Home

Envoy Product Manual

Contents

1. SECTION 4 POWER CONNECTIONS AUDIO CONNECTIONS SETTING UP THE ENVOY Attach the external power supply to the connector on the rear panel marked power If you wish route this cable under the plastic clip to provide a strain relief Attach the provided AC power cord to the power supply and apply AC power Turn the Envoy on using the rear panel power switch 0 off and 1 on The Envoy display should light up You will then see the introductory screen followed shortly by the status screen See page 17 to view this screen Inputs 1 2 amp 3 The Envoy has four inputs First we will tackle channels 1 and 2 which are microphone level only inputs As you look at the unit from the rear these are the 3 pin female XLR connectors farthest to the right Both channels operate the same way Connect your microphone to either of these XLRs and adjust your input level via the channel 1 or 2 input level control on the top surface The input level will be reflected on the VU meter Most users like to see a VU meter peak occasionally over the 0 mark which is the yellow LED on this meter Ifyou cannot achieve a good input level make sure the top surface button labeled murte AUDIO inputs is disengaged no red showing If that doesn t work you will need to try a different microphone or cable These inputs do not support microphones which require phan tom power Channel 3 input works much the same way but you can select whether you
2. Dx3 5 H Weight Net 3 lbs Shipping 8 lbs Coding Delay 6 mS BRI ISDN lines can be terminated by the telco on either a 6 pin RJ11C modular jack or an 8 pin RJ45 jack The Envoy ISDN U Interface con nector is an RJ11C connector If the telco provides an RJ11C jack then the standard modular telephone cord provided with the Envoy is the cor rect cable for connecting to the ISDN line If the telco uses an RJ45 jack the supplied cable will still work if care is taken to insert the 6 pin RJ11 plug into the 8 pin RJ45 telco jack exactly in the center leaving a spare pin on each side of the RJ45 jack Be certain that the pins are aligned correctly Alternatively custom RJ11 to RJ45 connecting cables can be ordered through companies such as Black Box Corporation 412 746 5500 or Digi Key 800 344 4539 Envoy Product Manual Envoy PINOUTS ISDN U Interface Physical RJ11C 6 pin modular jack Pin 3 Tip Pin 4 Ring Audio inputs Physical 3 pin female XLR Pin 1 Ground Pin 2 Audio In Pin 3 Audio In Audio outputs Physical 3 pin male XLR Pin 1 Ground Pin 2 Audio Out Pin 3 Audio Out Headphone outputs Physical 3 conductor 1 4 phone jack Tip L Audio Out Ring R Audio Out Sleeve Ground Contact Closures Physical 2 conductor 1 8 mini jacks Contact closures are floating Input controls have sleeve connected to Ground Power Physical 2 1mm i d 5 5mm o d coaxial Outer shie
3. What Every Broadcaster Needs to Know courtesy Douglas A Lane 1900 Woodland Drive North Reading MA 01864 7 digits local dialing number 10 digits area code local dialing number NI1 National ISDN 1 Ameritech Verizon Formerly Bell Atlantic Bell Canada Bell South Verizon NC Formerly GTE NC Verizon OR Formerly GTE OR Switch Type_ AT amp T 5ESS Custom AT amp T NI1 5E8 AT amp T NI1 5E9 DMS100 NI1 DMS100 Custom Siemens NI AT amp T NI1 DMS100 NI1 Custom ISDN AT amp T Point to Point AT amp T NI1 DMS100 NI1 DMS100 NI1 AT amp T NI1 DMS100 Custom DMS100 NI1 NI 1 DMS100 NI1 AT amp T NI1 AT amp T Custom SPID Format 01 7 digits 0 01 7 digits 011 10 digits 0111 10 digits 0111 10 digits 0 10 digits 0111 01 7 digits 000 10 digits 100 01 7 digits 0 no SPIDS or LDNs needed 10 digits 0000 10 digits 0001 7 digits 00 10 digits 0100 10 digits 34 or 4 10 digits 0100 10 digits 0 or 00 or 000 10 digits 0100 or 0000 01 7 digits 000 01 7 digits 0000 Envoy Product Manual Switch Type Pac Bell AT amp T Custom AT amp T NII DMS100 SNET AT amp T NI1 Custom SW Bell DMS100 AT amp T NI1 Siemens NI1 Qwest AT amp T NI1 Formerly US West AT amp T Custom SPID Format 01 7 digits 0 01 7 digits 000 note there may be different suffixes for the B1 channel and the B2 channel 10 digits
4. 1 B1 amp 2 B2 10 digits 10 B1 amp 20 B2 10 digits 100 B1 amp 200 B2 10 digits 1000 B1 amp 2000 B2 10 digits 01 B1 amp 02 B2 10 digits 010 B1 amp 020 B2 10 digits 0100 B1 amp 0200 B2 or 10 digits 1 01 7 digits 000 10 digits 0101 10 digits 01 10 digits 000 10 digits 0100 01 7 digits 000 or 7 digits 1111 or 10 digits 1111 01 7 digits O INTERNATIONAL A C Power A C adapter cords are available which will connect the standard IEC 320 Inlet Corps on the in line Envoy switching supply to a wide range of international power receptacles These may be purchased from Panel Components Corp PO Box 115 Oskaloosa IA 52577 0115 Tel Fax 800 662 2290 USA 515 673 5000 INT 800 645 5360 USA 515 673 5100 INT Web www panelcomponents com first html 41 42 Comrex Corporation SECTION 8 Asout ISDN ISDN stands for Integrated Services Digital Network and it is a special type of telephone system While most telephone lines are capable of carrying only analog audio ISDN lines actually carry high speed data Like plain old analog phone lines ISDN lines are linked between the telephone company and the customer premises via a single pair of wires called the local loop The signal carried on the local loop is fundamentally different than plain old telephone service and ordinary phones modems and fax machines will not work on them wi
5. Data Rate I28K Redial OK OAI Odial 01 20 4444 Cancel The Envoy has 20 memory locations which allow you to store a number and dial it quickly using the onzaz button To program your QuickDial memory press menu on the status display Then press conricure in the main menu fol lowed by paz options in the config menu Next select PRGRM opar from the dialer config menu Enter your memory index number 01 20 and then input the dialing number If a number was programmed into that Qdial location previously it will appear You may erase the number or backup if you make a mistake using the Back space key Press ox when your number is complete Press zxr until you reach the status display The QDial numbers will remain in memory even if the Envoy loses power Status Menu O Dial Switch NI I b Data Rate I28K Redial OK 25 26 Comrex Corporation PROGRAMMING ODIAL Place a Call Configure Test Exit Dial Options Network Info Test Exit Data Rate Prgrm Odial Test Exit Odial 01 20 key n number nou ox Back Space Cancel 4000 f ft 4444 008 4444 ft daar Envoy Product Manual LAST NUMBER REDIAL RECEIVING CALLS ANCILLARY DATA Redialing the last number is easy either press the repiaz key on the status display or the opz key and 00 The last number you dialed from the Envoy will be redialed This number will remain in memory after the Envoy is pow
6. Envoy or Comrex Nexus at the studio check the Locaz audio knob If it is turned up audio from the studio board will be sent back to the board and funny effects will result If you are doing a call in talk show on the road the remote people may com plain of hearing an echo when a caller is put on the air With the telephone pot down everything is OK The culprit is the telephone hybrid being used to put callers on the air Some of the remote audio is leaking through the hybrid and mixing with the caller audio Modern digital hybrids do a much better job of preventing this than the older units that had to be manually tweaked for each call If you are using a digital hybrid and having this problem dig out the manual and redo the hybrid s initial setup Some stations do not feed regular audio back to the remote particularly for sports broadcasts Instead they send a continuous feed ofthe board operator s microphone out to the game In this case the board op must remember to wear headphones and keep the studio speakers off His microphone would pick up the remote audio from the speakers and the crew at the game would hear themselves in delayed form 55 56 Comrex Corporation APPENDIX B FCC REQUIREMENTS This equipment complies with Part 68 of the FCC Rules On the bottom of the Comrex Envoy is a label that contains among other information the FCC Reg istration Number for this equipment The USOC jack required
7. a 3 pin male XLR The XLR connector is on the rear panel of the Envoy and the zocaz and RETURN level controls are on the top surface Use the same procedure outlined in the headphone section to set the correct levels at this port The audio feed from this output can be muted by pressing the MUTE AUX OUT button but first you must select whether the return audio local audio or both should be muted To do so press MENU from the status display Then press CONFIGURE and choose more Next select AUDIO IN OUT Press MUTE SWITCH and decide which audio you wish to mute The current selection will remain in memory until changed even when powered off and will be muted when the mure aux our button is depressed It is best when using professional audio gear to connect everything together using balanced audio connections Sometimes however it is unavoidable to connect to consumer equipment with unbalanced connections If you must use unbalanced audio here s how to connect to the Envoy Envoy inputs When driving the Envoy from an unbalanced source con nect pins 1 and 3 together on the Envoy input XLR This gets connected to the ground signal on your unbalanced device Connect pin 2 on the Envoy XIR to the unbalanced device s audio connection Envoy outputs The Envoy uses active balanced outputs designed to drive unbalanced sources directly This means there won t be any level difference when feeding an unbalanced source On the Envoy ou
8. connector on the rear of the Envoy In about one minute the ink DOWN status display should change to ox This means that the Envoy has correctly shaken hands with the telephone company along the ISDN line If the line is removed or the Envoy is turned off this handshake will need to take place again If the ox signal does not appear within about a minute refer to the Look for the Big OK section on pages 38 39 Status Menu Q Dial Switch NI I Data Rate I28K Redial Note The status display also shows the data rate see next section for programming and switch type selected ER Comrex Corporation SELECTING THE DATA RATE Now that the Envoy has been set up for your ISDN service you will need to tell it a few things about what you want to accomplish The first selection will be data rate The Envoy can communicate at four different data rates 56 64 112 or 128 kb s The 56 or 64 kb s data rates use only one B Channel and you will only be billed for one ISDN phone call at these rates The 112 and 128 kb s rates actually place two different calls between points using both B Channels although it looks to you like one call is placed and you will be billed for twice the connect charges Audio bandwidth varies with data rate At 56 and 64 kb s the Envoy carries 7 5 kHz audio bandwidth This is nearly transparent audio for voice applications although you might notice a slight cutoff at the ss sou
9. into SPID 1 and SPID 2 Now you will program the local phone numbers for your ISDN lines From the network configuration menu press Lpns to begin entering the LDNs After LDN 1 is programmed press ox The LDN 2 menu will appear After you have pro grammed LDN 2 press ox to return to the network configuration menu If LDNs were previously programmed into your Envoy they will appear If they are correct press ox until you return to the network configuration menu If you wish to change a previously programmed LDN or if you make a mistake while entering the number press Back space until the number is cleared and then enter the correct number b LDNS e Switch um Enter LDN OK Back Space Selection Stored Cancel Envoy Product Manual CONNECTING THE ISDN LINE Enter LDN 2 OK Back Space Cancel Selection Stored AAA 4404 Note The LDN is the Local Dialing Number for your line It is usually only seven digits long Do not include your area code in the LDN For example The Comrex ISDN Envoy test phone number is 978 772 9404 and the LDN is 772 9404 Some ISDN lines have a different number for each of the two channels some use the same number for both If you have only one number program it into both the LDN menus After the switch type SPID and LDN are programmed correctly press the exit key until you are again at the status menu Now attach the ISDN line to the telephone
10. must deter mine whether you want the headphone audio to be spur or mxEp The Envoy headphone outputs feed the user two different audio sources the first is called return which is all the audio being sent from the other end of the link The second is called rocar and contains all the microphone or line level inputs connected to the Envoy itself The Envoy can be configured to split the two sources by feeding local audio into the left headphone and return into the right or it can mix the two sources by feeding both left and right with the same mix Only one selection is allowed for all three headphones If you won t be listening to one of the audio sources we recommend the mx option so the remaining source will be fed to both headphone ears To select an option press the menu softkey on the status display to access the main menu Now select conr GurE From the config menu select wore Now select AUDIO IN our Then choose HEADPHONES Select the mix or spurr options here Your choice will remain in memory until it is changed even after the power is off You must have stereo headphones to use with the Envoy Plug the headphones into the 1 headphone jack Feed some audio into one of the inputs and get a good level on the VU meter Turn both headphone controls zocaz and RETURN for channel 1 all the way down First we ll set the level for the return audio then the local Press the menu softkey on the status display to access the mai
11. pair This can be useful when connect ing two local points where ISDN is not available but unloaded and unequal ized telephone loops pairs of wires are This mode is not for use on plain old subscriber telephone lines The service must be a simple pair of wires running from point A to point B these may exist already within your local telephone plant or may be purchased from the phone company as an un equalized broadcast loop or simply as an alarm pair There is a distance limitation in this mode and it depends on the gauge of wire used and other environmental factors In general use 18 000 feet as a limit when using typi cal telephone gauge wire In this mode one of your Envoys or a Nexus if that is what you are con necting with will be configured as the Master this Envoy Nexus provides the clocking signal to the wire and the other as a Slave this Envoy Nexus uses the clocking signal on the wire The units will provide a completely independent wideband audio channel in each direction on the single pair of wires To enter LDM mode select pm mope from the special modes menu It doesn t matter which unit you configure for MASTER Or SLAVE only that one is programmed as each Now you can attach the wire pair to the Envoy Nexus as you would an ISDN line using the center two pins ofthe RJ 11 connector Within about a minute the Envoy Nexus should wake up the ready lights should turn green and your audio link
12. should appear If either unit should lose power in LDM mode it will return to this mode when power is restored LDM mode is also a good way to prove out a pair of Envoys or an Envoy and a Nexus even without connection to ISDN You can simply connect an RJ 11 cable between your two units and when you enter LDM mode a connection will complete between the two STL Mode Udm Mode Ext DCE Exit Note The Envoy always connects at 128 kb s in LDM mode so the only con trol you need to preset is the ancillary data on off control As with ISDN this mode must be selected the same way on each Envoy 34 Comrex Corporation EXTERNAL DCE MODE This mode disconnects the terminal adapter from the codec inside the Envoy and allows you to connect to an external terminal adapter DSU satellite ter minal etc In this mode the Envoy works very much like a DXP1 or DXR 1 except that it will allow for ancillary data transmission The EIA530 connector may easily be adapted to V35 or X 21 via adapter cables available from Comrex The codec section will automatically detect the incoming data rate so it is not necessary to set it correctly on the Envoy If you are using ancillary data while in External DCE mode you need to set Anc Dat to ON see pages 27 28 before going into External DCE mode When External DCE mode is selected the Envoy screen will appear as below Press Cum at any time to leave External DCE mode The Envoy will automat
13. wish to feed a microphone or line level source into this input If you are connecting a microphone the switch next to the channel 3 input connector must be up Otherwise set the switch down and feed a balanced line level into the connector If your source is unbalanced read the section About Unbalanced Connections on page 15 In any case you will control the input level with the top surface Channel 3 input level knob until you get a good reading on the VU meter Input 4 Channel 4 has more options than the others To get started set the control switch furthest to the left on the rear panel to the down position This will make channel 4 a regular program channel Now select whether you will be feeding a mic or line level input into channel 4 and set the channel 4 mic line switch appropriately Now feed some typical audio into channel 4 and adjust the level on the VU meter using the channel 4 input level control on the top surface Ifyou plan on using channel 4 as a regular program chan nel you re done with your input audio setup If you d like to use channel 4 as a spotter or producer input move the control switch the one on the far left to the up position Channel 4 will now not be heard on air or seen on the VU but can be heard in the headphones 13 14 Comrex Corporation Headphone Outputs 1 2 amp 3 All work the same way so we ll describe headphone 1 operation and you can take it from there First you
14. 2Kb s 128Kb s Qdial 01 20 STL Mode Ldm Mode Ext DCE Enter SPID 1 Enter SPID 2 Enter LDN 1 Enter LDN 2 ATT 5ESS DMS100 Nat ISDN 1 Headphones Mute Switch Anc Data off Anc Data on Load Store Key in number now STL Mode Active Master Slave Ext DCE Mode Selection Stored Selection Stored Selection Stored Selection Stored Mix Split Mute Local Mute Rtrn Mute Both Load Profile 1 9 Store Profile 1 9 Envoy Product Manual SECTION 3 DIAGRAMS AND DESCRIPTIONS OF CONTROLS AND CONNECTORS TOP SURFACE DIAGRAM 6600000068 1 Inpur LEVEL CONTROLS 1 2 amp 3 8 MENU SOFTKEYS 2 RETURN AUDIO LEVEL FOR HEADPHONES 1 2 amp 3 9 Mute AUDIO In BUTTON 3 Locat Aupro LEVEL FOR HEADPHONE 1 2 amp 3 10 DiaLinG KEYPAD 4 HEADPHONE JACKS 1 2 amp 3 11 Mure Aux Our Burton 5 READY NDICATOR 12 Aux INPUT LEVEL CONTROL 6 CARRIER DETECT CD INDICATOR 15 RETURN AUDIO LEVEL FOR Aux Our 7 VU METER 14 Locat AUDIO LEVEL FOR AUX Our Comrex Corporation INPUT LEVEL CONTROLS 12863 RETURN AUDIO LEVEL FOR HEADPHONES 12863 LOCAL AUDIO LEVEL FOR HEADPHONE 1 263 HEADPHONE JACKS 1263 Reavy INDICATOR CARRIER Detect CD INDICATOR VU METER These knobs control the input audio level for audio channels 1 2 and 3 re spectively The knobs are color coded Adjust each mixer channel using these knobs until an appr
15. Basic Rate Interface BRI line with U interface reference point 2B10 line coding and either 2B D Service supports up to 128 kb s or 1B D Service supports up to 64 kb s Note We suggest that you order 2B D Service to allow maximum flexibility in using the Envoy since ordering 1B D Service will restrict the Envoy to 7 5 KHz audio bandwidth The Envoy supports the following switch types and software protocols e AT amp T 5ESS Custom 5E6 and later software e NTI DMS100 BCS 32 and later software Pvc1 e National ISDN 1 compatible may be a Siemens switch AT amp T 5ESS NI1 switch Northern Telecom PVC2 or other switch Request that the ISDN line allocate one DYNAMIC Terminal Endpoint Identi fier TEI per phone number 43 44 Comrex Corporation AT amp T 5ESS Custom SWITCH With an AT amp T 5ESS switch most telephone companies provide the option of Point to Point one telephone number which operates both B channels and no SPIDs or Point to Multipoint two telephone numbers and two SPIDs or Service Profile IDentifiers one for each B channel Either service may be used with the Envoy Request the following features Feature Value BI Service On Demand DMD B2 Service if two B channels are ordered On Demand DMD Data Line Class Point to Point or Point to Multipoint Maximum B Channels 2 if2B D lif 1B D Circuit Switched Voice Bearer CSV Channel Any Number of CSV calls 1 for
16. Envoy This is a toggle switch which will kill the audio feed provided on the aux our audio output on the rear panel Like the headphone channels this line level output is a user adjustable mix of local and return audio This button can be configured via the menu to mute only the return audio only the local audio or both This can be useful when the Envoy is connected to a PA system at a remote venue and you don t want some programming to be heard over the PA See Auxilliary Output on page 15 to configure this button This knob determines the input level for the audio at the aux n connector If this connector has been configured to be a main program channel the level will appear on the VU meter If the aux n has been configured as a producer spotter channel no VU indication will appear but the level control still adjusts this level into the headphones You may wish to set this level with the channel configured in the program mode then switch it to the spotter producer mode if desired See Input 4 on page 13 for details This knob controls the level of the audio present on the aux our connector that is sent from the far end of the link If you do not wish to hear any return audio from this output turn the knob all the way down The knob is color coded to coincide with the aux n knob This knob controls the level of the audio present on the aux our connector that is locally mixed within the Envoy including
17. Envoy ISDN Codec SECTION ebe Ae EE 4 Ds croate ENVOY FEATURES ease sara ses Edge edilenin ed inizi L SE WHAT COMES WITH THE ENVOY e A PR e H ABOUT THE ALGORITHM eee D P iie ERE TERMINAL REN P kai dah COMMAND PROCESSOR rss D PREIA EE UPGRADES tia ia Di EENVOY MENU SELECTION TREE esen 6 ES eee DIAGRAMS AND DESCRIPTIONS OF CONTROLS AND CONNECTORS sne 7 Set ed TOP SURFACE Ee a dan baml ilm DESCRIPTION OF TOP SURFACE CONTROLS AND INDICATORS 8 demek lamelli ds REAR PANEL DUGRAM rn LO R ae Gain DESCRIPTION OF REAR PANEL CONNECTORS 4 T e SETT NG UP EE 13 PRETE CORTEO TOR POWER CONNECTIONS us LD a AUDIO CONNECTIONS seren LD dc ABOUT UNBALANCED CONNECTIONS eee LD Seet degen BEFORE YOU EE DO Di CONFIGURING THE Em 17 S POWER UP Te e EE SELECTING THE SWITCH TYPE ANNER 17 siasi dada ENTERING THE SPIDS sss saatimi iaia LO eee ei ENTERINGTHELDNS e 20 decoradas CONNECTING THE ISDN LINE 21 TN SELECTING THE DATA RATE tia PO dee PIACING A CAD ii AA di di BE PE e ET PROGRAMMING RT PR LAST NUMBER REDIAL sisi sirin arma res ikea kanla amaa yandi LT NE RECEIVING EE amdan amal ANCILLARY E e ee ISDN LINE PROFILES en 28 a MENUS FOR LOADING AND STORING ISDN PROFLES 29 Oi ADDITIONAL FUNCI NS eii EEN NEESS EN 31 SE SPECIAL EE ed aa STE BACKUP MODE Saad OO EE LDM MODE sisi onc deeg dans id Comrex Corporation SECTION
18. SPID numbers are entered You will not be able to place calls in that case e If there has been a recent area code change at your location you may want to try both the new and old area codes e On pages 40 amp 41 we list some conventional wisdom about SPIDs and switches gleaned from many years of experience with ISDN Some of this information is becoming dated but it may be useful on older lines or in areas that are slow to update their ISDN practices e If none of this helps Comrex Tech Support may be the solution Remember though that we are quickly going to ask whether you have verified the line information with the telephone company so you should do that first Once you have the OK on the screen you should be able to place and receive calls Comrex Tech Support would be happy to help with these initial tests A frequent problem with new ISDN installations is being unable to place a long distance call Unless you have made arrangements with a long distance company to provide service on that line you may be in this position We strongly suggest using one of the major long distance companies for ISDN calling You may be able to temporarily make calls by entering the 1010 number for that company but it is usually best to actually sign up for service Here are some useful 1010 numbers e AT amp T 1010288 e MCI 1010222 e Sprint 1010333 39 Comrex Corporation Some Known SPID FORMATS Information from ISDN
19. Tama TROUBLESHOOTING vlan EE 35 OTP OCT ESS CODEC LOOPBACK EES E ge ee EXPECTED RESULTS IN CODEC LOOPBACK per BO EE TA LOOPBACK Soeren a a E o a BO PORTE ExPECTED RESULTS IN TA LOOPBACK mer DI BEE LOOK FOR THE BIG OK isc DO talar USING LONG DISTANCE ACCESS CODES e S ee SOME KNOWN SPID FORMATS iii 40 scada INTERNATIONAL A C POWER CORDS e AL A AB0UTISDN E 42 Os ORDERING ISDN isla lilla 43 EE alia ISDN SERVICE ORDER NFORMATION e AD grinin daime drees ATET SESS CUSTOM SWITCH 44 EE DMS 100 NORTHERN TELECOM SWIICH AD la CHECKLIST FOR ALL SWITCH rte AD 10 TECHNICAL RE 46 A RETE G7 22 ALGORITHM Ee At eege THEORY OF OPERATION NNN NNN DO Loria E Z iia INVERSE MULTIPLEXING eee 48 aaa ABOUT ANCILLARY Dam AD dedicadas TROUBLESHOOTING THE ANCILLARY DATA CHANNEL eee DL De RI ENVOY SPECIFICATIONS 0 Z EEE MY ISDN CONNECTION eridi adanada resi lades medala e ini Z SE Eege ENVOY PINOUTS EE E APPENDIX A ABOUT MIX e 54 APPENDIX B e ee 56 SCHEMATICS Envoy Product Manual About Comrex Comrex has been building reliable high quality broadcast equipment since 1961 Our products are used daily in every part of the world by networks stations and program producers Every product we manufacture has been carefully designed to function flawlessly under the harshest conditions over many years of use Each unit we ship has been individually and thoroughly tested Most items are
20. am transmission If you do not hear audio or it is distorted e Check your connections e Make sure the VU meter peaks occasionally over the 0 mark which is the yellow LED on the meter e Insure that the mic line switch is in the correct position If there is still a problem please contact Comrex to arrange for repair of the Envoy 37 38 Comrex Corporation LOOK FOR THE Bic OK Most problems with ISDN occur during the initial setup of the line In order for the Envoy work you must program some information specific to your ISDN line and there must be an OK message on the display If any other message appears the initial handshaking with the ISDN line has not been completed and a call cannot be made Prior to programming the Envoy you need some information from the telephone company This may have been written on the ISDN jack or on a tag or paper left by the installer If not you should contact the telephone company and ask for the following SPID Numbers You will usually be given two of these They normally contain the phone numbers of the two B channels of your ISDN line possibly with some extra digits before or after the number The most common format is XXX XXX XXXX 0101 where the X s represent the 10 digit phone number including area code Switch Type The Envoy has three choices for switch type NI 1 National ISDN 1 DMS 100 and 5ESS These refer to the type of switching equipment
21. arameters Keep in mind that the Envoy data channel is simply a pipe What bytes are sent and how they are interpreted is completely dependent on the software being used and how that software is configured Envoy Product Manual TROUBLESHOOTING THE ANCILLARY DATA CHANNEL The loopback testing facility in the Envoy can aid in troubleshooting ancil lary data connections It is often difficult to find a fault in a problem like this since the trouble could be at either end of the link By loopback testing the ancillary data channel on each end at least you can easily find which end has the trouble To loopback test ancillary data 1 Connect a computer serial port to the Envoy 2 Run a program on the computer with basic serial communications func tions like Procomm Windows Terminal or Win95 Hyperterminal 3 Set the communications parameters as follows 4800 baud 8 bits no parity 1 stop bit echo off half duplex mode in Hyperterminal 4 Make sure the software has the serial port chosen which is connected to the Envoy 5 If not already done configure the Envoy for ancillary data mode pages 27 28 6 Type some characters on your computer and verify that you do NOT see them on your screen 7 Go into the test menu on the Envoy and select TA Loopback The reapy and cp lights should come on 8 Type on your computer keyboard You should see your characters echoed back to you on the screen If this test i
22. available off the shelf either di rectly from Comrex or from our stocking dealers Comrex stands behind its products We promise that if you call us for technical as sistance you will talk directly with someone who knows about the equipment and will do everything possible to help you Ourtoll free numberin North America is 800 237 1776 Productinformation along with engineering notes and user reports are available on our website at www comrex com Our E Mail address is info comrex com Warranty and Disclaimer All equipment manufactured by Comrex Corporation is warranted by Comrex against defects in material and workmanship for one year from the date of original purchase as verified by the return of the Warranty Registration Card During the warranty period we will repair or at our option replace at no charge a product that proves to be defective provided you obtain return authorization from Comrex and return the product shipping prepaid to Comrex Corporation 19 Pine Road Devens MA 01434 USA For return authorization contact Comrex at 978 784 1776 or fax 978 784 1717 This Warranty does not apply ifthe product has been damaged by accident or misuse or as the result of service or modification performed by anyone other than Comrex Corporation With the exception of the warranties set forth above Comrex Corporation makes no other warranties expressed or implied or statutory including but not limited to warranties of merchantabili
23. channels 1 3 and aux wn if it is configured as a program channel Comrex Corporation 10 REAR PANEL DIAGRAM 15 CHANNEL 1 INPUT MICROPHONE CONNECTOR 16 CHANNEL 2 INPUT MICROPHONE CONNECTOR 17 CHANNEL 3 INPUT CONNECTOR 18 POWER CONNECTOR STRAIN RELIEF 19 CHANNEL 3 Mic Line SWITCH 20 POWER JACK 21 STL CLOSURE 22 READY CLOSURE 23 ISDN U INTERFACE 24 ANCILLARY DATA 25 Aux OUT CONNECTOR 26 Aux IN Mic Line SwrrcH 27 Aux IN CONNECTOR 28 Aux IN CONTROL SWITCH 29 EXTERNAL DCE 30 Power SWITCH Envoy Product Manual 15616 CHANNEL 1 amp 2 Input Mic CONNECTORS 17 CHANNEL 3 NPUT CONNECTOR 18 POWER CONNECTOR STRAIN RELIEF 19 CHANNEL 3 Mic Line SWITCH 20 POWER Jack 21 STL CLOSURE 22 READY CLOSURE 23 ISDN U INTERFACE 24 ANCILLARY DATA 25 AUX OUT CONNECTOR These 3 pin female XLR connectors are designed to accept balanced micro phone level audio feeds The input level for these channels is adjustable via the knobs in the left and middle positions as shown in 1 of the Top Surface diagram on page 7 This 3 pin female XLR connector is designed to accept a balanced microphone or line level audio feed The input level for this connector is adjustable via the top surface control in the right position as shown in 1 of the Top Surface diagram on page 7 The level is selectable between nominal mic or line lev
24. ctive only a small fraction of the time During a file download however the link will most likely be constantly active with one byte being sent immediately after the next unless flow control is active The Envoy audio algorithm operates in one of three possible modes It either formats its audio data into 8 7 or 6 bit words Without ancillary data engaged the Envoy forms its codewords into 8 bit words at 64 and 128 kb s and 7 bit words at 56 and 112 kb s With ancillary data engaged the codewords are each sliced by one bit i e 7 bits at 64 128 and 6 bits at 56 112 in order to make enough room to imbed the data This slicing is done whether or not the ancillary data channel is active or idle and the audio quality is reduced very slightly with a smaller codeword 49 50 Comrex Corporation Here is a description of a typical ancillary data hookup Each Envoy or Nexus operator will configure his unit for operation at the desired bitrate and engage the ancillary data function The call will be completed Each operator will attach a PC com port to the ancillary data connector on the Envoy via a straight through 9 pin cable and load a terminal emulation program like Windows terminal or Procomm Each will set the correct com port in soft ware and set the communications parameters to 4800 baud 8 bits no parity one stop bit Flow control should be turned off In most ways the link will resemble a normal modem conn
25. d to reprogram the line informa tion unless you move it to another ISDN line Note Ifyou are installing the Envoy for a full time application we recommend protecting it with an uninterrruptible power supply UPS with built in surge protection A model in the 250 watt category should be fine and prices are now less than 100 They are available from computer and electronic stores Envoy Product Manual SECTION 5 Power UP SEQUENCE SELECTING THE SWITCH TYPE CONFIGURING THE ENVOY When the Envoy is connected to power and turned on the self test menu appears for approximately thirty seconds The Envoy then shows the status display The main setup options are displayed in the lower left portion of the screen As shipped from the factory the Envoy status display will be the same as the screen shown below These selections will remain in nonvolatile memory until changed Self Test Status Menu Q Dial Switch NI I Data Rate I28K Redial Link Down 4000 4404 The telephone company will need to tell you the switch type so you can select it here This describes the type of equipment on the telephone company s end of the ISDN line The choices are AT amp T 5ESS Northern Telecom DMS100 and National ISDN 1 NI1 Note that the AT amp T and Northern Telecom switches often work in NI1 mode so if this is the case NII is the correct choice 5ESS or DMS100 should be selected only if the telephone company has specif
26. e tween the two numbers it possesses This difference is what the transmitter sends to the receiver The receiver uses this difference to calculate the true value Since the difference signal contains less than the data sample data rate is conserved In human speech and most other audio much more energy exists in the lower part of the audio spectrum than in higher freguencies Therefore the codec reproduces audio more accurately at the lower end than at the higher end Using digital filters audio is divided between high andlow sub bands and each sub band is sent through the encoder decoder combination separately The lower band can then use up the majority of the bits available leaving only a few for the relatively less complicated high band Discrete time sampling and guantization of an analog waveform is known as Pulse Code Modulation PCM Since the codec algorithm uses differences between samples and since the predictors adapt automatically with changing values of previous input samples we call the algorithm used Adaptive Differ ential PCM or ADPCM When we add the concept of dividing and conquering individual bands the process becomes Sub band SB ADPCM SB ADPCM is defined as a international standard by the CCITT as recommendation G 722 The text of this specification is public information and is a good source for further information on this algorithm The transmitting codec forms its outgoing data into words each consis
27. e Suitable for connection to a PA system it can be selectively muted via the top surface MUTE AUX OUT control see Auxilliary Output 4 on page 15 11 12 Comrex Corporation 26 27 28 29 20 AUX IN Mic Line SWITCH AUX IN CONNECTOR AUX IN CONTROL SWITCH EXTERNAL DCE POWER SWITCH When this switch is up the aux IN connector 27 is configured to receive a microphone audio level 80 to 40 dBu When this switch is down the AUX IN is configured to receive a line level 10 to 4 dBu At either setting the level is adjustable via the aux IN control knob on the top surface This is a 3 pin female XLR connector suitable for balanced mic or line level audio dependent on the setting of switch 26 It can be used as a main program channel or as a spotter producer input dependent on the setting of switch 28 If this switch is up the audio present at the aux IN connector is not heard on air Instead it is heard only in the headphones This is useful if a producer or spotter is present who is to be heard only by the people on air If this switch is down aux iv becomes a 4th program channel and functions just like the channel 3 input This port allows you to bypass the terminal adapter inside the Envoy and connect to an external terminal adapter DSU satellite terminal etc 0 off 1 on These markings are screened directly on the rocker switch Envoy Product Manual
28. e a Call Configure Test Exit Dial Options Network Info More Exit Data Rate Prgrm Qdial Special Exit Select a Data Cancel Selection Stored TTI f ft 008 4444 4444 4444 23 Comrex Corporation PLACING A CALL There are two ways to place a call with the Envoy You can dial manually or use the Quick Dial option for automatic dialing To manually dial select menu from the status display Press PLACE A carr from the main menu and key in the number you wish to call Press the ox key to start dialing If you make a mistake simply press BACK SPACE until the number is cleared and then enter the correct number If at any point you wish to terminate the call simply press the wancup key C f Status Menu Q Dial Switch NI I Data Rate I28K Redial A i Place a Call Configure Test Exit 4444 A key n number now ER Back Space 4444 Cancel Note ISDN dialing numbers use the same local and international access and area codes as normal analog calls i e if you use a 1 before a number for a normal long distance call use a 1 before the ISDN number 24 Envoy Product Manual PROGRAMMING ODIAL To place a QDial call simply press the opr key on the status menu and then enter the QDial number 01 20 that you wish to dial Your call will complete momentarily Programming QDial is discussed below Status Menu LD Q Dial Switch NI I b
29. ection When a key is typed on one terminal the ASCII byte corresponding to that character will be sent out the computer com port to the Envoy The Envoy will embed this character into the data it is sending and the Envoy on the far end will extract this character from the incoming data It will then send the character to the other computer com port and it will appear on the other display Of course since the channel is full duplex this exchange may be happening in both direc tions simultaneously A few common options in terminal programs will ease communication a Local echo Engage this ifyou wish to see what you are typing on your own display The Envoy cannot echo the characters you send back to your display only send them to the other end You must configure your communications program to do this b Cr gt CR LF When you type a carriage return enter key the CR character is all that is usually sent through the Envoy data link Your program will likely interpret this correctly and send the cursor back to the beginning of the same line Your program can probably be set to interpret the CR character as both a CR and IF line feed sending the cursor to the beginning of the next line Your program can also usually be altered to send both characters when the enter key is pressed Usually only one of the above options is required c Other options The software setup of your communications program may require additional p
30. ed bit stream and converts it to analog audio In the Envoy codec the analog audio inputs and outputs are available to the user The input and output compressed bit streams are con nected internally to the terminal adapter section There are different types of compression and the type is often defined by the name of the algorithm employed The Envoy uses the international standard G 722 algorithm and it is also capable of a higher speed version of G 722 which provides 15 kHz bidirectional audio at 112 128 kb s For more information on this subject see the G 722 Algorithm section on page 46 We call this the TA for short This section can be thought of as a modem but one that only works on a special type of telephone line This line is called an Integrated Services Digital Network line or ISDN A description of this ser vice is included on page 42 The TA takes the encoded audio from the codec and feeds it to the telephone line It also feeds audio data from the phone line to the codec It allows you to dial and answer ISDN phone calls and provides the functions required to handshake with the ISDN line as well as to troubleshoot problems should they occur The TA in the Envoy includes a section called the NT1 which is a conditioning circuit that interfaces with the phone line This eliminates the requirement for another external box on your circuit The Envoy TA also can combine the two ISDN B channels using an inverse mult
31. el via the associated switch see 19 This built in clip is designed to sit over the cord feeding the power connector providing protection against the connector pulling out if someone should tug on the cord To use it simply feed the power cable under the clip before connecting it to the Envoy This switch determines whether audio input 3 is configured to receive a mi crophone level 80 to 40 dBu or line level 10 to 4 dBu audio input This is a 2 conductor barrel connector designed to mate with the Envoy power supply module Be sure to attach only the power supply provided from Comrex here The Envoy requires 5V on this connector This mini jack is a dry contact closure which triggers closed when the Envoy S N STL BACKUP MODE This mini jack provides a dry contact closure when the digital audio decoder achieves synchronization with an incoming digital audio signal i e when the decoder is decoding audio This closure follows the rzapy light next to the front panel display This RJ 11C modular jack is for attaching the ISDN line from the outside world to the Envoy This 9 pin female connector provides connection for a 4800 baud ancillary data channel enabling data communications while broadcasting This 3 pin male XLR output provides a mix of codec return and local audio from the Envoy It is a balanced line level audio feed whose level is adjust able via the aux OUT RETURN and Aux our LOCAL knobs on the top surfac
32. ered down As long as your options are set to be compatible with the incoming device the Envoy should automatically answer the incoming call and wake up providing full duplex audio Ancillary data provides a low speed data channel along the same ISDN phone call used for the coded audio It has little impact on the audio quality and allows two computers or other asynchronous devices to communicate at 4800 baud The 4800 baud rate is fixed regardless of the data rate selected The one thing to note about ancillary data is that both Envoys or an Envoy and a Nexus MUST be configured the same way with ancillary data on or off If the ancillary data mode is mismatched between two Envoys or an Envoy and a Nexus the audio channel will not work correctly If communicating to a compatible device which is not an Envoy or Nexus the ancillary data mode must always be off To set this mode select menu from the status display Then select CONFIGURE from the main menu From the config menu choose more Then select anc DATA Finally select ANC DATA ON OF ANC DATA OFF If you have selected anc DATA ON this will be indicated on the status display Press ver until you return to this display Configuration and connection of ancillary devices is covered in the About Ancillary Data section on pages 49 51 Status Menu D lt O Dial Switch NI I Data Rate I28K Redial OK Place a Call Configure Test Exit AAA 444 27 Co
33. figure Test Exit Dial Options Network Info More Exit Audio in out Anc Data Profiles Exit Profiles AA f ft fh 4444 ant AAA 40400 29 30 Comrex Corporation Choose Load or Store and the screen will look like one of the two below Once you have selected a profile number the screen will store load all of the preset parameters Store Profile 1 9 Cancel Load Profile 1 9 Cancel 008 AAA Repeat all of the above steps to store and load multiple profiles You may wish to attach a label to the Envoy indicating which profile index number applies to which ISDN location Envoy Product Manual SECTION 6 SPECIAL MENU ADDITIONAL FUNCTIONS The Envoy has three special operational modes STL Backup Mode Limited Distance Modem Mode and External DCE Mode To access these modes press MENU On the status display Then select conrIGURE in the main menu followed by DIAL OPTIONS in the config menu Next press specIAL in the dialer config menu Choose the appropriate mode from the special modes menu These modes are explained in detail after the diagrams Status Switch NI I Data Rate I28K OK A f Place a Call Configure Test Exit f ft Dial Options Network Info More Exit Data Rate Prgrm Odial Special Exit fh STL Mode Special Ldm Mode Modes Ext DCE Exit AA 4000 4000 4000 4 Note While these special modes are engaged the other me
34. h signifies it has locked onto the incoming digital audio signal This will usually light up a few seconds after connection and will go out if the codec loses sync for any reason A contact closure which follows this indication is available on the rear panel When the Envoy receives an incoming call this carrier detection light will be on steady indicating that the terminal adapter has established a connection with another compatible codec At this point audio is not yet being encoded and decoded This provides an indication of the audio level being fed into the Envoy It doesn t mirror the receive audio in any way Most users set input level so the VU peaks just over the 0 mark which is the yellow LED on this meter 10 11 12 13 14 Envoy Product Manual MENU SOFTKEYS MUTE Aupro IN DIALING KEYPAD Mute Aux Our AUX INPUT LEVEL CONTROL RETURN AUDIO LEVEL FOR AUX Our LOCAL AUDIO LEVEL FOR AUX Our These work like the buttons on an Automatic Teller Machine Depending on your menu selection one or more of the keys will offer you the different choices in that menu This is a toggle switch which kills all audio going into the Envoy when activated It can be used as a cough switch or simply a way to keep your conversations private during a break When this button is depressed the VU meter will no longer show the input audio level for any input channel Use this keypad to place calls with the
35. ically return to this mode if power is lost STL Mode Special Ldm Mode Modes Ext DCE exit ft Ext DCE Mode Exit 9008 4404 Note External DCE mode provides access to the codec section not the TA sec tion The Envoy cannot be used as a stand alone terminal adapter say for use with another codec Envoy Product Manual SECTION 7 CODEC LOOPBACK TROUBLESHOOTING The Comrex Envoy coding algorithm eliminates redundancy in audio For this reason the Envoy cannot be subjected to traditional specifications of distortion and signal to noise ratio Most tests done with the codec should be by subjective listening between the original source material and codec processed audio Because of the algorithm s dynamic processing properties tests done with tones tend to prove little Unlike analog technology which might work but just be a little off digital technology tends to either work perfectly or not at all The trick is to isolate the source of the problem to either the telephone network or the equipment attached to it so you know where you can turn for a solution The Envoy provides some simple diagnostic functions to help you do this Codec and TA Loopback This test examines the codec portion of the Envoy independent of the built in TA or the digital circuit Audio must be fed into the unit through one of the audio inputs and you must be able to monitor an audio output either headphones or aux out Be certain to
36. ied these custom configurations for your line If in doubt about this choice contact the company that installed your ISDN line Refer to the next page to program the switch type into the Envoy 17 18 Comrex Corporation Before attaching the ISDN line power up the Envoy by plugging the external supply to A C and turning the switch on the rear panel of the Envoy Do not connect to the ISDN line before entering the switch type SPIDs and LDNs After a few seconds the status display will appear Don t be concerned with the Link Down message at this point Press menu on the status display to access the main menu Press conric to select the configuration menu Press NETWORK INFO for the network configuration menu Press swircu to enter the switch type menu Then select the switch type The Envoy will store your selection Press ger until you return to the network configuration menu Menu O Dial Redial Status Switch NI I Data Rate I28K Link Down Place a Call Configure Test Exit Dial Options Network Info More Exit SPIDS LDNS Switch Exit Network Config ATT SESS DMSIOO Type NAT ISDN Exit Switch A ft ft ft Selection Stored 4000 4488 4000 4488 4480 bab C Envoy Product Manual ENTERING THE SPIDs You will now program the exact Service Profile ID Number that the telephone company gave you for each channel of your ISDN line This number is used to handshake between
37. including public emergency numbers
38. iplexing standard called BONDING This allows for a transmis sion rate of 112 128 kb s on ISDN For more information on this subject see the Inverse Multiplexing section on page 48 This is the brain of the Envoy It communicates with the codec and TA sets them to the correct modes and provides the user interface for configuring and dialing the TA It also provides the ancillary data function and allows you to communicate to the TA via computer A substantial portion of the functions and features of the Envoy is software driven which will allow upgrades to these units by a simple exchange of EPROMS We will keep our customers apprised of software updates and make these available at no charge In order to assure that we will be able to contact you please be sure to return the warranty card with complete address and contact information Comrex Corporation SECTION 2 In this sample display the Envoy is set to dial at 128 kb s for 15 kHz audio The switch type is National ISDN 1 The OK in the lower left hand corner shows that the initial handshake with the line was successful Envoy MENU SELECTION TREE Status Switch NI I Data Rate I28K OK Menu Place a Call Key in number now Configure Dial Options Data Rate Prgrm Qdial Special Network Info SPIDS LDNS Switch More Audio in out Anc Data Profiles Test Codec Loopback Active TA Loopback Active QDial Qdial 01 20 Redial Dialing 56Kb s 4Kb s 11
39. is an RJ 11C If requested this information must be provided to the telephone company If the Comrex Envoy caused harm to the telephone network the telephone company will notify you in advance that temporary discontinuance ofthe service may be required But if advance notice is not practical the telephone company will notify the customer as soon as possible Also you will be advised of your rights to file a complaint with the FCC if you believe it is necessary The telephone company may make changes in its facilities equipment operation or procedures that could affect the operations of the equipment If this happens the telephone company will provide advance notice in order for you to make the necessary modifications in order to maintain uninterrupted service If trouble is experiences with the Envoy please contact Comrex Corporation at the address below for repair and warranty information If the trouble is causing harm to the telephone network the telephone company may request that you remove the equipment from the network until the problem is resolved Comrex Corporation 19 Pine Road Devens MA 01434 978 784 1776 The Comrex Envoy can only be used on ISDN lines providing a U interface and only one such device can be connected to a each line It cannot be used on conventional analog telephone lines of any kind including public coin service or party lines It also cannot be used to place calls to analog telephone equip ment
40. ld Ground Inner core 5V EIA 530 Data in out DTE Ancillary Data in out DCE Pin 1 Shield Pin 2 RX Data Pin 2 TX Data A Pin 3 TX Data Pin 3 RX Data A Pin 4 DTR unused Pin 7 GND Pin 5 GND Pin 9 RX CIk B Pin 6 DSR always valid Pin 12 TX CIk B Pin 7 RTS unused Pin 14 TX Data B Pin 8 CTS Goes valid on ready Pin 15 TX Clk A Pin 9 RI unused Pin 16 Rx Data B Pin 17 RX Clk A Pin 18 STL Mode trigger Pin 20 DTRA Pin 23 DTR B Pin 24 DTR RS232 53 54 Comrex Corporation APPENDIX A Asout Mix Minus Even the simplest remotes are a two way process The remote site must send its audio to the studio and receive a return feed to monitor the programming This return feed may be done over a radio station s regular transmitter with an AM or FM radio at the remote a special radio link or a telephone circuit This feed may just go to headphones at the remote and it may also be put on speakers for the local audience The problem comes when there is a time delay in getting audio to and or from the studio In this case the remote talent hears a delayed version of their voice in the headphones and may find this very distracting Even a remote done with simple equipment or a frequency extender on plain phone lines may have this problem on a long distance call All remotes using ISDN Switched 56 and POTS codecs will have delays each way as signals are processed from analog to digital compressed uncompressed and co
41. lem Check that you are plugged into the correct jack and that your telephone cord is OK Envoy Product Manual UsinG LONG DISTANCE ACCESS CODES If the display stops at an intermediate point unplug the line and check the numbers you have entered particularly the SPIDs You may have transposed some digits or made another mistake Focus on SPID 1 if the message stops at Getting TEI 1 or TEI 1 Found and on SPID 2 if it stops at Getting TEI 2 or TEI 2 Found Also be sure that you have correctly chosen the switch type Plug the line back into the unit and see if the problem is solved Still can t get the OK Assuming you haven t made a typo go ahead check those SPIDs again the telephone company may have given you incorrect information You may save some time by simply calling them and asking for it over the phone Otherwise here are some tips that may help you out e New ISDN lines are usually installed with SPIDs consisting ofthe area code local number and 0101 at the end The correct switch type for these lines is NI 1 It may be worth trying this combination e NI 1 is the proper choice for most new ISDN installations e There is a flavor of ISDN provisioning called SESS custom point to point that may not require SPIDs or LDNS If you think that is possible in your case try removing them and selecting 5ESS for the switch type Do note however that you may sometimes get a false OK when no
42. most other manufacturers G 722 ISDN codecs Automatically rate adapts to answer ISDN calls at 56 64 112 or 128 kb s Two contact closures one upon connection and one for triggering STL Backup Mode Ancillary data channel of 4800 baud allows a user to pass data between two computers great for call screening or delivering sports scores Ability to store 20 telephone numbers and last number dialed in nonvolatile memory 6mS coding delay allows seamless two way communication Four channel microphone mixer 2 channels mic line selectable Three headphone outputs adjustable mix of send receive audio Balanced line level audio out adjustable mix of send receive audio Input and output kill buttons Spotter producer input WHAT COMES WITH The following items are shipped with a new Envoy AN Envoy 1 Comrex Envoy ISDN codec 1 A C power module with A C cord 1 RJ11C modular telephone cord 1 Operating manual 1 Warranty card Please fill out and return Envoy Product Manual ABOUT THE ALGORITHM TERMINAL ADAPTER COMMAND PROCESSOR UPGRADES Codec is an acronym for Coder Decoder We define this as the part of the Envoy which takes in an analog audio signal converts it to a digital bit stream and performs operations on this bit stream to remove redundant information This operation is known as Digital Audio Compression The codec section also takes an incoming previously compress
43. mrex Corporation 28 ISDN LINE PROFILES Dial Options Network Info More Exit Audio in out Anc Data Profiles Exit 1 Anc Data off Anc Data on Exit 4000 4400 4404 For some users who carry their Envoy between different ISDN equipped locations it can become difficult and confusing to reprogram all the necessary information about the ISDN line into the Envoy each time it is moved The Envoy eases this task by allowing you to create nine profiles for ISDN lines which simply need to be loaded at each location Begin by setting all the Envoy parameters SPIDs LDNs switch type data rate and ancillary data for a particular venue pages 17 23 amp 27 28 Make sure that this information is entered correctly before storing the profile Then select MENU from the status display followed by conricure from the main menu In the config menu choose more Next select proHzEs for the profiles menu To store the profile press srork and choose a profile index number 1 9 The Envoy will automatically store all of the preset parameters To load the stored profile follow the above instructions to reach the profiles menu Once in the profiles menu select zoap and then the appropriate profile index number 1 9 The Envoy will automatically load all of the preset parameters Envoy Product Manual MENUS FOR LOADING AND STORING ISDN LINE Status PROFILES Switch NI I Data Rate I28K OK Place a Call Con
44. n menu Now press 7zs7 Select either loopback test If you have chosen the codec loopback test the rzapy light next to the display should now come on if you have chosen the TA loopack test the Spam and cp lights next to the display should now come on Now turn up the channel 1 knob farthest column on the left labeled RETURN until you hear the audio clearly When finished press zxrr until you return to the status display You have now set the correct headphone level for the audio which will come to you from the other end of the link To adust the listening level of the local audio turn the headphone control lableled Lo CAL until you get a comfortable listening level while audio is being fed into the Envoy Your headphone adjustment is complete Feel free to adjust zocaz and RETURN after a connection is made to achieve the right balance and overall level Headphones 2 and 3 are adjusted the same way In some situations you may wish to hear only zocaz or only rReTURN audio in a particular headphone Simply turn the unwanted audio control for that headphone all the way down Note Loopback tests and their functions beyond setting the headphone levels are explained on pages 35 37 Envoy Product Manual ABOUT UNBALANCED CONNECTIONS Auxiliary Output 4 There is one line level audio output on the Envoy labeled aux our Like the headphone outputs this is an adjustable mix of zo CAL and RETURN audio but it is at a balanced line level on
45. nd in voices At 112 or 128 kb s the Envoy carries through 15 kHz audio providing full FM radio qual ity bandwidth for voice and music There is little perceivable difference between 56 and 64 kb s as well as 112 and 128 kb s The 56 and 112 kb s rates are provided for compatibility with ISDN lines which do not provide clear channel 64 kb s transmission and also to interwork with Switched 56 systems If you are using ISDN on both ends of your system you should attempt to connect first at 64 or 128 kb s and if you experience problems try backing down to 56 or 112 kb s To select your data rate press menu on the status display to access the main menu Press conric to select the configuration menu Select paz oprrons for the dialer configuration menu Press DATA RATE to enter the data rate menu Select the data rate you want to use The Envoy will store your choice and retain it in memory even if the unit is powered off Return to the status display by pressing EXIT Under most circumstances two Envoys or an Envoy and a Nexus which are set to different data rates will negotiate down to the setting of the lowest unit however this feature is dependent on the network and may not always work This allows for a unit which accepts incoming calls to be set to 128 kb s and automatically adjust to take calls from units set to lower rates Status Switch NI I Data Rate I28K OK Envoy Product Manual SELECTING THE DATA RATE Plac
46. nsport over digital networks At the transmit end the information is encoded and it is decoded at the receive end Simple Well not so simple As with most things in the world if everyone created their own method of doing things nothing would work together Something as simple as the standardization of power plugs means that we don t think twice about buying appliances or electronic components But we do think twice about what form our videotape is in VHS or BETA But at least it is a small field from which to choose The same thing is happening with the compression algorithms used to encode and decode audio signals International standards bodies have formed to create standards There are a different standards available like VHS and BETA and it is up to you to select which one you will implement It is also up to you to insure that the vendor you select is implementing the standard with no changes that can mean your equipment will not work with other manufacturers and you will be boxed into a corner The international standard known as CCITT G 722 specifies the algorithm that codecs use to convert analog to digital signals and vice versa The Envoy fol lows this standard very carefully and can communicate with G 722 codecs from other manufacturers The Envoy also incorporates a proprietary upgrade of G 722 which automatically doubles the audio bandwidth to 15 kHz when the codec sees a transmission rate of 112 or 128 kb s The En
47. nus are disabled For this reason you will want to make sure all settings are correct before you enter any special mode 31 32 Comrex Corporation STI Backup MODE This mode allows the Envoy to automatically dial the number stored in QDial 01 Select s7 mope from the special modes menu once all your Envoy options kb s ancillary data etc have been set The Envoy will dial Qdial 01 when the STL mini jack on the rear panel of the Envoy is closed It will disconnect when the contact closure is opened or STL Backup mode is exited If the Envoy should lose power while in STL Backup it will return to this mode when power is reapplied STL Backup mode is also useful in providing fail safe remote operation Simply close the STL mini jack on the rear panel of the Envoy When ready to place a call enter STL Backup mode having preset all the Envoy param eters The Envoy will immediately dial Qdial 01 and connect If at any point the connection should be lost the Envoy will detect this and immediately redial the number When the call is to be disconnected exit STL Backup mode The contact closure will have no effect on operation other than STL Backup mode ft STL Mode Special Ldm Mode Modes Ext DCE Exit STL Mode Active Exit AAA 4440 Envoy Product Manual LDM MODE Special Modes The Envoy has the ability to operate as a Limited Distance Modem LDM on a dry pair or plain old copper wire
48. nverted back to analog audio Some digital compression schemes such as G 722 result in shorter delay times but there will still be a reverb effect in headphones at the remote site if their audio is sent back from the studio In any of these cases it may not be possible for the remote people to listen to an off air or program channel feed The solution is mix minus A mix minus feed has a mix of all of the program ming on the radio station or network minus the audio from the remote In other words the station or network doesn t send the remote audio back to the remote At the remote end this mix minus feed is converted back to an air monitor by mixing in the local audio from the remote This is easily done on the Envoy with the LOCAL volume control For radio stations in addition to fixing the time delay problem using a mix mi nus feed has two other advantages First if the station uses a 6 7 second delay to allow editing of phone calls pre delay audio can be sent to the remote site Second if there is a PA system at the remote they will be able to run the speaker levels higher with the mix minus audio This is because the remote microphone audio is not running through the station s audio processing and the levels stay under the control of the remote operator The simplest way to do one mix minus feed in a typical radio studio is to use the Audition or second program channel On many audio consoles each fader s outpu
49. ome in chunks of 56 or 64 kb s These chunks have very little to do with each other normally They may be routed differently throughout the telephone network and incur substantially different transmission path de lay Even the two B channels of a Basic Rate Interface ISDN installation offer no guarantee that both calls will be routed along the same path On a North American coast to coast linkup for example the first B channel connection may be routed via Texas and the second via Michigan The IMUX must be able to measure the time delay between the two digital chan nels and delay the fastest so that it arrives synchronously with the slowest This procedure is called aggregation and is performed differently with different IMUX protocols The Envoy Terminal Adapter uses an IMUX protocol called BONDING the most widely used IMUX standard in North America to send 15 kHz on a BRI ISDN line 128 kbps d Envoy Product Manual ABOUT ANCILLARY DATA The Envoy provides an ancillary data channel which allows the user to send low speed data along the same digital telephone channel used for the Envoy audio The vital information you need to know is that this channel has the following parameters 4800 Baud 8 bits no parity 1 stop bit Now we will describe a few concepts The Envoy ancillary data channel is asynchronous This is the most common format for information exchange between computers An asynchronous data link
50. opriate indication is achieved on the VU meter These knobs determine the level of the audio on each headphone that is re ceived from the other end of the link Adjust these knobs until a comfortable listening level is achieved If you do not wish to hear any return audio on any particular headphone turn that control all the way down The headphone control knobs are color coded to coincide with the input level controls These knobs determine the level of the audio on each headphone that is gen erated locally within the Envoy This includes all the mics and other sources plugged into the Envoy as well as the aux input if it is set up as a producer or spotter feed Adjust this knob until a comfortable listening level is achieved on the headphones If you do not wish to hear any local audio on any particu lar headphone turn that control all the way down The headphone control knobs are color coded to coincide with the input level controls Note The headphones can be set up two different ways in the menu system The first option is to hear the same mix of local and return audio in both sides of each headphone The second option allows for a split feed where the local audio is heard in the left side of the headphones only and the return audio is only heard in the right side See page 14 to configure These are 3 conductor 1 4 inch headphone jacks suitable for most stereo headphones This is a signal from the digital audio decoder whic
51. rminal adapter and the codec portions of the Envoy together Again audio must be fed into the unit through one of the audio inputs and you must be able to monitor an audio output either headphones or aux out Be certain to turn the LOCAL PROGRAM volume control all the way down so that you are sure you are monitoring the codec return audio only Power must be connected to the Envoy and it needs to be turned on You do not need to be connected to an ISDN line or other type of digital service This test cannot be run while a call is placed Select menu on the status display Then press rer in the main menu Once in the loopback options menu select 74 This will send your audio through the encoder to the TA and back through the decoder without going on to the net work Press zxr at any time to leave TA Loopback Envoy Product Manual ExPECTED RESULTS IN TA LOOPBACK TEST fh Status Menu Q Dial Switch NI I Redial Data Rate I28K Link Down Place a Call Configure Test Exit f ft Loopback Options Loopback Active Exit 4000 4400 4400 4404 You will hear the same audio in your headphones that is being fed into the Envoy The READY and cp lights should be on Note there may be a few seconds of noise before your audio is beard Also there will be a noticeable delay in the audio returned to the decoder from the TA This delay is a function of the TA loopback test and does not reflect actual coding delay in progr
52. s successful you have sent data down the cable to the Envoy into the encoder looped through to the decoder and back to your computer screen If not successful try the following 1 Type AT Enter Ifyou get a response OK then you are probably talking to a modem inside your computer configured for the chosen comm setting Try a different configuration 2 Try adifferent comm port Sometimes these ports burn out if connected wrong previously 3 Remove any adapters dongles or other connectors on the port 4 Make sure you are using a straight through 9 pin to 9 pin cable Do not use a null modem cable 51 52 Comrex Corporation Envoy SPECIFICATIONS ISDN CONNECTION Connections Audio In 3 pin XLR female 4 Audio Out 3 pin XLR male 1 Headphone Out 1 4 stereo phone jacks 3 Tel Line amp Tel Set 6 pin RJ11C Modular Jacks 2 Contact Closures Ready amp STL 1 8 2 conductor mini jacks 2 Accessory Port 9 pin D type connector 1 Levels Audio input impedance 10K ohms Mic input levels 85 to 40 dBu Line input levels 10 to 10 dBu Audio output impedance 100 ohms Line level out 12 dBu max Headphone out 5 watt Ancillary Data RS232 EIA 530 Data In Out RS422 Audio Bandwidih 56 64 kb s 20 Hz 7 5 kHz 112 128 kb s 20 Hz 15 kHz Power External supply 5V 4 Amp 100 to 240 VAC 50 60 Hz Power Connection 2 1mm i d 5 5mm o d coaxial Size 13 Wx9
53. simply provides a pipe which passes bits back and forth between the devices What you do with this data is dependent completely on the comput ers and software used in the connection It is the nature of asynchronous data that we define a baud rate This is the rate at which individual bits run along the asynchronous link In some asynchronous systems however a continuous stream of data at the specified baud rate will overload the system This is because the baud rate specifies only the speed on the pipe feeding into the system Further down the pipe may narrow and less throughput is possible Asynchronous communication allows flow control where the sending device will be triggered by the network when enough capacity is available to send more information In the Envoy the pipe has the same throughput all the way across and flow control is not necessary Flow control works because asynchronous links do not need to send infor mation at all times When there are no characters for a computer to send a modem for example the asynchronous link is idle When the computer has information to send it will usually format this information into one or more bytes attach a start and stop bit so the receiving system knows where the byte begins and ends send it off and again make the line idle In the most common application for ancillary data two terminals with operators sending text characters back and forth the asynchronous link is a
54. t ing of seven or eight characters The receiving codec is able to decode and decompress data intelligibly because it has identified the beginning and end of each word it receives This process of identifying and aligning with the correct word order is called synchronization The Envoy uses a self synchronizing technique which allows the encoder to use the entire channel for audio data With no overhead for synchronization data the decoder can determine the sync position by performing an algo rithm on the raw incoming data It takes about one second for the decoder to find sync and begin decoding data The reapy light on the front panel is an indication that the decoder is in sync Every half second the Envoy rechecks to make sure that it is still in sync If the network causes an error that makes the data stream line up differently the codec can determine this and resync within one second Remember because the Envoy is fully duplex it is simultaneously encoding compressing outgoing information and decoding decompressing incoming information 47 48 Comrex Corporation NVERSE MULTIPLEXING Inverse Multiplexing or IMUXing for short sounds complicated but is actually quite simple It means combining two or more lower data rate channels into one higher data rate channel It is an extremely important concept when working on digital phone lines like Switched 56 and ISDN as digital transmission chan nels on these services c
55. t may be sent to both Program and Audition If your board will allow those feeds simultaneously just set all of the modules to Program and Audition with the exception of the one carrying the remote audio Set that one to Program only The Audition channel will then be a mix of everything on the console except the remote That will be your mix minus and it should be sent to the remote site One caution make sure that audio is being sent to and from any telephone modules you may have in the console They may have been designed to work with only one channel at a time either Program or Audition but not both If so you will have to check with your tech guy or the board manufacturer for advice If you use multiple audio codecs you should Envoy Product Manual Tm Using Mr MInus AND I Stur HEAR AN Echo investigate the Comrex Mix Minus Bridge This will allow you to expand one Program Audition setup to handle five codecs or other remote audio devices It also provides IFB talkback to remote sites A Audition Output AUD IO Out Codec Output all audio except codec d CODEC u remote audio TO Remote FROM Remote Main program feed leaving studio PGM AUD OUT OUT H E BEOO Pm BHOO H m BEOO H BEOO m gt HOO E HOO MIC cD REM NET H E BEOO E m BEOO H BEOO If you are using an
56. testing Circuit Switched Data CSD Bearer Channels Any Number of CSD calls 2 if 2B D 1 if 1B D Terminal Type Type A Turn the following features OFF Packet Mode Data Multiline Hunt Groups Multiple Call Appearances Electronic Key Telephone Sets EKTS Shared Dictionary Numbers Accept Special Type of Number Intercom Groups Network Resource Selector Modem Pools Message Waiting Hunting InterLata Competition Envoy Product Manual DMS 100 NORTHERN TELECOM SWITCH CHECKLIST FOR ALL SWITCH TYPES When accessing a DMS100 switch you are required to have two phone num bers and two SPIDs Therefore all service is Point to Multipoint Request an ISDN Basic Rate Interface BRI with Line type Basic Rate Functional Electronic Key Telephone Sets EKTS No Call Appearance Handling CACH No Non initializing Terminal No Packet Switched Data Service No TEI Dynamic Bearer Service Circuit Switched Voice and Data permitted on any B Channel Packet mode data not permitted After you have placed your order make sure that the phone company provides you with the following information for programming the Envoy ISDN Switch Type ISDN phone number s or LDN SPIDs with prefixes and suffixes if your switch type needs SPIDs 45 46 Comrex Corporation Section 10 G 722 ALGORITHM THEORY OF OPERATION TECHNICAL DETAILS The codec is a system that encodes and decodes audio signals for tra
57. the telephone company and the Envoy Press sems while in the network configuration menu to begin entering the SPIDs After SPID 1 is programmed press ox The SPID 2 menu will appear After programming SPID 2 press ox to return to the network configuration menu IfSPIDs were previously programmed into your Envoy they will appear If they are correct press ox until you return to the network configuration menu If you wish to change a previously programmed SPID or if you make a mistake while entering the number press Back space until the number is cleared and then enter the correct number ft Network Config Enter SPID OK Back Space Selection Stored Cancel 4000 4404 Enter SPID 2 OK Back Space Selection Stored Cancel AAA 4404 4444 20 Comrex Corporation ENTERING THE LDNs Note Some ISDN lines use two SPIDs some use one and some use none at all Often your SPID resembles your phone number plus area code with leading or trailing digits If your line was configured for two SPIDs you must enter the appropriate numbers exactly as they have been given to you by the phone company into the SPID 1 and SPID 2 menus If your line has only one SPID program that number into both SPID 1 and SPID 2 menus If you have ordered service on only one B channel 1B D enter the SPID number into SPID 1 and leave SPID 2 blank Finally if your line has no SPIDs verify that there are no numbers programmed
58. thout special interface equipment Once a call is placed on an ISDN line it is treated by the telephone company very much the same way a voice call is Most of the technology of ISDN lies in the link between the phone company and the customer The single ISDN phone line has the capability of carrying two independent telephone chan nels These are called B channels and an ISDN user may place a call on either one or both B channels simultaneously The device used to place and answer calls on an ISDN line is called a terminal adapter When used for data each B channel of an ISDN has the capacity of 64 000 bits per second 64 kb s The two B channels may be dialed to the same location and their capabilities summed together for a total throughput of 128 kb s Some ISDN networks use a small piece of this data so they allow the user a little less throughput The user may have 7 8 of the B channel or 56 kb s Two B channels may then be summed to 112 kb s Envoy Product Manual SECTION 9 ISDN SERVICE ORDER INFORMATION ORDERING ISDN The Envoy ISDN Codec includes both NT1 and Terminal Adapter functionality and supports data rates up to 128 kb s Ifthe telephone company handling your ISDN service order uses the Bellcore National ISDN Capability Package designations simply ask for Capability Package M or Generic Data M For telephone companies requiring the full details request an ISDN
59. tput XLR connect pins 1 and 3 together and tie this to ground on your unbalanced device Tie pin 2 on the Envoy XLR to audio on the unbalanced device 15 16 Comrex Corporation BEFORE YOU START The following information has to be programmed into the Envoy before it is connected to an ISDN line and each time it is moved toa new line Switch type SPID numbers Service Profile IDentifiers Local dialing numbers LDNs This data is provided by the telephone company and it is unique to the specific ISDN line to which you are connecting Do not let your ISDN installer leave without being certain that you have the correct information in hand Otherwise it can result in the Envoy not working at all or partially working and can re quire time consuming troubleshooting Incorrect phone company information is the number one source of difficulty when configuring ISDN equipment The second is incorrectly installed phone lines which we deal with in the Look for the Big OK section on pages 38 39 The switch type SPID and local phone numbers need to be programmed into the Envoy before it is attached to the ISDN line If you reenter any of these values once the Envoy has shaken hands with the line disconnect the Envoy from the line temporarily or power it down momentarily in order to initiate a new handshake Any information entered into the Envoy will be saved if it is turned off or loses power so you will not nee
60. turn the zocaz PROGRAM volume control all the way down so that you are sure you are monitoring the codec return audio only Power must be connected to the Envoy and it needs to be turned on You do not need to be connected to an ISDN line or other type of digital service This test cannot be run while a call is placed Select menu on the status display Then press rer in the main menu Once in the loopback options menu select copgc This activates two things It puts the local clock into use to drive the signal and it connects the encode and decode channels Press zxr at any time to leave Codec Loopback Status Menu O Dial Switch NI I b Data Rate I28K Redial Link Down bob Place a Call Configure Test Exit AAA 4 35 36 Comrex Corporation EXPECTED RESULTS IN CODEC LOOPBACK TEST TA LOOPBACK ft Loopback Options Loopback Active Exit 9008 4404 You will hear the same audio in your headphone that is being fed into the En voy The reapy light should be on Note There may be a few seconds of noise before your audio is heard If you do not hear audio or it is distorted e Check your connections e Make sure the VU meter peaks occasionally over the 0 mark which is the yellow LED on the meter e Insure that the mic line switch is in the correct position If there is still a problem please contact Comrex Tech Support to arrange for repair of the Envoy This function tests the te
61. ty and fitness for a particular purpose which are hereby expressly disclaimed In no event shall Comrex Corporation have any liability for in direct consequential or punitive damages resulting from the use of this product Copyright Notice The Comrex proprietary code and licensed third party proprietary code residing in and otherwise associated with this product are protected by copyright law and international treaties Unauthorized reproduction or distribution of this product or any portion of it may result in civil and criminal sanctions and will be prosecuted to the fullest extent of the law US Government Restricted Rights Use duplication or disclosure by the US Gov ernment is subject to restrictions set forth in subparagraph c 1 ii of the Rights in Technical Data and Computer Software clause at DFARS 48 CFR 252 227 7013 or subparagraphs c 1 and 2 of the Commercial Computer Software Restricted Rights clause at FAR 48 CFR 52 227 19 as applicable Comrex Corporation SECTION 1 NTRODUCTION Envoy FEATURES The Comrex Envoy is an audio transmission device for ISDN digital circuits The Envoy includes codec Terminal Adapter NT 1 and mixer in a rugged lightweight easy to use package Additional features include Full duplex 7 5 KHz or 15 kHz audio Easy to use dialing and configuring interface Available in portable chassis Compatible with the Comrex Nexus DXR 1 DXP1 and Matrix ISDN codecs as well as
62. voy will automatically adjust to the transmission speed and it is therefore not necessary to make any adjustments to the codec to change from standard G 722 to the upgraded version The Envoy performs a digital algorithm in real time on sampled digital input audio The unit is based on a high speed computer chip known as a digital signal processor DSP The idea behind the codec and any other DSP based device is to perform functions on analog signals which have been divided into samples taken at discrete times These samples are then quantized assigned a fixed value and fed as a stream of binary numbers into the DSP The basic assumption of the codec is that digitized audio contains more informa tion than is needed to reproduce it in analog form By eliminating this redundant information more audio information may be stored or transmitted As mentioned before the input to the DSP portion of the codec is a series of discrete time samples Each portion of the codec link transmitter and receiver contains a computer program which can predict the next sample based on previ ous values processed This function is performed identically in the transmitter and receiver Envoy Product Manual SYNCHRONIZATION The difference between the transmitter and receiver is that only the transmit ter knows the true value of the next discrete time sample Since it already possesses an approximation of this value it can calculate the difference b
63. your telephone company has at the other end of your ISDN line Regardless of the make or model of their switch if they are using the National ISDN 1 or 2 software the correct choice would be NI 1 Also note that if the SPID numbers end in 0101 you can assume that NI 1 would be the switch type LDNs The local dialing numbers are almost always just the 7 digit local tele phone numbers without the area code or the extra digits found in the SPIDs Once you have this information unplug the ISDN line from the Envoy and program the unit according to the instructions pages 17 21 With all of the numbers and choices stored go back to the top menu and plug the line back in You should now see a series of messages on the LCD screen some may be skipped ending in OK Allow a minute or so for the process to complete Link Message Description Link Down No activity has been detected on the ISDN line ISDN Found Layer 1 Physical handshake accomplished with line Getting TEI 1 Terminal Endpoint Identifier 1 is being retrieved TEI 1 Found Terminal Endpoint Identifier 1 is OK SPID 1 OK Service Profile ID 1 is OK Getting TEI 2 Terminal Endpoint Identifier 2 is being retrieved TEI 2 Found Terminal Endpoint Identifier 2 is OK SPID 2 OK Service Profile ID 2 is OK OK SPIDs are OK handshaking is completed If the unit stops at Link Down there is a basic communication problem with the ISDN line possibly due to a physical wiring prob

Download Pdf Manuals

Related Search

Related Contents

Télécharger la notice  istruzioni d uso e manutenzione use and maintenance instructions  (0163-044-G) TABS 4 in 1.qxd  OnDeck 2011年6月9日号    Exacompta 804172 photo album  陸 上 自 衛 隊 仕 様 書  FR INFORMATIONS IMPORTANTES SUR LE PRODUIT  PDFをダウンロード    

Copyright © All rights reserved. Failed to retrieve file