locked to an incoming signal on the indicated input channel Data cannot be decoded all data and all other errors are ignored Likely causes of this message include missing input signal incorrect setting s in the Inputs submenu or inadequate or defective input signal s The INPUT UNLOCKED indicator persists for the CLIP MUTE Hold Time set through the Level Meters submenu Interpolation OFF Location Audio View below meter bars may be obscured by other error Messages Interpolation has been turned OFF through the Level Meters submenu This message will persist until Interpolation is returned to the factory default setting of ON LOW CONF Location In bar Low Confidence This warning message Indicates a marginal signal on the serial digital interface Problems that can trigger this message such as significant jitter or low signal amplitude will usually result in a poor eye pattern when the serial digital signal is displayed on appropriate equipment The LOW CONFidence indicator persists for the CLIP MUTE Hold Time set through the Level Meters submenu 764 Digital Audio Monitor User Manual 85 Appendix B Error Warning Messages 86 MUTE Location In bar The MUTE indicator flashes when the digital audio data on the input channel remains at zero value for n or more consecutive samples The factory default value of n is ten 10 it may be changed throu
10. Location In bar The incoming subframe does not have even parity as specified by the applicable digital audio standards The data sample is unreliable and is ignored The meter bars and phase pattern treat the sample as a zero sample The PARITY indicator persists for the CLIP MUTE Hold Time set through the Level Meters submenu When a Session is running the instrument counts parity errors and displays the current total on the Session display SYNC ERR Location Audio View below the affected meter pair 1 2 or 3 4 Either the input is out of synchronization with the REFERENCE input signal by at least 25 of the digital audio sample frame or the input to reference timing is constantly changing due to mismatched sampling frequencies When the 764 is not locked to an incoming signal on the REF ERENCE input the presence of this flag below the channel 3 4 meter bars indicates that the two inputs CH 1 2 and CH 3 4 are out of sync with each other Again the signals can be mistimed by a quarter frame or more or be sliding relative to one another due to a sample frequency mismatch 764 Digital Audio Monitor User Manual 87 Appendix B Error Warning Messages To determine the exact cause of a SYNC ERR flag select the 764 Session display and check the Sample Rate and Frame Sync Err fields in the SESSION STATISTICS panel See The Session Display on page 29 for more information The flag will persist until synchr
11. RESET Session soft button 30 Restore Setups submenu 40 60 RS 232 communications port 6 62 S Save Setups submenu 40 59 Screen Saver submenu 60 Serial Port submenu 58 Serial video loop through 7 Service submenu 61 Service Support xii session Copy soft button 30 display 29 maximum duration 59 reports 34 RESET soft button 30 statistics 30 time 29 SESSION button 16 764 Digital Audio Monitor User Manual session display running stopped indicator 30 session time 29 Setups saving and restoring 40 SMPTE RP 155 90 44 soft buttons 11 Specifications 75 Standby mode 8 submenus De emphasis 53 Headphones 48 56 Inputs 56 Level Meters 48 phase display 54 Restore Setups 40 60 Save Setups 40 59 Screen Saver 60 Serial Port 58 Service 61 Time Code 57 sum and difference bars 18 20 25 Support product xii service Xil SYNC ERR Flag illustrated 32 suppress 52 T TERM switches 3 test level 20 43 51 Time Code inputs 5 submenu 57 true peak indicator turn Off 51 105 Index U W User Data view 15 39 warning messages V Validity Bit ignore 52 VGA video output 5 VIEW buttons 16 Views Audio 13 Channel Status 15 User Data 15 VOLUME knob 18 VU meter ballistics 44 106 CODE ERR 45 84 Interpolation OFF 50 LOW CONF 45 85 MUTE 21 NO INPUT 44 85 86 No Video Input 92 NOT PRESENT 93 PARITY 45 87 SYNC ERR 32 52 V BIT 46 8
12. echo off your command entry will not appear on the computer or terminal display ECHO Displays the current state of ECHO on or off ECHO Displays the syntax of the ECHO ON OFF command RESET Resets the instrument to a power up state 764 Digital Audio Monitor User Manual 67 Reference Table 16 General remote control commands Cont Command Effect MSGON lt text gt Displays a temporary message up to 58 charac ters on the top line of the 764 display Excess text does not wrap itis truncated MSGOFF Removes the temporary message SYSTEM ERROR Returns the last command error SYSTEM ERROR CLEAR Clears the last command error GET Commands GET commands retrieve information from the 764 Table 17 lists and explains the GET commands SYNTAX GET mnemonic lt number gt no number or invalid number returns all selections for the mnemonic Table 17 Remote control GET commands 1 Ch 3 4 input GET BARFLAG lt 0 3 gt 0 Meter bar 1 Bar flags 1 Meter bar 2 Command Retrieves GET Lists all the GET commands GET mnemonic none All the values for the command mnemonic GET TIME none Current Session LTC or VITC time GET FRAME lt 0 1 gt 0 Ch 1 2 input Frame Sync Errors 1 Ch 3 4 input GET SAMPR lt 0 1 gt 0 Ch 1 2 input Sample rate 1 Ch 3 4 input GET RAWSR lt 0 1 gt 0 Ch 1 2 input Raw sample rate 1 Ch 3 4 input GET ERRFLAG lt 0 1 gt 0 Ch 1 2 input Error flags 2 Meter bar 3 3 Meter bar 4 68 764 Digit
13. output a Session report do so before you reset the Ses sion Copy soft button is present when SHORT REPORT or LONG REPORT has been selected through the Serial Port submenu and the session has been stopped but not reset Press the soft button to output a session report to an attached printer or personal comput er Refer to Session Reports beginning on page 34 for more information 5 Session Statistics The session display reports these values for the four input channels m Highest true peak in the session It is equal to the highest peak indicator reading on the corresponding level meter and does not depend on the meter Scale amp Ballistics selected through the Level Meters submenu m Highest meter bar reading bar rdg of the session This corresponds to the highest reading of the meter bar which for a given audio program may depend on the meter Scale amp Ballistics selected through the Level Meters submenu 764 Digital Audio Monitor User Manual Operating Basics m Number of CLIPs detected during the session This is directly affected by the Consecutive FS Samples for CLIP setting in the Level Meters submenu m Number of MUTEs detected during the session Affected by the Consecutive 0 Samples for Mute setting in the Level Meters submenu Number of invalid samples encountered during the session The 764 counts a sample as invalid when its validity bit is set high All these
14. portion of the meter bar above the level will also be red Test Level Test level is also known as Reference level or Line up level The diamond shaped Test level marker will be yellow on an external color display and the part of the meter bar between this level and Peak Program level will also be yellow The default test level is 18 dBFS it may be set to any integer between 0 and 30 dBFS Variable scale The scale range and offset may be adjusted through the METER SCALE EXPAND and OFFSET buttons This feature lets you more closely monitor program levels in a selected portion of the meter such as immediately above and below the Test level To adjust either the range or offset press the appropri ate button then turn the multi function knob Press METER SCALE NORMAL to restore the default meter scale m The normal range is 70 dB 0 dBFS to 70 dBFS custom range may be as little as 10 dB or as great as 90 dB 764 Digital Audio Monitor User Manual Operating Basics m Shape The upper 20 dB of the scale is linear in dB the scale is progressively compressed below 20 dBFS m The upper limit of the meter scale is the anchor for expansion and compression that is the top scale number remains the same when you expand or compress the scale m The lower limit bottom of the scale cannot be adjusted below 90 dBFS the upper limit top cannot be higher than 0 dBFS or lower than 20 dBFS 6 Mute indicator and oth
15. the factory setting 60 seconds is used Choose an interval that is appropriate to your situation be aware that the 764 can store enough peak data to fill over 70 pages of text NOTE To prevent unexpected results change this setting immediately after a session reset only and not during a session Save Setups Submenu Save the current instrument configuration through the Save Setups submenu Table 11 The current settings will overwrite any configuration previously saved in the Setup Table 11 Save Setups submenu Item Factory setting Selection SETUP 1 not applicable SETUP 2 SETUP 3 764 Digital Audio Monitor User Manual 59 Reference 60 Restore Setups Submenu Restore a previously saved instrument configuration through the Restore Setups submenu Table 12 The current instrument settings will be replaced by those in the saved Setup Table 12 Restore Setups submenu Item Factory setting Selection SETUP 1 not applicable SETUP 2 SETUP 3 FACTORY SETUP Screen Saver Submenu Select a suitable delay in the Screen Saver submenu Table 13 to help prevent display burn in Choose an interval long enough to prevent activation during program monitoring When the screen saver is active press any button to restore the normal display Table 13 Screen Saver submenu Item Factory setting Delay in Hours OFF 1 2 23 hours OFF 764 Digital Audio Monitor User Manual Reference
16. user manual m A power cord Any cabinet ordered with the instrument is shipped in a separate carton Mechanical Installation To accommodate the installation needs of users worldwide Tektronix provides the 764 without an enclosure cabinet To ensure proper cooling electromagnetic shielding and protection against accidental electrical shock install the instrument in the Tektronix enclosure that best suits your application NOTE The Tektronix 764 meets EMI EMC standards when shielded interconnect cables are used and when installed in one of the following Tektronix enclosures 1700F00 Plain cabinet for 1 2 rack width m 1 700F02 Portable cabinet including feet and handle m 1700F05 Dual side by side rackmount adapter 764 Digital Audio Monitor User Manual Getting Started Order the appropriate enclosure through your nearest Tektronix field office or representative enclosures without first installing the cabinet mounting screws as shown in Figure 2 Without the mounting screws an instrument can slip out of its cabinet if tipped forward Property damage or injury may result T WARNING Do not carry an instrument in one of the optional Figure 2 Rear view of the 764 in a Tektronix enclosure Connecting the 764 to Your System Except for the headphone jack all connectors are on the rear panel of the 764 shown in Figure 3 The connections you make will depend on your particular installat
17. 3 Appendix C Options Option 02 instruments are set during manufacture for fixed output refer to Configuring the Output on page 95 for information about changing the setting When outputting to an unbalanced load 0 to 2 0 Vrms variable output only you must connect one of the lines to ground refer to Connecting the Instrument on page 97 for more information m The analog outputs supercede the digital XLR loop throughs always leave the TERM switches of Option 02 instruments set to 110 Q for proper XLR input termination Table 31 lists and describes important Option 02 characteristics Table 31 Option 02 characteristics Characteristic Output Level Fixed gain Variable gain high output Variable gain low output Output impedance typical Frequency Response Distortion THD N Distortion typical THD N variable gain high output 94 Description With 0 dBFS 1 kHz sine wave applied to the input 24 dBm 1 6 0 0 dBm into 600 Q balanced 24 dBm volume control fully clockwise into 600 Q balanced 2 0 Vrms volume control fully clockwise into gt 10 kQ 50 Q 2 dB 20 Hz to 20 kHz lt 0 05 22 kHz THD N bandwidth lt 0 005 at 1 kHz control fully clockwise load 210 kQ 22 kHz THD N bandwidth 764 Digital Audio Monitor User Manual Appendix C Options A Configuring the Output Qualified service personnel can change the output configuration with the following procedure CAUTION The 76
18. 3 of mutes Invalid O 11 samples o 0 Parity Errors o 0 Code violations O QO Active Bits 20 20 DC offset 85 85 Sample rate 44 10 Frame Sync Err 0 0 CLEAR MENU Figure 20 Sum and difference bars and the session display The Phase Display The 764 Phase display is a Lissajous pattern display augmented with a phase Correlation meter It is designed for convenient qualitative monitoring of the phase relationship between any two input channels The Phase display always uses interpolated 4X oversampled data even if interpolation is turned off in the level meters submenu You can set the instrument for either Soundstage or X Y orientation of the Lissajous pattern as illustrated in Figure 21 NOTE The orientation of the Lissajous pattern phase channel pairings and Correlation meter speed see below are selected through the Phase Display submenu Please see page 54 in the Reference section of this manual for details 26 764 Digital Audio Monitor User Manual Operating Basics in phase Phase display A AGC On Koli Phase display A AGC On Koji Soundstage Orientation X Y Orientation Figure 21 The 764 phase display The Lissajous Pattern The Lissajous portion of the phase display is a plot of one channel against another on an orthogonal pair of axes The X Y orienta tion shown on the right in Figure 21 plots left channel data along the vertical axis and right channe
19. 4 contains static sensitive components The following procedure should be performed by qualified technicians only 1 Disconnect power and all other connections from the 764 rear panel and then remove the instrument from its enclosure The Analog Line Output circuit board assembly is mounted horizontally above the audio XLR connectors at the rear of the chassis The configuration jumper pins are readily accessible on the top surface of the board 2 Identify the jumper configuration in Table 32 that corresponds to the desired output add and remove jumpers to from the jumper pin pairs to achieve that configuration Pin pairs J20 J21 J22 and J23 are provided as a convenient place to park unused jumpers If you need additional jumpers for the new configura tion take them from J20 J23 if you have extra jumpers after reconfiguration put them onto J20 J23 Table 32 Output configuration jumper locations Output Jumper configuration AES connector Fixed 24 dBm Variable to 24 dBm Variable to 2 0 VR ms J4 J7 J8 J6 J5 J15 J16 J18 J17 i See configuration procedure step 3 764 Digital Audio Monitor User Manual 95 Appendix C Options 3 Locate J913 and J914 the two rows of six connector pins on the AES circuit board assembly The AES board is on the right side of the 764 when you view the instrument from the rear panel J913 and J914 are near the end of the AES board that is closest to the front of the instr
20. 8 764 Digital Audio Monitor User Manual
21. A 13 P AU 764 Digital Audio Monitor User Manual Reference The example command gets the time gets the sample rate from the Channel 3 Channel 4 input and presses the View Audio button When you abbreviate a command you cannot leave out letters in the middle of a command argument If the complete argument is needed to make a command unique all the argument alphanumerics must all be used For example PRESS SKEY5 can be abbreviated as p skey5 but the complete argument is necessary The unique letter or number is the last one of the argument If you send an abbreviated argument that is not unique the first command in the list that is recognized is done If you send a command with unrecognized syntax an error message is displayed showing the incorrect command If you are in doubt about an abbreviation use the entire argument General Commands Table 16 lists and explains the general or miscellaneous 764 remote control commands Table 16 General remote control commands Command Effect HELP Displays the list of remote commands KNOB UP lt l 10 gt Scrolls up a menu or data list by the specified number of positions or turns the knob one incre ment up KNOB DOWN lt 1 10 gt Scrolls down a menu or data list by the specified number of positions or turns the knob one incre ment down KNOB Displays the syntax for the KNOB command ECHO ON Turns command echo on echo on is the default ECHO OFF Turns command
22. Digital Audio Monitor User Manual Contents Table 8 Option 01 input submenu video inputs selected 57 Table 9 Time Code submenu 44 43 405 lt 34 49es4 45 045448 57 Table 10 Serial Port submenu items 58 Table 11 Save Setups submenu 2240c000y ceased eves 59 Table 12 Restore Setups submenu 4 60 Table 13 Screen Saver submenu 4 5 60 Table 14 Service submenu 6 s0k veg koa eo a eae we erkews 61 Table 15 RS 232 pin assignments 20 5 62 Table 16 General remote control commands 67 Table 17 Remote control GET commands 68 Table 18 Remote control PRESS commands 70 Table 19 Remote control MENU commands 71 Table 20 Digital audio inputs 2 s45sasesdesasecavee es 75 Table 21 Level Meters and Phase Display 76 Table 22 SMPTE Time Code inputs os 25 ee eee dant 76 Table 23 Interface parameter measurements 76 Table 24 Headphone output 0200000 71 Table 25 VGA OUtPU irere nia eed ha gidere ens 11 Table 26 Physical characteristics 0 5 78 Table 27 Power requirements 00e ee eee 79 Table 28 Environmental characteristics 79 Table 29 Certifications and compliances 80 Table 30 Option 01 characteristics 0055 89 Table 31 Option 02 characteristics 0005 94 Table 32 Output
23. S SKEY5 PRESS USER 70 Equivalent button Lists all the PRESS commands PHASE DISPLAY A VIEW AUDIO PHASE DISPLAY B VIEW CH STATUS CLEAR MENU METER SCALE CUSTOM METER SCALE EXPAND METER SCALE NORMAL MENU METER SCALE OFFSET VIEW OTHER PHASE DISPLAY SESSION Soft Button 1 top Soft Button 2 Soft Button 3 Soft Button 4 Soft Button 5 bottom VIEW USER DATA 764 Digital Audio Monitor User Manual Reference MENU Commands Use the MENU commands listed in Table 19 to make selections from the 764 on screen menus The menus need not be visible on the display to change a setting with a MENU command SYNTAX MENU mnemonic lt number gt unrecognized number returns Out Of Range Error Table 19 Remote control MENU commands Command Value setting Submenu item MENU Lists the Menu commands MENU mnemonic Lists the command syntax for the queried mnemonic and gives the current setting MENU DISMODE lt 0 2 gt 0 4 Channels Level Meters Display Mode 1 Ch 1 2 Sum amp Diff 2 Ch 3 4 Sum amp Diff MENU INTERP lt 0 1 gt Level Meters Interpolation MENU BALLIST lt 0 2 gt 0 True Peak Level Meters Ballistics 1 PPM 2 E xtended VU MENU PHTIME lt 0 10 gt 0 to 10 seconds Level Meters Peak Hold Time MENU PPGMLVL lt 30 0 gt 30 to 0 dBFS Level Meters Peak Program Level MENU TESTLVL lt 30 0 gt 30to 0 dBFS Level Meters Test Level MENU ZERODB lt 0 2 gt 0 Dgt Full Scale dBFS Leve
24. The following numbered paragraphs correspond to the numbered features visible in Figure 23 1 Time readout in hours minutes seconds frames By default this is Session time Session time is the time elapsed since the session was started or since the most recent session reset You can set the 764 through the Time Code submenu to display VITC Verti cal Interval Time Code or LTC Linear Time Code in place of 764 Digital Audio Monitor User Manual 29 Operating Basics 30 Session time The instrument time stamps any errors encountered during the Session with the chosen time code the information is saved in NVRAM for use when you output a Session report refer to page 34 2 Run ning Stop ped indicator and soft button assignment This indicator is associated with the top soft button immediately be low the MENU button The current state is highlighted Run means that the Session is running and statistics are accumulating Stop means that the Session has been suspended or stopped Press the soft button to toggle the Session between Run ning and Stop ped 3 Session Statistics explained below 4 RESET Session indicator and soft button assignment This indica tor is visible only when the Session is stopped Press the associated soft button immediately above CLEAR MENU to reset all Session statistics to 0 or blank unknown Note that a Session reset erases all Session statistics from memory if you plan to
25. User Manual Tektronix ri 764 Digital Audio Monitor Serial Number B020000 and Above 070 8811 08 This document supports firmware version 2 1 and above www tektronix com Copyright Tektronix Inc All rights reserved Tektronix products are covered by U S and foreign patents issued and pending Information in this publication supercedes that in all previously published material Specifications and price change privileges reserved Tektronix Inc P O Box 500 Beaverton OR 97077 TEKTRONIX and TEK are registered trademarks of Tektronix Inc Warranty Tektronix warrants that the 764 Digital Audio Monitor will be free from defects in materials and workmanship for a period of one 1 year from the date of shipment If any such product proves defective during this warranty period Tektronix at its option either will repair the defective product without charge for parts and labor or will pro vide a replacement in exchange for the defective product In order to obtain service under this warranty Customer must notify Tektronix of the defect before the expiration of the warranty period and make suitable arrangements for the performance of service Cus tomer shall be responsible for packaging and shipping the defective product to the service center designated by Tektronix with shipping charges prepaid Tektronix shall pay for the return of the product to Customer if the shipment is to a location within the country in whi
26. User Manual 49 Reference 50 or channels 3 4 the right hand bars show L R 2 Sum and L R 2 Diff data derived from the two left hand bars The Sum and Difference bars use the same scale and ballistics and all other settings as the channel level meters Interpolation When interpolation is OFF the 764 level meters measure the digital input data only When interpolation is ON the instrument also measures interpolated data generated by a 4X oversampling filter Select OFF to see the levels encountered by the digital equipment such as recorders processors and transmitters in your system Choose ON to see a more accurate representation of the levels in the reconstructed analog audio program A display message immediately below the level meters reminds you when Interpolation is set to OFF see Figure 33 Figure 33 The interpolation OFF message Ballistics Use the Ballistics item to configure the dynamic response of the level meters to conform to one of three standards m PPM peak program meter which shows quasi peak levels as defined in IEEE Std 152 1991 and IEC 268 10a When PPM ballistics are selected the meters also contain true peak indicators and the display designation is PPM Peak m True Peak which shows actual signal peaks regardless of their duration Rise and Fall times are essentially instantaneous although the in bar peak indicator will persist at program peaks for
27. ach an adjustment limit Changes are confirmed by changed text after the parameter name in the submenu column on the left side of the screen 7 Repeat steps 5 and 6 until you have configured the meters to suit your needs 8 Press the TOP MENU soft button to return to the top menu or press CLEAR MENU to exit the menus and resume normal operation Sum and Difference Bars When Sum and Difference bars are selected the two left hand bars show the levels of one input pair either channels 1 and 2 or channels 3 and 4 and the right hand bars emulate the sum and difference bars of an analog audio monitor such the Tektronix 760 Note that the sum is actually one half of the sum of the left and right channel data while the difference is one half of the difference between the channels That is m LER Dif LZR 2 2 The Sum and Difference bars use the same scale and ballistics and all other settings as the channel level meters Session statis tics other than sum and difference peaks are not accumulated for the Sum and Difference bars because they would be either meaningless or redundant See Figure 20 and The Session Display beginning on page 29 for more information 764 Digital Audio Monitor User Manual 25 Operating Basics PPM Peak Session 00 00 00 00 Run BAA SESSION STATISTICS Channel 3 4 Highest true pk 6 1 4 3 5 2 18 dBFS Highest bar rdg 11 9 5 11 23 dBFS No of clips No O 2
28. al Audio Monitor User Manual Reference Table 17 Remote control GET commands Cont Command Value selection Retrieves GET WARFLAG lt 0 3 gt 0 Meter bar 1 Warning flags 1 Meter bar 2 2 Meter bar 3 3 Meter bar 4 GET CURTP lt 0 3 gt O Meter bar 1 Current true peak 1 Meter bar 2 2 Meter bar 3 3 Meter bar 4 GET SPEAK lt 0 3 gt O Meter bar 1 Session true peak 1 Meter bar 2 2 Meter bar 3 3 Meter bar 4 GET RAWTP lt 0 3 gt O Meter bar 1 Raw true peak 1 Meter bar 2 2 Meter bar 3 3 Meter bar 4 GET CURHP lt 0 3 gt O Meter bar 1 Current high peak 1 Meter bar 2 2 Meter bar 3 3 Meter bar 4 GET SHIGH lt 0 3 gt O Meter bar 1 Session high peak 1 Meter bar 2 2 Meter bar 3 3 Meter bar 4 GET RAWHP lt 0 3 gt O Meter bar 1 Raw high peak 1 Meter bar 2 2 Meter bar 3 3 Meter bar 4 GET FILESPACE File space free GET LREPORT Long session report GET SREPORT Short session report 764 Digital Audio Monitor User Manual 69 Reference PRESS Commands Each front panel button except the power switch has an equivalent PRESS lt button gt command Send the command to perform the same action as pressing the button Table 18 Remote control PRESS commands Command PRESS PRESS APH PRESS AUDIO PRESS BPH PRESS CHSTAT PRESS CLEAR PRESS CUSTOM PRESS EXPAND PRESS NORMAL PRESS MENU PRESS OFFSET PRESS OTHER PRESS SESSION PRESS SKEY1 PRESS SKEY2 PRESS SKEY3 PRESS SKEY4 PRES
29. al Left Channel 1 2 3 4 1 Manual Right Channel 1 2 3 4 2 Input Submenu Select the active connectors for the digital audio and reference inputs through this submenu Table 6 Input submenu items standard instrument Item Choices Factory setting CH 1 2 input XLR balanced XLR balanced BNC unbalanced CH 3 4 input XLR balanced XLR balanced BNC unbalanced Reference input XLR balanced XLR balanced BNC unbalanced In instruments equipped with Option 01 embedded audio input the Input submenu is changed to accommodate the additional input choice the submenu also changes depending on the chosen input Table 7 describes the input submenu in Option 01 instruments when the audio source selection is digital audio inputs Table 8 describes the submenu when digital video input is selected Please refer to Appendix C Options beginning on page 89 for more information about Option 01 764 Digital Audio Monitor User Manual Reference Table 7 Option 01 input submenu audio inputs selected Item Choices Factory setting Audio Source Digital Audio Inputs Digital Audio Inputs Digital Video Input CH 1 2 input XLR balanced XLR balanced BNC unbalanced CH 3 4 input XLR balanced XLR balanced BNC unbalanced Reference input XLR balanced XLR balanced BNC unbalanced Table 8 Option 01 input submenu video inputs selected Item Choices Factory setting Audio Source Digital Audio Inputs see Table 7 Digital Video Input C
30. and describes the available power cord options Please contact your Tektronix representative if the power cord supplied with your instrument is not correct for the local power supply Table 33 Power cord identification Plug configuration Option number North America Standard 125V 15A Plug NEMA 5 15P Europe Al 230V United Kingdom 230 V North America 230 V Switzerland 230 V 764 Digital Audio Monitor User Manual 99 Appendix C Options 100 764 Digital Audio Monitor User Manual Glossary CLIP One or more consecutive positive or negative full scale samples The actual number of consecutive samples that constitute a CLIP may be adjusted through the Level Meters submenu the factory setting is one 1 Copy Output a session report via the rear panel RS 232 port Frame Sync Err Frame synchronization error between the input pair and the reference as a percentage of the digital audio frame MUTE One or more consecutive zero samples The actual number of consecutive samples that constitute a MUTE may be adjusted through the Level Meters submenu the factory setting is ten 10 nil The measured signal level is lower than 90 dBFS Session A mode of instrument operation during which the digital audio input signals are monitored and signal data are collected Session Time The time elapsed since the beginning of the current Session True Peak The actual highest positive or negative audio sample
31. ar ance and behavior of the Audio View Phase display Table 4 Phase Display submenu Item Choices Factory setting Format LISSA OUS SOUND LISSA OUS SOUND STAGE STAGE LISSA OUS X Y Correlation Meter Speed 1 to 20 8 Pair A Leftchannelas 1 2 3 4 1 Signment Pair A Right channel 1 2 3 4 2 assignment Pair B Leftchannelas 1 2 3 4 3 signment Pair B Right channel 1 2 3 4 4 assignment Format To change the phase display format scroll to this menu choice and then press the soft button that corresponds to the desired 764 Digital Audio Monitor User Manual Reference display orientation Refer to page 26 for details on the phase display formats Correlation Meter Speed The Correlation Meter Speed setting determines how quickly the meter reacts to changes in phase relationship The meter reading is actually an average of correlation over time and this setting determines how many samples are used to calculate the average The 764 uses the fewest samples when this setting is 1 and the meter reacts almost instantaneously The instrument uses the most samples when the setting is 20 and the meter reacts much more slowly Experiment to find the setting that best fits your application For more information about this setting refer to Correlation Meter Algorithm on page 46 Pair A B Left Right channel assignment These four choices let you pair any two of the four input channels on the phase display By
32. arning messages will persist after the end of the Clip Mute or error condition For more information refer to In Bar Warning Messages beginning on page 44 Ignore Validity Bit Ignore Validity Bit determines how the instrument will react to a high value 1 validity bit in the input data In AES3 1992 digital audio a high validity bit indicates that the sample word is not suitable for conversion to audio When this item is set to the factory default of No the 764 will ignore any sample accompanied by a high validity bit display a V BIT flag in the level meter and report invalid samples on the session display and report When set to Yes invalid sample reporting will be turned Off and the instrument will treat all samples as valid Suppress Sync Loss Flags Use this setting to suppress the SYNC ERR flags and No Reference Signal message when no DAR digital audio reference is connected to the REFERENCE input or to prevent nuisance flashing of the SYNC ERR message when the input signals have differing sample rates 764 Digital Audio Monitor User Manual Reference The De emphasis Submenu The De emphasis submenu shown in Table 3 lets you select the appropriate de emphasis for each of the four input channels Enter the De emphasis submenu from the TOP menu level by scrolling the highlight to the De emphasis item and pressing a soft button Then scroll the highlight to the desired channel The four submenu it
33. as a field upgrade kit may be installed in any instrument with serial number BO20000 and above It consists of an active digital video loop through and the circuitry required to extract digital audio from 625 and 525 line Component and NTSC Composite serial digital video Option 01 instruments retain all features of the standard 764 Digital Audio Monitor Table 30 lists and describes important Option 01 characteristics Table 30 Option 01 characteristics Characteristic Description Input video formats 270 Mbit s component 625 and 525 line complying with SMPTE 259M and CCIR 656 1 143 Mbit s NTSC composite complying with SMPTE 259M Audio format SMPTE 272M level B 20 bit 48 kHz sampling rate synchronized with video Input level 800 MVp p 10 764 Digital Audio Monitor User Manual 89 Appendix C Options 90 Table 30 Option 01 characteristics Cont Characteristic Description Equalization range Proper operation with up to 19 0 dB loss at 135 MHz using coaxial cable having 1 f 2 loss characteristics with a launch amplitude of 800 mV Return loss gt 15 dB relative to 75 ohms 1 270 MHz power on input and output Output level 800 MVp p 10 Operating Information The following paragraphs explain how to monitor embedded audio with a 764 Digital Audio Monitor equipped with Option 01 Most procedures are the same as those used for monitoring digital audio with a standard instrument this section emphasizes t
34. ase see the following paragraphs for more information 70 2 3 4 Phase SYNC ERR SYNC ERR Figure 24 The SYNC ERR Flags m Frame Synchronization Error for each input with respect to the Digital Audio Reference DAR when one is present at the REFERENCE input Otherwise when both inputs are active but no DAR is present the error of input 3 4 relative to input 1 2 as depicted in Figure 25 Errors are expressed as the percentage of a complete digital audio frame Notice the No Reference Signal message in Figure 25 It will appear whenever a DAR is absent from the REFERENCE input Active Bits 24 24 24 24 DC offset 90 90 nil nil dBFS Sample rate 48 00 48 00 kHz Frame Sync Err ref 78 Figure 25 Sync Error Reporting in the Absence of a DAR The AES11 standard specifies that synchronization errors should be no greater than 25 of the audio sample frame When the synchronization error exceeds this limit a SYNC ERR flag 764 Digital Audio Monitor User Manual Operating Basics displays under the meter bars of the unsynchronized input Figure 24 shows the flags as they would appear if each input signal preceded or followed the DAR signal by more than 25 of a frame The SYNC ERR flags also appear when the input signal sample frequency varies from the reference frequency by 0 01 kHz or more Any such frequency mismatch will cause the input signal to slide relative to the reference with c
35. atches Figure 39 when the instrument is configured for variable high level output If you are using fixed output and output phase must match input phase reverse the connections to pins 2 and 3 Male XLR SY Pin 3 Pin 1 shield Pin 2 Figure 39 Standard balanced output pin assignments Low level Unbalanced Output When using low level output to drive an unbalanced load such as a consumer amplifier you must use cables that short either pin 2 or pin 3 to pin 1 the shield ground The output will not meet the distortion specification if you do not ground one of the output lines Connecting an unbalanced load as shown in either the top or bottom of Figure 40 ensures that the phase of the signal at the unbalanced input matches the phase of the 764 input 764 Digital Audio Monitor User Manual 97 Appendix C Options Analog line output XLR Receiving equipment unbalanced input Pin 3 Pin 1 shield Pin 2 Pin 2 Pin 3 Pin 1 shield Figure 40 Connecting to an unbalanced input NOTE Connecting a line to ground as shown in Figure 40 forces the analog outputs into unbalanced mode The outputs will clip above approximately 20 dBu in unbalanced mode Do not use unbalanced mode when you have configured the instrument for either fixed high level output or variable high level output 98 764 Digital Audio Monitor User Manual Appendix C Options Power Cords Table 33 lists
36. ave Setups Press any soft button to enter the submenu 4 Press one of the three available soft buttons to save the instrument settings A highlighted message SETUP N has been saved will appear on screen when the operation is complete 5 Press CLEAR MENU to resume normal instrument operation Restoring a Setup To recall a setup or restore factory default settings 1 Enter the top menu 2 Use the multi function knob to scroll the menu highlight to Restore Setups Press any soft button to enter the submenu It will resemble the display illustrated in Figure 31 3 Press one of the four soft buttons to recall restore the associated instrument settings A highlighted message SETUP N has 764 Digital Audio Monitor User Manual Operating Basics been restored will appear on screen to signal that the operation is complete 4 Press CLEAR MENU to resume normal instrument operation with the newly recalled settings Restore Setups Selection SETUP 1 SETUP 1 SETUP 2 SETUP 3 FACTORY SETUP TOP MENU CLEAR Press MENU button for help SSE CEEE a J Figure 31 The Restore Setups submenu Editing a Setup To edit an existing saved setup 1 Recall the Setup through the Recall Setups submenu 2 Change the instrument settings as desired 3 Save the Setup as the same setup number through the Save Setups submenu 764 Digital Audio Monitor User Manual 41 Operat
37. ay vary Printing You can use the hardware and software settings described below to print a session report m Printer port QMS PS 410 serial DB25 764 Digital Audio Monitor User Manual Reference m Printer Communications Settings ESP automatic protocol sensing 9600 baud 8 bits 1 stop bit DTR DSR flow control m 764 Serial Port settings Flow Control HARDWARE Baud Rate 9600 Communicating with a PC You can use the software and settings below to establish communications with a personal computer m PC Software Microsoft Windows 95 Hyperterminal Accessory application Many other communications or terminal applications also work m Hyperterminal application File menu Properties command Connect To tab settings Connect Using COMx depends on computer configuration often COM2 when a serial mouse is installed Configure Baud Rate 19200 or 38400 Bits 8 Stop Bits 1 Parity none Flow Control Xon Xoff m 764 Serial Port settings Flow Control SOFTWARE Baud Rate 19200 or 38400 Be sure to set compatible baud rates before attempting to establish communications At power on of the 764 a command prompt 764 gt and product identification message will be displayed on the PC or terminal screen when connected 764 Digital Audio Monitor User Manual 65 Reference 66 Outputting a Session Report You can test your RS 232 connection by outputting a short session r
38. bmenus are summarized below See the Getting Started section of this manual starting on page 1 for an explanation of general menu techniques The Level Meters Submenu Use this Submenu to configure the appearance and behavior of the Audio View level meters 764 Digital Audio Monitor User Manual Reference Table 2 Level Meters submenu Item Display Mode Interpolation Ballistics Peak Hold Time Peak Program Level dBFS Test Level dBFS Set 0 dB Mark to Consecutive FS Sam ples for CLIP Consecutive 0 Sam ples for MUTE CLIP MUTE Hold Time Sec Ignore Validity Bit Suppress Sync Loss Flags Choices 4 Channels Ch 1 2 and Sum amp Diff Factory setting 4 Channels Ch 3 4 and Sum amp Diff OFF ON ON PPM True Peak True Peak Extended VU 0 to 10 seconds 2 0 to 30 dBFS 8 dBFS cannot be set below Test level 0 to 30 dBFS cannot be set above Peak Program level DIGITAL FULL SCALE PEAK PROGRAM 18 dBFS DIGITAL FULL SCALE TEST LEVEL 1 to 100 1 0 to 100 10 aa NO YES NO NO NO YES Display Mode Use the Display Mode setting to configure the audio view to contain four level meters as shown in Figures 15 and 17 on pages 19 and 23 respectively or two level meters plus Sum and Difference bars When Sum and Difference bars are selected the two left hand bars show the levels of one input pair either channels 1 2 764 Digital Audio Monitor
39. cay character istics of the meters The meters can emulate the dynamic re sponse of three common types of analog audio level meter Choices are VU with the scale extended to permit display of true peaks on the same bar PPM a quasi peak meter with 10 ms in tegration time and slow decay and True Peak with instantaneous response and slow decay 2 Scale Units BFS or dBr By default the zero dB mark is at digital full scale and units are in dB relative to full scale ABFS You may also set the 0 dB mark to either the Peak Program level or the Test level see items 3 and 4 below In either case the scale units are dB relative to the specified zero point dBr 764 Digital Audio Monitor User Manual 19 Operating Basics 20 dBFS dBFS 0 0 Dansi i ie i 10 10 _ ae _ 20 Or 20 30 30 40 40 50 50 70 70 1 2 Sum Diff D T a 3 4 Sum Diff Figure 16 The sum and difference display modes 3 4 5 Peak Program level The Peak Program level is usually the maxi mum permissible level for audio program material The default Peak Program level is 8 dBFS you may set it to the integer val ue between 0 FS and 30 dBFS that is appropriate to your par ticular needs The diamond shaped Peak Program level scale markers will be red on an optional external color display if the audio program exceeds this level the
40. ch the Tektronix service center is located Customer shall be responsible for paying all shipping charges duties taxes and any other charges for products returned to any other locations This warranty shall not apply to any defect failure or damage caused by improper use or improper or inadequate maintenance and care Tektronix shall not be obligated to furnish service under this warran ty a to repair damage resulting from attempts by personnel other than Tektronix representatives to install repair or service the prod uct b to repair damage resulting from improper use or connection to incompatible equipment c to repair any damage or malfunction caused by the use of non Tektronix supplies or d to service a prod uct that has been modified or integrated with other products when the effect of such modification or integration increases the time or difficulty of servicing the product This warranty is given by Tektronix with respect to this product in lieu of any other warranties expressed or implied Tektronix and its vendors disclaim any implied warranties of merchantabil ity or fitness for a particular purpose Tektronix responsibility to repair or replace defective products is the sole and exclusive rem edy provided to the customer for breach of this warranty Tektro nix and its vendors will not be liable for any indirect special incidental or consequential damages irrespective of whether Tektronix or the vendor has advance no
41. configuration jumper locations 95 Table 33 Power cord identification 0 666 cc eens 99 764 Digital Audio Monitor User Manual V Table of Contents vi 764 Digital Audio Monitor User Manual General Safety Summary Review the following safety precautions to avoid injury and prevent damage to this product or any products connected to it To avoid potential hazards use this product only as specified Only qualified personnel should perform service procedures To Avoid Fire or Personal Injury Use Proper Power Cord Use only the power cord set provided with this product or some other properly rated and approved cord set configured for the local mains supply outlets Use Proper Power Source This product is designed to operate from a power source that will apply no more than 250 Vrms between the supply conductors or between either supply conductor and ground Ground the Product Before connecting the product s input or output terminals plug the power cord into a properly wired receptacle A protective ground connection through the grounding conductor in the power cord is essential for safe operation Use Proper Fuse Use only the fuse type and rating specified for this product Operate Only Within a Suitable Enclosure Operate this product only within an enclosure that prevents contact with interior electrical components Provide Proper Ventilation Refer to the manual s installation instructions fo
42. d Configuring the Level Meters 5 4 cas ciotaaeaaeews dey Sum and Difference Bars 6acs eon e vee eG koe ea The Phase Display 3 24 i404 6s4bbevaddaadaedawodaeerness The Lissajous Pattern os5sc50 vgi0es e ees ban eae oe The Correlation Meter ya0us4a eesyabede te uuse vs 764 Digital Audio Monitor User Manual Table of Contents Features of the Session Display 29 Session Statistics 4 o lt c5nnadey d Goad heeeeeanwhewe ee 30 Session Reports os 65440 be eae RARE RH ERNE RSG RAKES 34 The Channel Status View bsax4sayc449 eieep eas nesia s 37 The User Data View sn 40 06550 8054 4a e50h esses wees 39 Saving and Restoring Setups sa 4 ss 4 lt d vcee neta dav ead 40 Saving a SeUlp s odpro eaa a a a 40 Restoring a Setup s s 40c0dsedeetsas hue ey oud eed aads 40 Editing a Setup a5 y45eS MV EN HSS ESS Sey Soe eKN a HSS 41 Refere ce 26 cud isan eaase seesaw enw isun ease eed 43 evel Meters 24yc6ne eet eadsedasehegaowee eee a E a 43 Meter Ballistics and Alignment Levels 43 In Bar Warning Messages 6c 4ce scs ede wns evans 44 Correlation Meter Algorithm 0 00005 46 Selecting Headphone Channels 2005 48 PUMIMEMUS ayes45Sd ord eee onvak hs seus Geet eade 48 The Level Meters Submenu 224 4 542d9 esa aaraes 48 The De emphasis Submenu 2004 53 The Phase Display Submenu 4 54 Headphones Submenu lt ss404645acs ance caeev sa
43. d enh 56 Input SUDMENU acs2arscsoRshekeoaGeeeoeksane des 56 Time Code Submenu 4 4 es esiasiwcdease eo R bese anes 57 Serial Port Submenu s6 kd 45445666450 Sa nnne 58 Save Setups Submenu 25 64 4 uneSdedde edna eidhavauy 59 Restore Setups Submenu faved eae ceevews ruren 60 Screen Saver Submenu 2 54 cavexen sheeked ene pase ox 60 Service Submenu essesererereeserere baw ew ea 61 Using the RS 232 Port gxs8 acnaton do okora Ree tones 62 Cable Requirements 2 42sceee eeddepsvereuaiws ss 62 Communication Examples 0000 eee 64 Outputting a Session Report 000 000 66 Remote Control Commands 2 wessacsesdy eee edenan 66 Appendix A Specifications 0 cc eee w cece eens 75 Appendix B Error Warning Messages 0006 83 Appendix C Options sssssssssssesosssesososeso 89 Embedded Audio Input Option 01 89 ii 764 Digital Audio Monitor User Manual Contents Operating Information 64 0 06 4 ke ana eae oaeak eee 90 Changes to the Session Statistics Display 92 Additional Error Warning Messages 92 Analog Line Output Option 02 0 0005 93 Configuring the Output 0 0 eee eee 95 Connecting the Instrument 4 40 setae awa eee ea a 97 Power C fdS 6355545055 KGRS SN aRRSSD AUR OR ERRRS ASE 99 Glossary avenues cndevinwindwaseudewds wine eeawedaed 101 INGOX EEE need E E E E E E E E hase ges 103 List of Fi
44. d return to the most recent view Audio Channel Status or User Data 9 Headphone VOLUME control The VOLUME knob controls the ana log headphone output gain on instruments equipped with Option 02 it also controls the gain of the rear panel analog audio out puts 10 Display BRIGHTNESS control Turn the BRIGHTNESS knob to ad just the brightness of the 764 display Does not affect the output of the rear panel VGA VIDEO connector The Level Meters The 764 level meters are vertical bar graphs in which the height of each bar indicates the amplitude of the audio program contained on the corresponding input channel The levels of all four input channels are shown in the default meter configuration illustrated in Figure 15 You can also select through on screen menus two channel plus sum and difference mode shown in Figure 16 Indeed almost every feature of the 764 level meters may be customized to suite your particular needs The features and your options are explained briefly in the following numbered paragraphs Choose the options that are appropriate to your particular application through the on screen menus refer to Configuring the Level Meters beginning on page 22 for more information 764 Digital Audio Monitor User Manual Operating Basics Gers O doul a 1 Coe eS G ji macs Figure 15 The 764 Level Meters 1 Meter Ballistics i e dynamic response or attack de
45. default channels 1 and 2 are phase pair A and channels 3 and 4 are pair B You can however designate channels 1 and 3 or 1 and 4 or channels 2 and 3 or 2 and 4 as either pair A or pair B Change the channels of the phase pairs using the following steps 1 Press the MENU button 2 Turn the multifunction knob until PHASE DISPLAY is highlighted 3 Push any of the inner group white soft key buttons to the right of the display screen to bring up the Phase Display screen 4 Rotate the multifunction knob to highlight Pair A left or right or Pair B left or right 5 Push the appropriate white soft key buttons to set any channel 1 through 4 to left and right of either Pair A or Pair B 6 Push CLEAR MENU button to return to the screen that was displayed before you pushed the MENU button Note that if you pair channels from different inputs the two data streams must be synchronized If data slippage is 1 2 frame or greater the 764 will not be able to unambiguously identify left right sample pairs and the phase display will not be reliable If that happens a warning message appears on the display 764 Digital Audio Monitor User Manual 55 Reference 56 Headphones Submenu Use the Headphonse submenu Table 5 to determine the input channels to be decoded and output through the headphone jack Table 5 Headphones submenu Item Factory setting Audio Source AUTO follows phase AUTO follows phase MANUAL Manu
46. ds important utility to the 764 because it permits screening of digital audio programs for errors and peak levels 764 Digital Audio Monitor User Manual Operating Basics without requiring constant operator attention When errors and peaks are encountered they are time stamped with the active session time code which makes it easy to return to the part of the program that contains the event of interest See page 34 for more information True Peak Session 00 00 00 00 Run Stop in phase Figure 13 The 764 AUDIO PHASE view Monitoring the Ancillary Data You can monitor ancillary data contained in the digital audio signal through two additional 764 view options Channel Status View The Channel Status view reports the information embedded in the channel status bytes of the incoming serial digital signal Select the Channel Status view by pressing CLEAR MENU if necessary to exit the on screen menus then the VIEW CH STATUS button You may select a number of Channel Status view options with the Soft buttons to the right of the display Refer to The Channel Status View beginning on page 37 for more information User Data View The User Data view reports the information embedded in the User bytes of the incoming signal Select the User data view by pressing CLEAR MENU if necessary to exit the on screen 764 Digital Audio Monitor User Manual 15 Operating Basics menus then the VIEW USER DATA button You may sel
47. e is displayed at the bottom of the Audio view if Video Input is selected but there is no video signal present The in bar INPUT UNLOCKED flag also appears in all four meter bars whenever the No Video Input message is displayed 764 Digital Audio Monitor User Manual Appendix C Options NOT PRESENT The in bar NOT PRESENT flag indicates that although video input is detected there is no active audio on the corresponding channel no channel ID is detected Analog Line Output Option 02 Option 02 replaces the balanced XLR digital audio outputs with analog audio line outputs it is available only as a factory option to the 764 and cannot be installed in existing instruments Option 02 has the following features and characteristics m The option provides two channels typically left and right of balanced analog output m The audio channels present on the left and right analog line outputs are those selected by the user for headphone monitoring i TERM DIGITAL IN nea Ee na eT DIGITAL DIGITAL LOOP THROUGH LOOP THROUGH Figure 38 Option 02 connectors m The analog output can be configured one of three ways fixed at 24 dBm into a balanced 600 ohm load variable up to 24 dBm also for a balanced 600 ohm load or variable up to 2 0 Vrms into an unbalanced 10 kQ or greater load When the instrument is set for variable output the front panel VOLUME knob controls output gain 764 Digital Audio Monitor User Manual 9
48. ect a number of User Data view options with the Soft buttons Refer to The User Data View beginning on page 39 for more information Other Features With the 764 you can also save up to three instrument configurations setups for later recall Refer to page 40 Front panel Controls Figure 14 shows the 764 front panel controls 1 2 3 POWER switch Press the POWER switch to toggle between ON and STANDBY A portion of the instrument power supply re mains active when the switch is in the Standby position Unplug the 764 if it is necessary to isolate it completely from the main power supply instrument settings are preserved with internal bat tery back up VIEW Selection buttons Use the VIEW buttons to select among the AUDIO CH annel STATUS and USER DATA views These buttons are inactive when a menu is present on the 764 display The OTHER button is not used in this version of the instrument PHASE DISPLAY and SESSION buttons Use the PHASE DISPLAY buttons to configure the right portion of the Audio view The A and B PHASE DISPLAY buttons select a Lissajous Phase display with correlation meter as illustrated in Figure 13 The A and B phase pairings are by default m Pair A left input channel 1 Pair A right input channel 2 m Pair B left input channel 3 Pair B right input channel 4 You can change the orientation of the Lissajous display from soundstage to X Y and the phase channel pairings thro
49. ems are identical except for the affected channel Table 3 De emphasis submenu Item Factory setting Channel NONE NONE Where 1 2 3 or 4 AUTO CCITT J 17 50 15 Selecting either CCITT J 17 or 50 15 will force that type of de emphasis When AUTO is selected the 764 will apply the appropriate de emphasis if either CCITT J 17 or 50 15 emphasis is indicated in the channel status data of the digital input signal If you choose de emphasis please be aware that although the 764 will continue to use raw input data when reporting MUTEs and CLIPs the level meters and session statistics will measure and report levels in the de emphasized signal Because de emphasis attenuates the higher frequencies of a signal selecting de emphasis may result in meter readings and true peak statistics that understate the actual signal levels When any type of de emphasis has been selected it is indicated by a flag on the display above the meter pair as shown in Figure 34 In the configuration pictured de emphasis has been selected for input channels 1 2 and 3 but not for channel 4 If de emphasis was also not selected for channel 3 the De emp flag would not appear above the right hand meter pair 764 Digital Audio Monitor User Manual 53 Reference 54 True Peak Session time Figure 34 The De emphasis flags The Phase Display Submenu Use the Phase Displaly submenu Table 4 to configure the appe
50. ennnannenenannm tereeeanenetonnnenenentenenannnantennnnennnet Highest Bar Reading 0 7 0 0 0 dBFS A a 9 aa a i a en a a Sn Sa a a aa a ak Sa i a a ea ai aa a aa aE Clips Found 0 0 234 234 a Sa a le Sa a a ras SE a Se a a Sm a a ea eA a a er Mutes Found 15 17 0 0 lela alata tat alalaiel alalatatetatalaialatal stale t Tetelnlatatalotel etal talelatatelatatatetal telelalatelatelatatel taleletetetalelatatel 2 Invalid Samples Found 0 0 0 0 eecrecenenenennnennnnnnann m tereeeanenetanenenenantenenananantennnneannnet Parity Errors Found 0 0 0 0 crceeemenennennnnnnnennnnn Sl a aN lla ela aad al ad aaa a Code Violations Found 11 12 27 33 Sees nor ose cess ses cess Poss ses ose bee eee see poss ccs scope se ose soap Number of Active Bits 24 24 24 24 eenacenannnennnnnnenenannm Totelntelotelatelatel tale lalatelatetatatel taletaletelateletalel talelatetatetetateiel 2 DC Offset 58 9 70 3 52 2 62 0 dBFS la Nal a aol oa a totaal teh dental aaa el allel teeta a Starting Sample Rate 44 10 48 00 kHZ Ending Sample Rate 48 00 48 00 kHZ Number of changes 3 3 alata alata tata alate alatalal at ataeietatal stale t Sotelalalataletel etal talelolaieletatalatal telelalatelatelaleiel taleleteletelalatatel 2 Frame Sync Error 3 0 alata atntatatelnlaiel alataleletntaletatatelatata f totelalaletalatelatal talelatateletaiolatal teleleiatelatelatelel tatelatetelelelalateh tatelalatal Figure 26 A short session report 764 Digital Audio Monitor User Manual
51. eport 1 Confirm that the Copy selection of the 764 Serial Port submenu is set to either SHORT REPORT or LONG REPORT Clear the on screen menu and display the Audio Session view Run a session Stop the session but do not reset it eo Se oS Press the on screen Copy soft button feature in Figure 23 on page 29 The 764 will send the report to the printer or PC As it sends the report the monitor indicates the number of remaining lines on the bottom of the display Press the soft button a second time to cancel the report Remote Control Commands Once you have established communications between the 764 and a personal computer or ASCII terminal you may use the remote control commands to operate the audio monitor from the computer or terminal Command Syntax Use the colon as the command argument separator as in the following examples PRESS SKEY4 the command to press soft key number 4 MENU DISMODE 1 the command to display the sum and difference of Channel 1 and Channel 2 You can string the remote commands together on a single command line Use a semicolon to separate commands on the line as in the following example PRESS APH GET CURTP 2 GET SHIGH 2 The commands are not case sensitive although this section shows them in all uppercase for clarity You can also abbreviate the commands Only enough letters to make the command unique need be used in a command as shown in the following example G T G S
52. er messages The MUTE indicator is one of seven messages that can appear in the lower half of each meter bar The remaining messages are intended to alert you to possible errors in the input signal they are explained in In Bar Warning Messages beginning on page 44 You can specify the number of consecutive all zero samples required for a MUTE indication The default is 10 samples the range is 0 to 100 The Mute indicator always reacts to unpro cessed input data regardless of Interpolation or de emphasis settings refer to Interpolation on page 50 or The De emphasis Submenu on page 53 You may also specify the persistence hold time for the in bar indicators between and 30 seconds the default is 2 seconds 7 Meter bar labels The meter bar labels depend on the display mode The channel numbers 1 2 3 and 4 correspond to the rear panel input labels Sum indicates L R 2 and Diff indicates L R 2 8 True peak indicators The true peak indicators always show true peak values regardless of the selected meter ballistics These indicators are particularly useful when you have selected PPM or VU ballistics which have rise times that may prevent you from seeing peaks in program material containing steep transients By default the peak indicators persist at the most recent program peak for 2 seconds you can set this peak hold time through the level meters submenu between 0 and 10 in one second in c
53. ession Display Session Reports The Channel Status View The User Data View and Other Features Please take a few minutes to familiarize yourself with this section and the information contained in it Consult the text whenever you have a question regarding instrument operation Because the Tektronix 764 Digital Audio Monitor is intended as a tool for use in a production environment every effort has been made to keep operation as simple and intuitive as possible An attempt has also been made to keep this section of the manual brief and easy to use You will find detailed information about the more technical aspects of 764 operation in the Reference section of this manual Overview The 764 permits in line monitoring of the audio program contained in a digital audio signal without first converting it to analog form In addition it can report and interpret the ancillary data that is transmitted through the Channel Status and User Data bits of the digital data stream The 764 uses three display views to perform those functions the Audio view the Channel Status view and the User Data view as described in the following paragraphs To locate buttons mentioned in the text refer to Front Panel Controls beginning on page 16 Monitoring an Audio Program with the Audio View The Audio view with the Session Statistics displayed as shown in Figure 12 is the power up default configuration of the 764 Otherwise the Audio View is never mo
54. et the serial communication parameters of the connected device to 8 bits 1 stop bit and no parity Be sure that the same Baud rate is selected at the 764 and the connected device Male DBS Connect to 764 DB25 female shown Connect to DTE device Figure 35 Connecting to a DTE device with a DB25 serial port 764 Digital Audio Monitor User Manual 63 Reference 64 eO N 7 DB25 male shown Connect to DCE device Male DB9 Connect to 764 13 Figure 36 Connecting to a DCE device with a DB25 serial port NOTE Most Personal Computers are DTE devices however printers may be either DTE or DCE and the type may not be obvious from the printer documentation or the gender of the RS 232 connector If you have trouble outputting a 764 Session report first verify that communication parameter and Baud rate settings are correct then try reversing the conductors at pins 2 and 3 and 7and amp at the cable end that is connected to the 764 Communication Examples The following hardware software and 764 settings have been verified effective for either printing a session report to a printer or download ing the report to a PC running Microsoft Windows 3 1 You may find the examples helpful please note however that mention of third party software or equipment does not constitute endorsement or recommendation by Tektronix Inc The settings required for your particular printer PC and communications software m
55. evel includes appliances portable tools and similar products Equipment is usually cord connected CAT Secondary signal level or battery operated circuits of electronic equipment 764 Digital Audio Monitor User Manual 81 Appendix A Specifications 82 764 Digital Audio Monitor User Manual Appendix B Error Warning Messages This appendix lists and explains the various error and warning messages that can appear on the 764 display Figure 32 on page 45 shows the In bar message location Channels not synchronized Location Audio View phase display The left and right samples are not synchronized well enough to be reliably paired Only possible when left and right channels are chosen from different inputs for example channel paired with channel 4 CLIP Location Audio View above the meter bar of the affected channel The CLIP indicator flashes when the digital audio data on the input channel remains at full scale for n or more consecutive samples The factory default value of n is one 1 it may be changed through the Level Meters submenu Full scale means maximum coding level either positive or negative Maximum coding level is determined by the number of active bits detected in the digital input signal This indicator persists for the CLIP MUTE Hold Time also set through the Level Meters submenu When a Session is running the instrument counts CLIPs and displays the current total on the Session displa
56. fields will read off when the Ignore Validity Bit item in the Level Meters submenu is set to YES Number of parity errors detected during the session This will increment if the 764 detects incorrect parity in a received digital audio word Parity errors suggest problems with the digital signal source or signal path m Code Violations the number of raw serial data subframes containing biphase coding errors that are encountered during the session Code Violations indicate an incorrect or unreliable serial digital signal or transmission path m The digital audio word length detected by monitoring bit activity in the part of the digital signal reserved for audio sample data Although it is not likely this number can differ from the sample length information indicated in the Channel Status bits of the digital input signal m DC Offset reported in dBFS dB relative the the full scale amplitude of the input signal Note that an offset of 60 dBFS is only 0 001 of the full scale amplitude while an offset of 90 dBFS is approximately 3 16 x 107 of full scale m The measured sample rate This number is independent of the sample rate indicated in the Channel Status bits of the digital input data but should be the same Non standard sample rates can cause constantly changing frame synchronization errors and 764 Digital Audio Monitor User Manual 31 Operating Basics 32 SYNC ERR flags as shown in Figure 24 Ple
57. gh the Level Meters submenu A setting of zero 0 disables this indicator The MUTE indicator persists for the CLIP MUTE Hold Time set through the Level Meters submenu When a Session is running the instrument counts MUTEs and displays the current total on the Session display No Reference Signal Location Audio View below the Session or Phase display The 764 is not locked to an incoming signal on the REFERENCE input Likely causes of this message include missing reference signal incorrect Reference Input setting in the Inputs submenu or an inadequate or defective DAR signal The flag will persist until a valid reference signal is detected or until Suppress Sync Loss Flags is selected through the Level Meters submenu No Video Input Option 01 only Location Audio View below the Session or Phase display Video input is selected but there is no video signal present at the input The in bar INPUT UNLOCKED flag also appears in all four level meter bars whenever this message is displayed The flag persists until a valid digital video signal is detected at the SER VIDEO IN connector or until another input is selected 764 Digital Audio Monitor User Manual Appendix B Error Warning Messages NOT PRESENT Option 01 only Location In bar The NOT PRESENT flag indicates that although video input is detected there is no active audio on the corresponding channel no channel ID is detected PARITY
58. gures Figure 1 The Tektronix 764 Digital Audio Monitor x1 Figure 2 Rear view of the 764 in a Tektronix enclosure 2 Figure 3 The 764 rear panel and connectors 3 Figure 4 Connecting the standard 764 to your system 4 Figure 5 Using an external color monitor 6 Figure 6 Outputting a session report 00 5 7 Figure 7 The headphone output schematic 8 Figure 8 Controls for initial power up and configuration 9 Figure 9 The top menu HELP message 10 Figure 10 Selecting from the top menu 11 Figure 11 The inputs subment 5 2scc08 vse eaas au snn ds 12 Figure 12 The 764 AUDIO SESSION view 14 Figure 13 The 764 AUDIO PHASE view 15 Figure 14 764 front panel controls 04 17 Figure 15 The 764 Level Meters 5 423 4saieenasaes aks 19 Figure 16 The sum and difference display modes 20 Figure 17 Creating a custom meter scale 23 Figure 18 The Level Meters submenu 24 Figure 19 Soft buttons and numeric settings 24 Figure 20 Sum and difference bars and the session display 26 764 Digital Audio Monitor User Manual iii Table of Contents Figure 21 Figure 22 Figure 23 Figure 24 Figure 25 Figure 26 Figure 27 Figure 28 Figure 29 Figure 30 Figure 31 Figure 32 Figure 33 Figure 34 Figure 35 serial por
59. hannels 1 through 4 1 through 4 5 through 8 9 through 12 13 through 16 Time Code Submenu Select the time code to be displayed on the Session Display and used to time stamp errors on Session reports Table 9 Time Code submenu Item Factory setting Time code in use SESSION SESSION VITC LTC 764 Digital Audio Monitor User Manual 57 Reference 58 Serial Port Submenu The Serial Port submenu contains items used for setting the serial port parameters and controlling the content of the session report The items and choices are listed in Table 10 and explained in the subsequent paragraphs Table 10 Serial Port submenu items Item Factory setting Flow Control SOFTWARE HARD SOFTWARE WARE BOTH NONE Baud Rate 38400 19200 9600 38400 2400 Copy NO REPORT SHORT NO REPORT REPORT LONG RE PORT Peak Reading Interval 0 1 2 300 seconds 60 sec Flow Control Scroll to the Flow Control menu choice by turning the multi function know and then press the soft button that corresponds to the appropriate type of flow control If you do not know which flow control is correct for your application first try HARDWARE when outputting a report to a printer and SOFTWARE when downloading a report to a personal computer Baud Rate Scroll to the Baud Rate menu choice and press the soft button that corresponds to rate that is used by the receiving printer or PC For fastest data transfer when
60. hase Display Pair A Left Channel Assignment Phase Display Pair A Right Channel Assignment Phase Display Pair B Left Channel Assignment 764 Digital Audio Monitor User Manual Reference Table 19 Remote control MENU commands Cont Command MENU PBRIGHT lt 0 3 gt MENU AUDSRC lt 0 1 gt MENU MLEFT lt 0 3 gt MENU MRIGHT lt 0 3 gt MENU SOURCE lt 0 1 gt Option 01 only MENU CH1 2IN lt 0 1 gt MENU CH3 4IN lt 0 1 gt MENU REFINP lt 0 1 gt MENU SD_GROUP lt 0 3 gt Option 01 only MENU TIME lt 0 2 gt MENU FLOW lt 0 3 gt Value setting Submenu item O channel 1 Phase Display Pair B Right l channel 2 Channel Assignment 2 channel 3 3 channel 4 0 Manual Headphones Audio Source 1 Auto follows phase also applies to Option 02 O channel 1 Headphones l channel 2 Manual Left Channel 2 channel 3 also applies to Option 02 3 channel 4 O channel 1 Headphones l channel 2 Manual Right Channel 2 channel 3 also applies to Option 02 3 channel 4 0 Digital Audio Inputs Input Audio source 1 Digital Video Input 0 XLR balanced Input CH 1 2 Input 1 BNC unbalanced 0 XLR balanced Input CH 3 4 Input 1 BNC unbalanced 0 XLR balanced Input Reference Input 1 BNC unbalanced 0 1 through 4 Input Channels 1 5 through 8 2 9 through 12 3 13 through 16 O SESSION Time Code in use 1 VITC 2 LTC 0 S oftware Serial Port Flow Control 1 Hard
61. he few differences from standard operation as discussed in the rest of this manual Connect the Instrument Connect the 764 to the digital video signal path with appropriate 75 Q coaxial cable such as Belden 8281 Notice that the SER VIDEO IN and SER VIDEO OUT connectors make up an active loop through in which the output is an equalized and regenerated copy of the input A termination is not required on the serial video output when the instrument is installed at the end of the signal path Select the Digital Video Input and Audio Channel Group Configure the 764 to monitor the serial video input with the following steps 1 Switch instrument power on 2 Press the MENU button to enter the on screen menu hierarchy 3 Turn the multi function knob to highlight the Input menu selection then press the SUBMENU soft button or any white button to enter the Input submenu 4 Press the soft button that corresponds to the Digital Video Input choice Notice that the Input submenu changes to include only Audio Source and Channels selections 764 Digital Audio Monitor User Manual Appendix C Options 5 Turn the multi function knob to highlight the Channels menu item then press the soft button that corresponds to the channel group channels 1 4 5 8 9 12 or 13 16 that you want to monitor If you do not know which audio channels are active on the input video ignore the channel setting and proceed to the next step 6 Press the
62. hms TTL compatible TTL compatible 25 175 MHz 31 469 kHz 59 940 Hz Red Green Blue NC Ground Red Ground Green Ground Blue Ground NC Ground NC NC Horizontal Sync Vertical Sync NC Table 26 Physical characteristics Characteristic Height Width 78 Information 51 inches 13 3 cm 81 inches 21 6 cm 764 Digital Audio Monitor User Manual Appendix A Specifications Table 26 Physical characteristics Cont Characteristic Information Depth 17 inches 43 2 cm Weight Net 10 Ibs 4 54 kg Shipping 17 Ibs 5 oz 7 85 kg Table 27 Power requirements Characteristic Information Input voltage 90 250 VAC Input frequency 50 or 60 Hz Current rating 1 5 A Maximum Power consumption 56 Watts typical Table 28 Environmental characteristics Characteristic Information Temperature NOTE Safety certification compliance to 40 C Operating 0 C to 50 C 32 to 122 F Storage 55 C to 75 C 67 to 167 F Humidity Will operate at 93 relative humidity for up to five days Meets requirements of the five day humidity cycling test described in Tektronix standard 062 2847 00 Altitude NOTE Safety certification compliance to 2000 m Operating to 15 000 feet 4572 m Storage to 50 000 feet 15420 m Vibration Operating 15 minutes each axis at 0 013 inch frequency varied from 7 to 55 to 7 Hz in five minute cycles with the instrument attached to a vibration platform Dwell for 10
63. igital Audio Monitor User Manual Preface The Tektronix 764 Digital Audio Monitor shown in Figure 1 is a tool for monitoring the signal levels and stereo phase of digitally encoded AES EBU and IEC 958 consumer use audio in a production environment The instrument can simultaneously display the levels of two two channel inputs and the stereo phase relationship of any two of the four input channels It can also display numerical data about the audio program material as well as Channel Status and User Data information encoded in the digital audio signal Tektronix 764 Digital Audio Monitor Session 00 00 00 00 Run Stop METER SCALE NORMAL CUSTOM retin EXPAND OFFSET Phase display A accion Fed VOLUME POWER ON a STANDBY E Figure 1 The Tektronix 764 Digital Audio Monitor Through on screen menus and front panel controls the user may configure the response dynamics ballistics reference levels offset and scale of the meters to suit the monitoring needs of the particular installation or situation The user may also choose among several types of stereo phase display This Manual This User Manual is divided into the following sections m Getting Started All the information you ll need to put your new instrument in service Begins on page 13 764 Digital Audio Monitor User Manual xi Preface Operating Basics What you ll need to know f
64. ignal and program either to an ASCII printer or a personal computer see Figure 6 running a communications application such as PROCOMM or the Terminal accessory of Microsoft Windows Refer to Session Reports beginning on page 34 Operate the instrument serial number BO20000 and later by remote control Refer to Remote Control Commands beginning on page 66 for more information Download future 764 software upgrades through a personal computer Please contact your Tektronix representative or the nearest Tektronix office for information about software upgrades Installation instructions are provided with each upgrade kit 764 Digital Audio Monitor User Manual Getting Started Via RS 232 Print or Store Tektronix 764 Monitor Printer Computer Figure 6 Outputting a session report 6 Optional Serial Video Loop Through Instruments equipped with Option 01 Embedded Audio Input have two additional 75 Q BNC connectors SER VIDEO IN and SER VIDEO OUT These connectors make up a loop through that accepts digital video with embedded digital audio Refer to Appendix C Options beginning on page 89 for more information about Option 01 Headphones The front panel headphone output lets you listen to the audio programs contained in the digital input signals The connector accepts a standard 4 inch 6 35 mm stereo plug and is wired as shown i
65. imum Bits Maximum Bits Maximum Bits Maximum Bits 00 00 00 24 00 00 00 24 00 00 00 24 00 00 00 24 Dc Offset Channel 1 Channel 2 Channel 3 Channel 4 Minimum dBFS Minimum dBFS Minimum dBFS Minimum dBFS 00 00 00 nil 00 00 00 nil 00 00 00 nil 00 00 00 nil Maximum dBFS Maximum dBFS Maximum dBFS Maximum dBFS 00 00 00 nil 00 00 00 nil 00 00 00 nil 00 00 00 nil Average dBFS Average dBFS Average dBFS Average dBFS nil nil nil nil Sample Rate Channels 1 2 Channels 3 4 Session kHZ Session kHz 00 00 12 48 00 00 00 26 00 00 Figure 27 Additional data on the long report 764 Digital Audio Monitor User Manual 35 Operating Basics There are two types of time stamped information peak readings and error events Peak readings are the highest true peak and the highest meter reading encountered during each consecutive peak reading interval in the session An error event is a clip mute invalid sample parity error or code violation episode consisting of at least one such error The time stamp is the hour minute second frame when the peak or error occurred in the time format Session VITC or LTC se lected through the Time Code submenu Use the following procedure to output a session report 1 36 Connect the 764 to the printer or PC Cable requirements are explained under Using the RS 232 Port beginning on page 62 Select the appropriate communications and report options flow control baud rate type of report and peak
66. ing Basics 42 764 Digital Audio Monitor User Manual Reference This section contains detailed information about the more technical aspects of 764 operation The subsections are Level Meters Correlation Meter Algorithm Selecting Headphone Channels Submenus and Using the RS 232 Port Level Meters Also refer to The Level Meters Submenu beginning on page 48 Meter Ballistics and Alignment Levels The many level meter options in the 764 may leave the user wondering which settings to use for a given installation or applica tion The short answer is to choose settings to emulate the meters that you are accustomed to However you may not find the translation between the analog and digital worlds completely straightforward Or you may wish to modify your practice and adopt certain standards to ease inter platform and international program exchange In either case the next few paragraphs may help you decide on the Ballistics Peak Program Level Test Level and 0 dB Mark settings for your 764 To ease signal exchange between equipment EBU Recommendation R68 1992 suggests that the alignment level be set at 18 dB below maximum digital coding level that is 18 dBFS This level corresponds to the CCIR 645 renamed ITU R BS 645 2 analog alignment level and allows adequate headroom above the permitted maximum level for PPM metering and meter reading errors The permitted maximum level as defined in CCIR 645 is 9 dB or
67. ion and operating environment See the following paragraphs for explanations of the connectors and their functions 2 764 Digital Audio Monitor User Manual Getting Started T64 DIGNKL AUDIO MONITOR Figure 3 The 764 rear panel and connectors 1 Digital Audio Inputs and Loop Throughs The 764 has two two channel digital audio inputs one labeled CH 1 2 and the other labeled CH 3 4 Each input in the standard instrument has two passive loop throughs that allow you to switch the instrument off with no effect on the through signal m Balanced XLR connectors for signals conforming to the AES EBU AES3 1992 standard Set the TERM switches immediately below these connectors to EXT when the 764 is installed in line select 110 Q internal termination when the instrument is at the end of the signal path 764 Digital Audio Monitor User Manual 3 Getting Started NOTE The male XLR connectors of instruments equipped with Option 02 Analog Line Output are labeled ANALOG OUT these instruments do not have provision for loop through on the balanced XLR connectors The balanced XLR inputs of Option 02 instruments are unterminated when the associated TERM switches are set to EXT To avoid signal degradation always leave the TERM switches of Option 02 instru ments set to 110 Q Refer to Appendix C Options for more information about Option 02 m 75 Q BNC connectors that accept unbalanced digital audio signals in bo
68. ital Full scale or to one of the two user adjustable levels When the zero mark is set to either Peak Program or Test level the scale units are dBr relative to the 0 dB level units above the selected 0 dB mark are positive while units below it are negative Consecutive FS Samples for CLIP Select the number of successive full scale samples that constitute a Clip This setting determines when a clip flag see Figure 15 item 9 on page 19 appears above a level meter and it also affects the number of clips detected during a Session and included in a session report refer to The Session Display beginning on page 29 The range for this setting is 1 to 100 the factory default is 1 Consecutive 0 Samples for MUTE Use this item to select the number of successive full scale samples that constitute a Mute This setting determines when a MUTE indicator see Figure 15 item 6 on 764 Digital Audio Monitor User Manual 51 Reference 52 page 19 appears in a level meter and it also affects the number of clips detected during a Session and included in a session report refer to The Session Display beginning on page 29 The range for this setting is 0 to 100 a setting of O turns mute detection Off in which case no mutes will be reported on the session display or in a session report The factory default is 10 CLIP MUTE Hold Time sec CLIP MUTE hold time is the number of seconds that the Clip indicator and various In bar w
69. l Meters Set0 dB Mark to 1 Peak Program dBr 2 Test Level dBr MENU CLIP lt 1 100 gt 1 to 100 samples Level Meters Consecutive FS Samples for CLIP MENU MUTE lt 0 100 gt 0 to 100 samples Level Meters Consecutive 0 Samples for MUTE MENU CMTIME lt 1 30 gt 1 to 30 seconds Level Meters CLIP MUTE Hold Time sec MENU IGVBIT lt 0 1 gt O NO Level Meters Ignore Validity Bit 1 YES 764 Digital Audio Monitor User Manual 71 Reference Table 19 Remote control MENU commands Cont Command MENU SYNCF lt 0 1 gt MENU DEEMP1 lt 0 3 gt MENU DEEMP2 lt 0 3 gt MENU DEEMP3 lt 0 3 gt MENU DEEMP4 lt 0 3 gt MENU PDISP lt 0 1 gt MENU CORR lt 1 20 gt MENU PALEFT lt 0 3 gt MENU PARIGHT lt 0 3 gt MENU PBLEFT lt 0 3 gt 72 Value setting 0 NO 1 YES 0 None 1 Auto 2 CCITT J 17 3 50 15 0 None 1 Auto 2 CCITT J 17 3 50 15 0 None 1 Auto 2 CCITT J 17 3 50 15 0 None 1 Auto 2 CCITT J 17 3 50 15 0 Lissajous Soundstage Submenu item Level Meters Suppress Sync Loss Flags De emphasis Channel 1 De emphasis Channel 2 De emphasis Channel 3 De emphasis Channel 4 Phase Display Format 1 Lissajous XY 1 to 20 see page 46 Correlation Meter Speed O channel 1 l channel 2 2 channel 3 3 channel 4 O channel 1 1 channel 2 2 channel 3 3 channel 4 O channel 1 l channel 2 2 channel 3 3 channel 4 Phase Display P
70. l data on the horizontal axis emulating the conventional X Y display of an oscilloscope The default Soundstage orientation shown on the left in Figure 21 rotates the X Y pattern 45 degrees counterclockwise so that the channel data are plotted along diagonal axes and mono or in phase audio appears along the vertical straight ahead axis If you are unfamiliar with Lissajous phase patterns and their interpretation see Tektronix application note 21 W 6244 2 Stereo Audio Measurements Using the 760A Audio Monitor The concepts discussed apply to the Lissajous display of the 764 as well The Correlation Meter The Correlation meter illustrated in Figure 22 displays a true mathematical phase correlation mono compatibility between the two channels of the phase pair independent of signal amplitude You may find it easier to interpret the correlation meter than the Lissajous pattern The position of the diamond shaped pointer indicates the correlation between the two selected channels The meter will read 764 Digital Audio Monitor User Manual 27 Operating Basics 1 when the channels contain identical signals frequency and phase it will measure 1 when the signals have the same frequency or frequencies but are 180 degrees out of phase A center scale 0 reading indicates uncorrelated or random signals 1 ma J 1 Figure 22 The phase correlation meter When you monitor audio programs as oppo
71. least confusion expand the scale to the desired range first then adjust the offset to view the meter region of interest For example to change normal scale to a custom scale showing only the 10 to 30 dBFS range see Figure 17 1 Press METER SCALE EXPAND then turn the multi function knob clockwise to expand the scale range to 20 dB top to bottom 2 Press METER SCALE OFFSET and turn the multi function knob counterclockwise to shift the scale upwards by 10 dB 764 Digital Audio Monitor User Manual Operating Basics Press METER SCALE NORMAL to restore the default meter scale to later restore the custom scale and offset press METER SCALE CUSTOM dBFS Normal Scale 1 Expanded to 20 dB 2 Offset by 10 dB Figure 17 Creating a custom meter scale Level Meter Submenu selections All remaining level meter configura tion selections are made through the Level Meter submenu Follow the steps below to make menu selections As with meter scale all selections apply to all four input channels and all four meter bars 1 Press CLEAR MENU if necessary to exit any menu and resume normal operation 2 Press MENU to enter the root menu the TOP MENU 3 Turn the multi function knob to scroll the menu highlight to the Level meters entry 4 Press any soft button to enter the level meters submenu The display will resemble Figure 18 764 Digital Audio Monitor User Manual 23 Operating Basics
72. me code can be shown on the Session display and stamped on each error on a printed Session Report The format of the time display is Hours Minutes Seconds Frames 3 Reference Inputs Connect your house digital audio reference DAR signal to one of the REF IN connectors These connectors one BNC one XLR accept the same formats as the Digital Audio Inputs They are internally terminated As with the audio inputs the default connector is XLR use the on screen menus to select the BNC connector The 764 can use any AES signal as a DAR it will use the reference input to detect and measure frame synchronization of AES signals If you do not connect a house DAR to one of the reference inputs the 764 will monitor synchronization of the CH 3 4 input signal with the CH 1 2 input signal For more information refer to the explanation of the Frame Synchronization Error session statistic on page 32 4 VGA Video Output To see a larger color image of the 764 display as illustrated in Figure 5 connect a VGA compatible monitor to this standard 15 pin output Table 25 on page 77 lists the characteristics of the Video Output signal 764 Digital Audio Monitor User Manual 5 Getting Started VGA or SVGA Monitor From VGA VIDEO Output Figure 5 Using an external color monitor 5 RS 232 Communications Port Through the RS 232 port you can Output a record of the input s
73. minutes each axis at any resonant frequency or 33 Hz if no resonant frequency is found Tektronix std 062 2858 00 Shock non operating c 30 Gs 4 Sine 11 ms duration 3 shocks per surface 764 Digital Audio Monitor User Manual 79 Appendix A Specifications Table 28 Environmental characteristics Cont Characteristic Transportation Equipment Type Equipment Class Installation Category Pollution Degree Emissions Information Meets the requirements of NTSB Test Procedure 1A category ll 24 inch drop Measurement Class I grounded product As defined in IEC 1010 1 Annex H Installation Category II as defined in IEC 1010 1 Annex J Pollution Degree 2 as defined in IEC 1010 1 indoor use only 47 CFR Part 15 Subpart B Class A Table 29 Certifications and compliances EC Declaration of Conformity EMC EMC Compliance FCC Compliance 80 Meets intent of Directive 89 336 EEC for Electromagnetic Compatibility Compliance was demonstrated to the following Specifications as listed in the Official J ournal of the European Communities EN 50081 1 Emissions EN 55022 Class B Radiated and Conducted Emissions EN 50082 1 Immunity IEC 801 2 Electrostatic Discharge Immunity IEC 801 3RF Electromagnetic Field Immunity IEC 801 4E lectrical Fast Transient Burst Immunity Meets the intent of Directive 89 336 EEC for Electromagnetic Compatibility when it is used with the product s stated in the
74. n Figure 7 Adjust the output level with the VOLUME knob 764 Digital Audio Monitor User Manual 7 Getting Started Tip Left 0O Ring Right o Signal Ground Figure 7 The headphone output schematic By factory default the headphone output automatically follows the phase display that is it contains the audio programs decoded from the two channels that you are monitoring with the Lissajous pattern and correlation meter You may also choose to listen to any two of the input channels independent of the phase display choices for instructions refer to Selecting Headphone Channels on page 48 Supplying Power A You can operate the 764 on any AC power supply that provides 90 to 250 V at 50 to 60 Hz If the power cord supplied with your instrument is incorrect for your local AC supply please contact your nearest Tektronix representative or field office WARNING Line voltage will be present in the instrument whenever power is supplied even if the POWER switch is set to STANDBY Always disconnect the power cord before removing the instrument from its cabinet 764 Digital Audio Monitor User Manual Getting Started Initial Power Up and Configuration Once you have connected a signal source to at least one of the 764 DIGITAL AUDIO inputs switch the instrument On When the start up diagnostics are completed the instrument will begin operation in the Audio View Session display If a signal source i
75. nd to transmission order LSB first of the Channel Status bits Use the knob as in the binary display to highlight bits or bit blocks for decoding Press the CHAN soft button repeatedly to cycle among the four input channels m Hex format is included for compatibility with other instrumenta tion All four input channels are shown on one display CHANNEL STATUS Binary Channel 3 10000101 00100000 00001000 00100000 00000100 00000000 00000000 00000000 00000000 00000000 00000000 00000000 01000001 00000000 01001101 00000000 00110111 00000000 00110000 00000000 00100000 00000000 00100000 01100011 Emphasis no emphasis Use knob to move decoding cursor CLEAR Figure 29 The Channel Status view binary mode 38 764 Digital Audio Monitor User Manual Operating Basics The User Data View The 764 User Data view is intended to display optional user information that may be embedded in the user bits of digital audio signals As this is written the 764 can only interpret and display data that is block aligned with the Channel status data the 764 cannot interpret IEC 908 Compact Disk user data Press CLEAR MENU if necessary to exit a menu then the VIEW USER DATA button to select the User Data view User data may be displayed either in Hexidecimal form or as the equivalent ASCII text The Text mode is shown in Figure 30 Select the desired format by pressing the appropriate soft key The Hexidecimal dis
76. ng 40 flow control 58 G General commands 67 103 Index Get commands 68 H headphones 7 selecting channels 48 Headphones submenu 48 56 IEEE 152 1991 44 Ignore Validity Bit 52 Inputs digital audio 3 configuring 10 LTC 5 reference 5 RS 232 6 SER VIDEO Option 01 89 submenu 56 VITC 5 interpolation oversampling 50 K knob icon 10 knobs BRIGHTNESS 18 multi function 17 VOLUME 18 L Level Meters submenu 48 level meters 18 0 dB mark 51 ballistics 19 50 CLIP flag 22 display mode 49 104 interpolation oversampling 50 peak hold time 51 scale 19 20 22 true peak indicator 21 Lissajous pattern 27 MENU button 10 18 Menu commands 70 Menu HELP messages 10 Menus general techniques 10 METER SCALE buttons 17 MUTE indicator 21 MUTEs message persistence 52 samples required 51 N No Reference Signal message illustrated 32 O OFFSET button 17 Option 01 7 56 89 Option 02 4 93 outputs analog audio Option 02 93 RS 232 6 VGA video 5 P peak program level 20 51 phase display algorithm 46 buttons 16 764 Digital Audio Monitor User Manual Index channel pairing 16 format 26 54 submenu 54 PPM meter ballistics 43 Press commands 70 Product Support xii R reference inputs 5 reference level 44 See also test level Remote command abbreviation 66 command syntax 66 control 6 62 66
77. no loop through Range 250 mMVp p to 10 Vp p Table 23 Interface parameter measurements Characteristic Performance require Supplemental information ments Sample rate Range 27 kHz to 52 kHz Resolution 0 01 kHz 76 764 Digital Audio Monitor User Manual Appendix A Specifications Table 23 Interface parameter measurements Cont Characteristic Accuracy Synchronization Range Accuracy Indication Performance require Supplemental information ments Within 01 kHz 40 of dig audio frame 2 of digital audio frame Frame Sync Err Session view Table 24 Headphone output Characteristic Output voltage Frequency response Balance Distortion Table 25 VGA output Characteristic Resolution Signal Level Voltage White Black Blanking Horizontal Sync Vertical Sync Performance require Supplemental information ments into 150 Q load 0 dBFS input 20 Hz to 20 kHz 2 dB 0 5 dB THD N lt 0 05 20 kHz measurement bandwidth Information 640 X 480 VGA 0 7V 0V 0V TTL low true TTL low true 764 Digital Audio Monitor User Manual 77 Appendix A Specifications Table 25 VGA output Cont Characteristic Load Impedance Red Green Blue Horizontal Sync Vertical Sync Timing F requency Dot Clock Horizontal Rate Vertical Rate Pin Assignments pin WO oO N OcU amp S WN Fe m me eae eae eae uo Be WN F Information 75 ohms 75 ohms 75 o
78. onization is achieved or until Suppress Sync Loss Flags is set in the Level Meters submenu V BIT Location In bar Indicates that the Validity bit is set high for one or more data samples In the AES EBU standard a set validity bit indicates that the sample is not suitable for conversion to audio By default The meter bars and phase display treat the affected samples as a zero samples When Session is running the instrument counts invalid samples and displays the current total on the Session display You can suppress the V BIT message by setting the Ignore Validity Bit item in the Level Meters submenu to YES If you do so the 764 will treat all samples as valid and the word off will appear in the Invalid samples fields of the Session display This feature is included because the use of the Validity bit varies despite its official meaning as specified in the AES EBU standard and you may find it desirable to monitor audio from invalid samples 88 764 Digital Audio Monitor User Manual Appendix C Options This section describes the following options available with the 764 Digital Audio Monitor m Option 01 Embedded Audio Input m Option 02 Analog Line Output see page 93 m Power cord options see page 99 Embedded Audio Input Option 01 Option 01 provides the ability to monitor AES EBU digital audio that is embedded in serial digital video The option available both factory installed and
79. onstantly changing sync error the 764 detects this and displays the appropriate SYNC ERR flag s at all times not just when the error exceeds 25 Both the No Reference Signal message and the SYNC ERR flags may be suppressed through the Level Meters submenu refer to page 52 for details 764 Digital Audio Monitor User Manual 33 Operating Basics Session Reports 34 The 764 can output the data collected during a session in the form of ASCII text session Reports through the rear panel RS 232 connector You can print reports on a serial printer or save them to files on an IBM compatible Personal Computer PC The 764 can generate two types of session report short Figure 26 and long Figure 27 Tektronix 764 Session Screen Report short report Title Date Time Code used Session HH MM SS Starting time 00 00 00 Ending time 00 00 41 Elapsed time 00 00 41 Settings Display Mode 4 Channels Interpolation ON Ballistics TRUE PEAK Peak Program Level dBFS 8 Test Level dBFS 18 Consecutive full scale samples for clip 1 Consecutive zero samples for mute 10 De emphasis used on channel 1 NONE De emphasis used on channel 2 NONE De emphasis used on channel 3 NONE De emphasis used on channel 4 NONE Channel 1 Channel 2 Channel 3 Channel 4 Sr eees toe ssse case cose essee Possess cb reso spo es osc sso se ec ospo ene Highest True Peak Reading 0 7 0 0 0 dBFS eenacenenen
80. or day to day operation of the 764 Begins on page 13 Reference Begins on page 43 Appendices Instrument characteristics Options Accessories User Service Begin on page 75 Glossary Begins on page 101 Index Begins on page 103 Contacting Tektronix xii Phone Address Web site Sales support Service support Technical support 1 800 833 9200 Tektronix Inc Department or name if known 14200 SW Karl Braun Drive P O Box 500 Beaverton OR 97077 USA www tektronix com 1 800 833 9200 select option 1 1 800 833 9200 select option 2 Email techsupport tektronix com 1 800 833 9200 select option 3 1 503 627 2400 6 00 a m 5 00 p m Pacific time This phone number is toll free in North America After office hours please leave a voice mail message Outside North America contact a Tektronix sales office or distributor see the Tektronix web site for a list of offices 764 Digital Audio Monitor User Manual Getting Started This section contains information you ll need to put your 764 Digital Audio Monitor into service For a detailed description of instrument capabilities and instructions for its use refer to the Operating Basics section of this manual Unpacking Please save the packaging material in case you must later ship the instrument for calibration or service The following accessory items are included with the 764 Digital Audio Monitor m This
81. outputting a session report to a PC select the highest baud rate available in both the 764 and the PC then if you experience difficulty with flow control between the 764 and the PC set both to the next lower baud rate available and try again Copy The Copy submenu item determines the type of report that is output when you press the Copy soft button see Figure 23 When NO REPORT is selected the Copy function is removed from the third soft button and you cannot output a Session Report 764 Digital Audio Monitor User Manual Reference Peak Reading Interval sec Use this item to choose the duration of the peak reading intervals When a session is running the 764 stores the time and value of the highest true peak and meter bar readings encountered during each interval The time stamped peaks are included in a long report see Figure 27 on page 35 m This setting does not apply to error events clips mutes Invalid samples Parity Errors and Code Violations m Program peaks are not stored when the setting is 0 zero m Peaks are time stamped with the time Session VITC or LTC that has been selected through the Time Code submenu The length of time you may accumulate session statistics depends on this setting and the number of error events that occur Assuming few clips mutes or other errors the 764 has enough memory for at least 30 minutes of records when the interval is set to 1 second and over 30 hours when
82. play format has room for data from all four input channels the Text display shows two channels at a time In the Text display press the top CHAN soft button to toggle between the two input channel pairs 1 amp 2 and 3 amp 4 USER DATA ASCII Text Display Channels 1 amp 2 Channel 1 Data 222 222222 2222222222222 Channel 2 Data i aaa aa a aa a a a a a a a a Figure 30 The User Data view text mode 764 Digital Audio Monitor User Manual 39 Operating Basics Saving and Restoring Setups 40 The 764 automatically stores current front panel and menu settings in non volatile RAM The instrument restarts every time in the Audio View Session Display with the session stopped and session time if it is the current Time Code selection reset to zero All other settings will be as when the 764 was switched off For added flexibility you can also save up to three instrument configurations recall them later or restore the factory default settings with the techniques described next Saving a Setup You can save up to three additional instrument configurations in NVRAM for convenient later recall through the Save Setups submenu To do so 1 Configure the instrument as desired with the front panel controls and through the various submenus 2 Enter the top menu Press CLEAR MENU then MENU to enter the top menu anytime the 764 is operating 3 Use the multi function knob to scroll the menu highlight to S
83. r details on installing the product so that it has adequate cooling ventilation 764 Digital Audio Monitor User Manual vii General Safety Summary Use in a Proper Environment Do not operate this product in wet damp locations conditions or in explosive atmospheres Observe All Terminal Ratings To avoid fire or shock hazard observe all ratings and markings on the product Consult the product manual for further ratings information before making connections to the product Safety Terms and Symbols viii Terms in this Manual These terms may appear in this manual WARNING Warning statements identify conditions or practices that could result in injury or loss of life CAUTION Caution statements identify conditions or practices that could result in damage to this product or other property Terms on the Product These terms may appear on the product DANGER indicates an injury hazard immediately accessible as you read the marking WARNING indicates an injury hazard not immediately accessible as you read the marking CAUTION indicates a hazard to property including the product 764 Digital Audio Monitor User Manual General Safety Summary Symbols on the Product The following symbols may appear on the product 5 A p DANGER Protective Ground ATTENTION Double High Voltage Earth Terminal Refer to Insulated Manual 764 Digital Audio Monitor User Manual ix General Safety Summary X 764 D
84. rds Some experienced recording engineers prefer a higher alignment level than 18dBFS to make fuller use of the available coding range for a better S N ratio Others are more conservative For example SMPTE in RP 155 90 recommends a reference level of 20 dBFS And of course digital purists may always select True Peak ballistics In Bar Warning Messages The in bar warning messages for example INPUT UNLOCKED in the Channel 3 and 4 meter bars in Figure 32 are listed below in order of error condition priority Higher priority errors preempt lower priority ones Messages or Flags are displayed for as long as the error condition lasts plus n seconds where n is the CLIP MUTE hold time set through the Level Meters submenu see page 52 The INPUT UNLOCKED and LOW COMNFidence flags will always appear in both bars of the affected input all other messages can appear in one or both bars depending on channel content INPUT UNLOCKED The 764 is not locked to an incoming signal on the indicated input channel Data cannot be decoded all data and all other errors are ignored This message will appear when no input signal is present 764 Digital Audio Monitor User Manual Reference CODE ERR A bi phase coding violation ERRor has occurred in the digital data stream All affected data samples are unreliable and are therefore ignored The instrument treats affected samples as zero samples for use by the me
85. re than two button presses away 1 Press the CLEAR MENU button to exit any on screen menu 2 Press the VIEW AUDIO button 764 Digital Audio Monitor User Manual 13 Operating Basics 14 The left portion of the Audio view display always contains four bar graph level meters The right portion contains either a numerical display of session statistics see Figure 12 or the Phase display shown in Figure 13 Configure the right side of the Audio view display with the three PHASE DISPLAY buttons A B and SESSION Session 00 00 00 00 SESSION STATISTICS Channel 1 2 4 Highest true pk Highest bar rdg 0 No of clips No 117 of mutes Invalid O samples 0 Parity Errors 0 Code violations 0O Active Bits 24 DC offset 90 90 Sample rate 48 00 Frame Sync Err 0 0 b JOmMANOF2cSH cuz Iii l N P U T U N L Oo Cc K E D 3 CLEAR MENU Figure 12 The 764 AUDIO SESSION view The 764 has many options that affect the appearance and behavior of the Audio view features For more information refer to The Level Meters beginning on page 18 Sum and Difference Bars on page 25 The Phase Display on page 26 and The Session Display on page 29 Session Reports The 764 can also output session reports which are permanent records of session activity through the rear panel RS 232 port The reports can either be sent directly to a printer or captured on a PC and saved to disk This feature ad
86. reading interval through the Serial Port submenu for more information refer to Serial Port Submenu beginning on page 58 Be sure to set the Copy selection to either SHORT REPORT or LONG REPORT Run a session Stop the session but do not reset it Press the Copy soft button feature in Figure 23 on page 29 The 764 will send the report to the printer or PC indicating the remaining number of lines on the bottom of the display Press the soft button a second time to cancel the report 764 Digital Audio Monitor User Manual Operating Basics The Channel Status View The 764 Channel Status view displays the channel status information that is embedded in AES3 1992 professional or IEC 958 consum er digital audio signals Press CLEAR MENU if necessary to exit a menu then the VIEW CH STATUS button to select the Channel Status view You can choose to display the Channel Status in one of four formats fully decoded text the default illustrated in Figure 28 binary Figure 29 transmission order binary or hexidecimal To change display formats press the soft button assigned to the desired format as listed on the right side of the Channel Status View m In Text mode the Channel Status data is spelled out in plain English as shown in Figure 28 The 764 will decode embedded channel status data per AES3 1992 or IEC 958 depending on the state of the first transmitted channel status bit bit 0 of byte 0 Press the top
87. relation meter speed averaging intervals Speed Equivalent Speed Equivalent setting i interval s setting i interval s 1 1 0 0167 11 2 2 0 0333 12 3 0 0667 13 4 0 1333 14 5 0 2667 15 6 0 5333 16 7 1 0 17 8 1 5 18 9 2 0 19 10 2 5 20 764 Digital Audio Monitor User Manual 47 Reference Selecting Headphone Channels By factory default the headphone output follows the phase display That is you can listen to the audio programs that are currently driving the Lissajous pattern and Correlation meter refer to The Phase Display beginning on page 26 When you change the phase display channels either by selecting the other display pair A or B or through the phase display menu the headphone output will contain the audio on the newly selected input channels You can also configure the headphone output to listen to any two input channels you wish independent of the phase display selections Follow these steps to make manual headphone selections 1 Enter the top menu either by pressing MENU or the TOP MENU soft button if already in a submenu 2 With the multi function knob move the menu item highlight to Headphones Then press a soft button to enter the submenu 3 Set the Audio Source to MANUAL 4 Select the appropriate Manual Left Channel and Manual Right Channel 5 Press CLEAR MENU to exit the on screen menus and resume normal operation Submenus 48 The various 764 su
88. rements 764 Digital Audio Monitor User Manual 21 Operating Basics 22 Please be aware that although the peak indicators may reveal higher peaks than VU or PPM ballistics the indicators do act on the same processed data as the meters If interpolation is ON the peak indicators show peaks in the oversampled data and these peaks may be higher than those in the raw input data see Interpolation on page 50 If de emphasis AUTO CCITT J 17 or 50 15 is selected the peaks particularly at higher frequencies may be lower than in the raw data refer to The De emphasis Submenu on page 53 9 Clipping flag The clipping flag appears when the 764 detects clip ping and persists for the same hold time as chosen for the Mute indicator The user can specify the number of consecutive full scale samples that constitute clipping The range is from 1 to 100 samples Like the Mute indicator the clipping flag always reacts to unprocessed input data regardless of Interpolation or de em phasis settings Configuring the Level Meters You can configure the level meter scale with front panel controls Other meter characteristics such as ballistics scale units and program test levels are configured through the on screen Level Meter submenu Variable scale To adjust either the range or offset of the level meters press METER SCALE EXPAND or METER SCALE OFFSET then turn the multi function knob For best results and
89. s connected through one of the XLR inputs the program level should be shown in the corresponding meters If the input is through a BNC connector you must reconfigure the input with the following procedure before you can monitor the signal In either case please take this opportunity to familiarize yourself with the 764 front panel controls Figure 8 menu structure and techniques MENU Button Bas Multi function Knob Soft Buttons PHASE DISPLAY In SESSION O BRIGHTNESS VOLUME CLEAR MENU pe ies pe _ POWER Switch CLEAR MENU Q Osi Button STANDBY amp Figure 8 Controls for initial power up and configuration 764 Digital Audio Monitor User Manual 9 Getting Started Perform the following steps to select the input types and familiarize yourself with the 764 menu structure 1 Press the MENU button to enter the TOP MENU 2 When the 764 is in menu mode MENU provides access to context sensitive HELP messages Press MENU now to see the TOP MENU help message the display resembles Figure 9 Press the button again to clear the message Level Meters De emphasis Phase Display Headphones Inputs Time Code Serial Port Save Setups Restore Setups Screen Saver Service Press MENU SUBMENU Display Mode 4 Chan Interpolation ON Ballistics TRUE PEAK Peak hold time sec 4 Peak Program Level d Test Level dBFS 18 Set 0 dB Mark to DGT Consecutive FS Samp Consecutive 0 Samp
90. scale and offset by following the instructions under Configuring the Level Meters on page 22 You can also select appropriate meter response characteris tics ballistics and alignment levels refer to Level Meters on page 43 for more information Configure the Phase Display The phase display can show the phase relationship of any two channels in the selected channel group By default phase pair A is the first two channels in the group and phase pair B is the last two channels For example when the second channel group channels 5 through 8 is selected phase pair A is channel 5 left and channel 6 right and phase pair B is channel 7 left and channel 8 right You can specify any pairing of the four channels through the Phase Display submenu Refer to The Phase Display Submenu beginning on page 54 for information about specifying phase pairings setting the phase display orientation and setting the correlation meter speed Changes to the Session Statistics Display Because Parity errors code violations and frame sync errors have no meaning in embedded audio the corresponding fields of the Session display always contain n a to signify that the parameters are not applicable Additional Error Warning Messages There are two on screen error warning messages unique to Option 01 For more information about other error and warning messages refer to Appendix B Error Warning Messages No Video Input A No Video Input messag
91. sed to simple test tones with the 764 the pointer will usually read between 0 5 and 1 and will move as the correlation between the two channels changes Choose the time constant of the meter and thus the speed of meter response through the Phase Display submenu AGC AGC automatic gain control keeps the Lissajous pattern visible and within the bounds of the phase display for signal levels between 0 dBFS and approximately 40 dBFS When the AGC is Off full scale is equivalent to the Peak Program level refer to page 20 AGC does not affect the correlation meter Press the bottom soft button immediately above CLEAR MENU to toggle AGC On Off 28 764 Digital Audio Monitor User Manual Operating Basics The Session Display The session display is a dynamic readout of session history it is illustrated in Figure 23 When the 764 is in Audio view press the PHASE DISPLAY SESSION button to toggle between the Phase display and the Session display True Peak Session 00 00 00 00 Run KGI SESSION STATISTICS Channel 1 2 3 Highesttruepk O O 15 3 0dBFS Highest barrdg O 15 3 0dBFS No of clips No 117 23 0 0 of mutes Invalid O 11 0 samples 0o o0 0 Parity Errors 0o o0 Code violations O O0 24 dBFS Active Bits 20 20 24 90 kHz DC offset 85 85 90 Sample rate 44 10 48 00 Frame Sync Err 0 0 0 0 N mac ujonfj pn ea a Figure 23 The 764 AUDIO SESSION view Features of the Session Display
92. ssed under Cable Requirements and confirm the connection by downloading a session report to the computer or terminal Then refer to the Remote Control Commands section which begins on page 66 Cable Requirements The 764 is an RS 232 DCE device Table 15 lists the pin assignments of the connector When communicating with a DTE device that has a male 9 pin DB9 connector use a cable that connects pins 2 3 5 7 and 8 straight through example Tektronix part number 012 1445 00 To communicate with another DCE device use a null modem cable which swaps the lines between pins 2 and 3 and pins 7 and 8 Figure 35 and Figure 36 illustrate cable wiring for communi cating with a device that has a 25 pin serial connector Table 15 RS 232 pin assignments 764 DB9 pin Signal name Signal direction 1 optional 2 RXD Received Data From 764 3 TXD Transmitted Data To 764 4 optional 5 Signal Ground 6 optional 7 8 9 RTS Request to Send To 764 CTS Clear to Send From 764 optional 62 764 Digital Audio Monitor User Manual Reference NOTE RS 232 signals are named from the perspective of the DTE device Since the 764 is a DCE device pin 2 Received Data is an output from the instrument that is the data is received by the connected DTE device The 764 supports both hardware RTS CTS and software Xon Xoff handshaking choose the appropriate handshaking protocol through the Serial Port submenu S
93. t Figure 36 serial port Figure 37 Figure 38 Figure 39 Figure 40 List of Tables The 764 phase display aso 446 hacen sete ad wna The phase correlation meter The 764 AUDIO SESSION view The SYNC ERR Flags os i46 40 0sse0eeueaan Sync Error Reporting in the Absence ofa DAR A short session report 0 002 e eee Additional data on the long report The Channel Status view text mode The Channel Status view binary mode The User Data view text mode 6s lt 600 s 5 The Restore Setups submenu An in bar warning message The interpolation OFF message The De emphasis flags 0005 Connecting to a DTE device with a DB25 Connecting to a DCE device with a DB25 The Audio view with digital video input selected Option 02 connectors 550 96 4444448 Gh we beeen Standard balanced output pin assignments Connecting to an unbalanced input Table 1 Correlation meter speed averaging intervals Table 2 Level Meters submenu 2 00 Table 3 De emphasis submenu 20 5 Table 4 Phase Display submenu 4 Table 5 Headphones submenu 00 5 Table 6 Input submenu items standard instrument Table 7 Option 01 input submenu audio inputs selected 63 64 91 93 97 98 764
94. tal on the Session view You can suppress the V BIT message by setting the Ignore Validity Bit item in the Level Meters submenu to YES If you do so the 764 will treat all samples as valid and the word off will appear in the Invalid samples fields of the Session view This feature is included because the use of the Validity bit varies despite its official meaning as specified in the AES EBU standard and you may find it desirable to monitor audio from invalid samples Correlation Meter Algorithm The correlation meter reading is calculated 60 times each second from 9 second long blocks of interpolated 4x oversampled input data The formula used to drive the correlation meter is 4fs 60 S OR n 0 4fs 60 4fs 60 SOIS ay n 0 n 0 C sign X Where Js the sampling frequency in Hz for example 48000 L the value of the nth left channel sample and R the value of the nth right channel sample 46 764 Digital Audio Monitor User Manual Reference and 4fs 60 sign 1 if gt L R is gt 0 n 0 or 4fs 60 sign 1 if X LR is lt 0 n 0 The actual correlation meter reading is the rolling average of the last i sample blocks Ci G C where i is determined by the Correlation Meter Speed setting in the Phase Display submenu Table 1 lists i and the corresponding averaging interval for each meter speed selection Table 1 Cor
95. ter bars and phase display When Session is running the instrument counts code violations and displays the total on the Session view True Peak Sessic Highest Highest No of cl No of m Invalid s Parity Ei Code vic Active B DC offse Sample Frame o jomxoOrze so vz iifiii p fomxo00rze scvz iifii Figure 32 An in bar warning message PARITY The incoming subframe does not have even parity as specified by the applicable digital audio standards The data sample is unreliable and is ignored The meter bars and phase pattern treat the sample as a zero sample When Session is running the instrument counts parity errors and displays the total on the Session view LOW CONF Low Confidence This warning message indicates a marginal signal on the serial digital interface Problems that can trigger this message such as significant jitter or low signal amplitude will usually result in a poor eye pattern when the serial digital signal is displayed on appropriate equipment 764 Digital Audio Monitor User Manual 45 Reference V BIT Indicates that the Validity bit is set high for one or more data samples In the AES EBU standard a set validity bit indicates that the sample is not suitable for conversion to audio By default The meter bars and phase display treat the affected samples as a zero samples When Session is running the instrument counts invalid samples and displays the to
96. th professional AES EBU and consumer IEC958 formats These inputs have no provision for internal termination if the 764 is placed at the end of a signal path install a 75 Q end line termination Tektronix part number 011 0102 00 on the unused loop through connector An RCA phono plug to BNC male cable or adapter may be required to input consumer digital audio Plug is available in North America through Markertek Video Supply telephone 800 522 2025 CH3 4 Digital Audio SY A CH1 2 Digital Audio ON a Composite Video VITC Analog Audio LTC Digital Audio Ref DAR Figure 4 Connecting the standard 764 to your system 4 764 Digital Audio Monitor User Manual Getting Started NOTE The balanced XLR loop throughs are the default 764 inputs To receive a signal through the unbalanced BNC loop throughs or the optional serial video loop through Option 01 you must first reconfigure the instrument through the on screen menus Refer to Initial Power Up and Configuration on page 9 for instructions 2 Time Code Inputs VITC Reads vertical interval time code from NTSC or PAL analog video per IEC publication 461 specifications The time code can be shown on the SESSION display and stamped on each error on a printed Session Report The format of the Session View time display is Hours Minutes Seconds LTC Reads linear time code that also conforms to IEC specifica tions The ti
97. the peak hold time described below 764 Digital Audio Monitor User Manual Reference m Extended VU a VU meter as defined in IEEE 152 1991 but with an extended dB linear scale The 764 meter bars will also contain true peak indicators when Extended VU is selected and the display designation of this setting is vu Peak Note that this setting only affects meter performance when the input is live changing audio A constant 1000 Hz 10 dBFS tone for example will drive the meters to a constant 10 dBFS reading regardless of which Ballistics setting is selected Peak Hold Time Peak Hold time is the number of seconds that the true peak indicator see Figure 15 item 8 on page 19 remains at the most recent peak Set the hold time to 0 to turn the peak indicator Off Peak Program Level dBFS Peak Program level is the level relative to digital full scale that you choose as the maximum desired level for monitored programs The meter bars change to maximum brightness on the 764 display or red on an external VGA monitor above Peak Program level Test Level ABFS Test level is the level relative to digital full scale that you choose as the test or line up level for your system The meter bars change to medium brightness on the 764 display or yellow on an external VGA monitor between the Test and Peak Program levels Set 0 dB Mark to Use this item to number the meter scale relative to Dig
98. the SUBMENU function but you can press any soft button to enter the Inputs submenu After you do the display resembles Figure 11 5 To change the channel 1 2 input to the BNC connector press the soft button to the right of the BNC unbalanced choice The change is in effect when you exit the menu and return to normal operation 1 Because there are no other soft button assignments in the top menu level the 764 is configured so that pressing any one of the five soft buttons will select the highlighted submenu 764 Digital Audio Monitor User Manual 11 Getting Started CH 1 2 input BNC unbalanced CH 3A input BNC unbalanced XLR balanced Reference input BNC unbalanced BNC unbalanced TOP MENU Press MENU for additional information oe 3 NCW W Figure 11 The inputs submenu 6 Turn the multi function knob to move the menu highlight to the CH 3 4 input line 7 If desired change the channel 3 4 input to the BNC connector by pressing the associated soft button 8 Press the CLEAR MENU button to exit the menus and resume normal operation If you have selected the appropriate input type the corresponding level meters should now respond to the input audio program 12 764 Digital Audio Monitor User Manual Operating Basics This section contains the basic information needed to use your 764 The subsections are Overview Front Panel Controls The Level Meters The Phase Display The S
99. tice of the possibility of such damages Table of Contents General Safety Summary cece cece eccceees Preface vacua ine ewes oysters netre eeu es cer ev eave ewes This Manual sis deca acct Wea Dare te Aw Mie eee Gah we eG Bre Contacting Tektronix 1 3 50i 2o0c9o9esgdaveasudesoneeass Getting Started ssssssssosssesosssesossessoeoo Unpacki g ose sre lt 2 be asus den eyese seeds eeeuss avasre Mechanical Installation o13 003 24 oad cas edruboueaesass Connecting the 764 to Your System 1 Digital Audio Inputs and Loop Throughs 2 Time Code Inputs lt lt esaw nannu aes esed conse 3 Reference Nps 4 5c eedoabaaesae han eaeended 4 VGA Video Output 0 2 0 0 0008 5 RS 232 Communications Port 6 Optional Serial Video Loop Through He adpnlOnes 4 s40 heenes ashes cand e bade ndwe awe Supplying Power a lt h2 cp edna eee d coun eee ia Eeaaee eRe Initial Power Up and Configuration Operating Basics ic 6ho0 eee eee cineuiGewdscceirenseeaus OVEINIEW 252 6 4buge the te de eee ee ce PReee ate Ges ae Monitoring an Audio Program with the Audio View SESSION REDONS 264 s5ai 5 eeegdaddevdrcnendaesesa Monitoring the Ancillary Data Other Feattr S sn beg ce tee ded oe ick ost eeeesesiad a Front panel Controls iai5 as gosd anes cee et eas eeu ee Whe Level Meters 25s cniuxydee dar hanged vaaeeeeddi
100. ugh on screen menus Refer to The Phase Display Submenu beginning on page 54 for more information 764 Digital Audio Monitor User Manual Operating Basics The SESSION button selects a Session Statistics panel illustrated in Figure 12 Refer to The Session Display beginning on page 29 for more information Figure 14 764 front panel controls 4 METER SCALE buttons Use the METER SCALE buttons to change the Audio view level meter scale The default scale selected with NORMAL is illustrated in Figure 12 Use EXPAND and OFF SET with the multi function knob to configure the range and offset of the custom scale Refer to The Level Meters beginning on page 18 for more information 5 Multi function knob Turn the multi function knob to expand and offset the meter scale and to scroll various on screen menus The 764 Digital Audio Monitor User Manual 17 Operating Basics LED immediately above the knob will light and a knob icon will appear in the upper right of the display when the knob is active 6 MENU button Press MENU to invoke the display menu and call up context sensitive help text when a menu is on screen 7 Soft buttons The five white soft buttons are used to select choices or toggle settings that are indicated on the CRT display In Fig ure 12 for example the top soft button is used to toggle the Ses sion between Run and Stop 8 CLEAR MENU button Press CLEAR MENU to exit the on screen menu an
101. ument The AES XLR cable must be connected to either J913 or J914 use J914 for fixed analog audio output and use J913 for variable output If you move the AES XLR cable be sure to connect pin one of the cable connector to pin one on J913 or J914 Pin one is indicated by a triangular symbol on the circuit board and a triangular symbol and white dot on the cable connector 4 Reinstall the 764 in its enclosure and reconnect it to your system The appropriate analog audio cable connections depend on the analog output configuration Refer to Connecting the Instrument on page 97 for analog audio cable requirements 5 The audio input channels routed through the left and right analog line outputs are the same as on the front panel headphone output During manufacture the headphone output is set to follow the phase display You may manually select the headphone and analog line output channels through the Headphones submenu refer to Selecting Headphone Channels on page 48 for more information 96 764 Digital Audio Monitor User Manual Appendix C Options Connecting the Instrument The appropriate method of connecting the Option 02 analog outputs to your system depends on the configured output level and the requirements of your particular installation High level Balanced Output When using high level fixed or variable balanced output connect the 764 to your system with standard shielded XLR cables The analog line output polarity m
102. uts 0 2 to 10 Vp p Unbalanced inputs 50 MVp p to 2 Vp p Reference input Balanced input Connector type XLR terminated no loop through Input impedance 110Q 10 0 1 to 6 MHz Input level 0 6 to 10 Vp p Unbalanced input Connector type BNC terminated no loop through Input impedance 75Q 10 0 1 to 6 MHz Input level 0 2 Vp p t0 2 Vp p Sample rate locking range 27 kHz to 52 kHz all audio inputs 764 Digital Audio Monitor User Manual 75 Appendix A Specifications Table 21 Level Meters and Phase Display Characteristic Performance require Supplemental information ments Attack and Decay Ballistics only normal scale Characteristics does not comply with standards True Peak PPM decay characteristics No attack delay PPM per IEC 268 10A and IEEE std 152 1991 VU per IEEE std 152 1991 Level Meter accuracy 0 05 dB Steady 1 kHz tone Full Scale to 20 dBFS no de emphasis AGC Control Range 0 dBFS to 40 dBFS Lissajous pattern Table 22 SMPTE Time Code inputs Characteristic Information VITC Vertical Interval Reads NTSC and PAL VITC conforming to IEC publication Time Code 461 indicates time as Hours Minutes S econds Input connector BNC 75Q termination no loop through Input signal Video with VITC 1 volt nominal LTC Longitudinal Time Code Input connector Input signal LTC conforming to IEC publication 461 indicates time as Hours Minutes S econds XLR balanced 600 Q termination
103. value True Peaks will often be greater than the highest meter reading when Extended VU or PPM ballistics are used 764 Digital Audio Monitor User Manual 101 Glossary Test Level Also called alignment or reference level Usually the signal level used for system alignment In the 764 this setting determines the placement of level meter markers and a meter bar intensity color threshold 102 764 Digital Audio Monitor User Manual Index A accessories standard 1 AGC 28 alignment level 43 See also test level Audio view 13 ballistics meter 43 50 PPM 43 50 True Peak 44 50 VU 44 51 C cable serial communications 62 CCIR 645 43 Channel Status view 15 37 CLEAR MENU button 18 using 12 CLIP flag 22 CLIPs flag persistence 52 samples required 51 Command abbreviation 66 syntax 66 Contacting Tektronix xii controls 16 BRIGHTNESS knob 18 CLEAR MENU button 18 MENU button 10 18 METER SCALE buttons 17 EXPAND 17 764 Digital Audio Monitor User Manual OFFSET 17 multi function knob 17 PHASE DISPLAY buttons 16 SESSION button 16 TERM switches 3 VIEW buttons 16 VOLUME knob 7 18 Copy soft button 30 correlation meter 27 speed 55 D De emphasis submenu 53 defaults restoring 40 digital audio inputs 3 configuring 10 display mode 49 E EBU R68 1992 43 error messages See warning messages EXPAND button 17 F factory default settings restori
104. ware 2 Both 764 Digital Audio Monitor User Manual 73 Reference Table 19 Remote control MENU commands Cont Command Value setting Submenu item MENU BAUD lt 0 3 gt 0 38400 Serial Port Baud Rate 1 19200 Changing the Baud rate 2 9600 interrupts the remote connection 3 2400 MENU COPY lt 0 2 gt O No Report Serial Port Copy 1 Short Report 2 Long Report MENU PR INT lt 0 300 gt 0 to 300 seconds Serial Port Peak Reading Interval MENU SAVE lt 0 2 gt O Setup 1 Save Setups Last Saved 1 Setup 2 saves the current setup as 2 Setup 3 setup n MENU RESTORE lt 0 3 gt O Setup 1 Save Setups Last Restored 1 Setup 2 restores setup n 2 Setup 3 3 F actory Setup MENU SCRSVR lt 0 23 gt SS Screen Saver Delay in Hours MENU INFO lt 0 1 gt 0 S oftware Version Service Information 1 dentification Num MENU NUMERIC lt 0 1 gt 0 0FF Service Numeric Level Readout 1 0N MENU HOME Selects highlights the first item of the current menu or submenu 74 764 Digital Audio Monitor User Manual Appendix A Specifications Table 20 Digital audio inputs Characteristic Supplemental information ments Impedance Balanced inputs XLR Term switched in 110 5 0 1 MHz to 6 MHz Term switched out Return loss gt 30dB 0 1 MHz to 6 MHz Relative to 110 Q load at loop through connector Unbalanced inputs Return loss gt 30dB Relative to 75Q load at loop through connector Input level Balanced inp
105. y 764 Digital Audio Monitor User Manual 83 Appendix B Error Warning Messages CODE ERR Location In bar Code error A bi phase coding violation has occurred in the digital data stream All affected data samples are unreliable and are therefore ignored The instrument treats affected samples as zero samples for use by the meter bars and phase display The CODE ERRor indicator persists for the CLIP MUTE Hold Time set through the Level Meters submenu During a Session the instrument counts code violations and displays the current total on the Session display CRC Error Location Channel Status View lower left corner The Cyclic Redundancy Code calculated by the 764 does not agree with that calculated by the originating equipment and transmitted in Channel Status byte 23 of the digital input signal This discrepancy usually results from errors in digital signal transmission De emp Location Audio View above meter bar of affected channel De emphasis is in effect on the indicated channel Will appear above the affected meter bar when CCITT J 17 or 50 15 ms de emphasis is selected through the De emphasis submenu or when AUTO is selected and pre emphasis is indicated in the channel status bits of the input signal This message persists as long as the instrument is applying de emphasis to the input channel 84 764 Digital Audio Monitor User Manual Appendix B Error Warning Messages INPUT UNLOCKED

Tektronix 070-8811-08 Computer Monitor User Manual

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