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OPERA TING AND SERVICE MANUAL WILLARD MODELS 87XX1

1. TES DEE MATERIAL R9 1K p RII 2K 5V loo 084 I5 0 8L0 2 1000 185 00 055 gt y C8 T 68 20 R53 500 R22 14 Q O 1 o gt BRAKE 2 5 596 MOTOR 09 CC 010 AT x 5 2 r 18 T 22 10v 4 7 10V 16 G 234 R31 LEFT ARM 33K 2 SENSOR 4 S wy 5y 30K 3 t 014 E m gt LEFT LIMIT TPI7 CRIO6 SENSOR EN RIGHT REEL sn gt 14V MOTCR OMNEM CS 00 544 847 4 7 10 V R43 12 RIGHT ARM 33K d POSITION SENSOR TP25 PT 00 043 RIGHT LIMIT R48 Ss SENSOR 199 t 6 8 20V 2 TP4 TP24 9 5 14V uM E E du Se oe 2145 J2 20 UE 4 WRITE ENABLE 9 WRT PWR C4 100 12V 4 WRT PWR TO DATA 8147 BOARD 4 7K INTERLOCK I T ES Qj m c m 100 12 6 TP27 Vs L s CRHO e or gt 2 5V 00 046 MEL TP 44 LOAD CRIO9 J 16 4 00 045 zh DSEE VERSION TABLE FOR USE 5 ALL DIODES ARE 00 021 4 ALL CAPACITANCE VALUES IN MICROFARADS 3 ALL RESISTORS ARE 1 4 WATT 596 VALUES IN OHMS FOR ASSEMBLY DRAWINGS SEE 20 157 4 TITLE 2 ALL PNP TRANSISTORS ARE 00 020 20 118 TRANSISTOR MOUNTED ON HEAT SINK 1 ALL NPN TRANSISTORS ARE
2. REF DES 20 355 20 356 _ ee Bee P eer SE DATA BOARD A DWG NO O 558 5V 225 IR5 IRT i 220 1 62 K 1102 1 lt IWDP 330 13 12 34 1 8 02 10 N lt Qo m ICRIICR2 JI02 M IWDO J102 Il z 10 282 330 N 2192 gt gt 392 J102 12 a 330 5V 481 220 2 diez pr gt n wD2 2102 13 330 12 SRI 220 MN 102 5 J 0 IwD3 5R2 Hurl J102 14 330 12 5 V ERI 220 5 6 el J102 5 E 4 END J102 15 330 D 220 J102 T IwD 330 13 12 5 7R2 J 102 16 5V amp C CES 88 s gt 2102 LWD6 882 ne JI02 17 4 a 830 me Jon 220 2102 LW J102 18 330 a ICR 4 14 5V 5V 95 Q2 42053 220 00 019 00 019 3 3 UF R14 RI2 15 9 I74K 470 8 HIZ 5V R IP5 u35 6 828 IWDS n2 SR 20K 50K R 4102 1 u37 6 5 v R29 R27 TP2 CR4 4 99K 4 99K C34 U38 8 8 es CR5 1 4 w 17 517 MOTION is JI 6 C7 C6 5V d 9 6 U32 6 2 15 2 U33 8 U2 ES 2 6 j id Ee 055 6 5 2 JIO2 C U35 8 R6 RIO IWARS 330 22 yp TP14 TPI3 102
3. eser ies ic ae SCHEMATIC CONTROL ELECTRONICS ca UNE T Begi SH 2 OF 2
4. TENSION ARM SENSORS AND LIMIT SENSORS WRITE ENABLE SWITCH BOT amp EOT SENSORS MAGNETIC HEAD Figure 4 1 Organization Of The Transport AC POWER when each of the appropriate control switches is depressed Figure 4 2 gives the load sequence waveforms 42 1 1 Depress POWER Switch Depressing the POWER switch applies AC line voltage to the power supplies Power supply voltages are applied to all circuitry but the inter lock relay is not energized Therefore the servo amplifiers are not con nected to the motors Consequently at this point no tape motion is possible 4 2 1 2 Depress LOAD Switch The First Time The normally open contact from the load switch is connected to the cathode of CR108 this condition the base of Q109 is held at approxi mately 5V through R147 and K1 D Q110 is held off and relay is not energized When the LOAD switch is depressed the base of Q109 is momen tarily held at about one diode drop above ground Q110 is turned on and relay and the brake solenoids are energized Energizing K1 A K1 B and K1 C causes the motors to be connected to the servo amplifiers The tape is then given tension and the arms move into position K1 D provides the interlock signal and write power 4 2 1 2 1 If a write enable ring has been inserted in the supply reel the write enable switch will be closed Thus when K1 D closes 5V power is applied through R146 to the base of tra
5. 04 99 910 0106 0107 Q109 Q5 011 Q15 0108 96 913 921 Q17 Q20 Q110 R1 R118 R121 R3 R5 R13 R14 R15 R24 R4 R6 R27 R28 R40 R41 R48 R49 R50 R7 R9 R10 R12 R52 R120 R123 R149 R8 11 R18 R29 R16 R33 R17 R35 R42 R19 R20 00 136 100PF 00 138 100MF 00 146 3 00 139 22MF 00 147 6 8MF 00 140 047MF 00 145 22MF 00 145 4 7MF 00 136 750PF 00 189 005 MF 00 140 022 00 140 00 140 001 00 145 10 00 048 00 021 00 047 00 045 00 046 00 034 _ 00 043 00 044 00 020 00 019 00 041 00 042 00 164 00 049 00 040 00 024 5 00 022 10 00 026 47 00 026 100 00 026 1K 00 026 2K 00 026 3 3K 00 026 330K 00 024 100K 00 022 100K PARTS LIST FOR ASSEMBLY CONTROL 20 163L Continued REFERENCE DESIGNATION PART NUMBER R21 R124 00 024 1K R22 R23 00 022 40 2K R25 00 022 5 49K R26 00 026 270K R30 00 026 6 8K R32 00 026 100K R34 R38 R43 R46 R126 00 026 33K R31 00 026 12K R39 R47 00 026 180K R51 00 026 20K R53 00 023 500 R54 00 022 560 R55 00 022 1 62K R101 R102 R108 R127 R134 R139 R147 00 026 4 7K R103 R105 R107 R109 111 R113 R115 R117 R119 R122 R128 R130 R132 R135 R137 R140 R145 00 026 220 R104 106 R110 R114 129 R133 R136 R144 R146 00 026 330 R112 R116 R131 R138 R141 R52 00 026 1 5K R150 R151 00 026 2 2K R125 R142 00 026 6 2K Ul
6. 1 9CR1 1CR2 9CR2 1CR3 9CR3 and 1CR4 9CR4 are no longer required These diodes were protecting the read amplifier from write current transients Secondly the read threshold is no longer selected by external control During writing the high threshold is selected during reading but not writing the low threshold is selected This is accomplished by the connection of U4 pin 6 to U42 pin 9 4 16 SECTION V MAINTENANCE 5 1 INTRODUCTION This section contains information necessary to perform electrical and mechanical adjustments to the unit Drawings necessary for electrical adjustment or troubleshooting are contained in the Appendix 5 2 FUSE REPLACEMENT Two fuses are mounted on the unregulated power supply cover The line fuse is a 2 slow blow while the 14V fuse is rated at 6A An addi tional 6A fuse is used in the 18 Volt supply for 25108 models 5 3 TRANSPORT CLEANING Clean the transport in the following five areas the head and asso ciated guides the capstan the roller guides the take up hub and the tape cleaner These areas of the unit are to be cleaned with non abrasive line free cloth or cotton cleaning agent must be XYLENE an alternate isopropyl alcohol may be used 5 3 1 The following precautionary notes must be observed when cleaning 1 When cleaning head or head guides not use any rough abrasive cloth not use any cleaning agent other than XYLENE
7. 1820 9R20 1R24 9R24 1R21 9R21 01 U5 U6 U2 03 U4 031 012 016 017 921 022 030 032 033 035 037 1 38 U34 936 PART NUMBER 00 026 4 7K 00 026 12K 00 026 3 9K 00 026 100K 00 026 1 00 012 00 017 00 015 00 013 00 181 00 014 00 018 00 180 00 016 POWER FAIL RESTART OPTION WLI Part No 20 309 and 20 344 FOR WILLARD LABORATORIES TAPE TRANSPORTS THEORY OF OPERATION power fail restart option provides a safe means of restarting a WLI tape transport after power failure without the need of operator attendance Reference is made to the attached schematic 20 311 Figure 1 shows block diagram of the circuit LOAD VOLTAGE ON DELAY DETECTOR SERVO RESTART R LATCH 6 _ ON LINE L _ DELAY Figure 1 ON LINE PULSE GENERATOR The voltage detector monitors the servo voltage 14V 4 and the relay and brake solenoid supply 14VS TB2 1 After the 14V supply reaches a level ensuring proper servo operation the U1 A output goes to initiating a load operation 1150 CR5 and R7 provide gt for drop in servo voltage when relay actuates the servo motors After elapes of a time delay generated by C2 R3 a latch U1 B and U1 C is set provided the relay TP26 was actuated This in turn causes the output of U1 A to go to 5V thereby terminating the load operation A 12 la
8. SHIP SEPARATE SPARE PARTS LIST PART ITEM E 20 375 Tape Guide Assembly 20 141 Photo Sense Assembly 20 106 Position Sensor Assembly 20 111 Roller Guide Assembly 20 140 Capstan 20 131 Tape Cleaner Assembly 20 331 Door Assembly 20 194 Write Enable Switch 00 167 Belt Pulley Magnetic Head 00 001 9 Track Single Stack B wi E 00 007 9 Track Dual Stack R W E 00 008 7 Track Dual Stack R W E 00 009 7 Single Stack R W E Control Panel Assembly 00 101 Power Switch PB 00 102 Load Switch 00 103 Rewind Switch PB 00 104 On Line Switch PB 00 105 WRT EN Switch 00 106 HI DENS Switch PB 00 107 Forward Switch PB 00 108 Reverse Switch PB 00 109 Reset Switch PB 20 355 Assembly Data Replaces 20 160 20 341 Power Supply Assembly Electronic Control Assembly 20 333 For 7 Track Dual Density Model 875818 20 346 For 9 Track Model 890815 NOTE 20 333 and 20 346 differ in jumper installation only See schematic diagram 20 163 20 244 Magnetic Head and Tape Drive Assembly 7 Track Single Gap 20 247 Magnetic Head and Tape Drive Assembly 9 Track Dual Gap 20 309 PCB Assembly Power Fail Restart PART NUMBER CROSS REFERENCE WILLARD LABS MANUFAC TURER DESCRIPTION OR PART NUMBER OR EQUIVALENT PART NUMBER Capacitors Disc 00 136 Series 5GA 20 500V 00 189 Series TG 20 100V Capacitors Electrolytic 00 052 STM 21 15HC223 22000UF 15VDC 00 053 S
9. the FWDC goes false and the tape decelerates to a stop An inter record gap will occur be tween the LRCC and the first character of the next block This gap consists of the stop deceleration time the start acceleration time for the succeeding record and a time T determined by the interface This time T is the delay between the FWDC going true and the fivst WDS 4 5 2 4 If it is desired to separate files of information on tape a File Gap is used file gap is a special character recorded followed by an LRCC Figure 4 5 shows file mark recording for 9 and 7 track tems To record mark an FWDC is first given After the tape is up to speed a mark is written defined as follows a file mark for a 7 track system consists of a 1 in data bits 4 5 6 and 7 a file mark for a 9 track system consists of a 1 mark in bits 3 6 and 7 After the file mark is recorded an LRCC is written 4 character times later in the 7 track sys tem and 8 character times later in the 9 track system 4 5 3 Circuit Description The data electronics circuit description will be made with refer ence to Channel 1 Channels 2 through 9 are identical to number 1 Compo nent designation refer to schematic 20 355 20 182 for read after write ver Sion shown in the Appendix 4 5 3 1 Writing Writing is performed by switching ON transistor 1Q1 or 1Q2 thus allowing current to flow in one half or the other half of the center tapped head windin
10. 3 4 7 FORWARD 3 4 8 REVERSE 3 4 9 RESET 3 5 INTERFACE INPUTS Select SEL Forward Command FWDC Reverse Command REVC Rewind Command RWC Write Enable Command WEC Write Data Lines WDP WD0 7 for 9 Channel WDP WD2 7 for 7 Channel 7 Write Data Strobe WDS 8 Write Amplifier Reset WARS 9 Read Threshold RTH 1 1 02 Co C2 CO CO CO wo c Q cor OQ 5 10 Off Line 5 11 High Density Select HDS Optional 1 l I l I l i l l 1 I bo E F3 H H E 02 02 02 52 02 02 02 592 C9 C9 C29 C2 C29 CO CO pO DO DO 1 TABLE OF CONTENTS Continued SECTION 3 6 INTERFACE OUTPUTS 3 6 1 Ready RDYI 3 6 2 Read Data RDP RDO RD7 9 Channel RDP RD2 RD7 7 Channel Read Data Strobe RDS On Line OLI Load Point LDP 3 6 3 3 6 4 5 6 7 8 9 3 3 3 Rewinding RWD File Protect FPI High Density Indicator HDI 6 6 6 6 6 6 6 9 7 INTERFACE TIMING 4 THEORY OF OPERATION 1 INTRODUCTION CONTROL LOGIC 4 2 1 Bring To Load Point 4 2 2 Monitor Commands After Initial Loading Of Tape 4 2 3 Rewind Command 3 POWER SUPPLY 44 SERVO AMPLIFIERS AND TAPE STORAGE SYSTEM 4 4 1 Capstan Servo 4 4 2 Reel Servos 4 5 DATA ELECTRONICS 4 5 1 Introduction 4 5 2 Data Recording 4 5 3 Circuit Description 4 5 4 Dual Gap Option 4 4 2 1 INTR
11. 3 I4 6C 11 VJ Pi Cue 6CRIO E 5 6R 24 6CR9 LI D 6R 23 6CR7 604 C30 T 7 R21 6 5 7822 PORE 20 I4 7CR11 7C4 7 10 76 24 7CR9 Pi D 7R23 4 7067 704 ERTS ERZ 7 5 82 86 IC BR 20 2 8 11 486810 74 e 8CR9 XI D 8R 23 co E _ scR7 804 9 9R18 9 R 21 8 5 9822 9R 9620 219 49 810 5 22 9CR9 XI D 9R 23 9CR7 904 5 9 C16 GND UNLESS OTHERWISE SPECIFIED Y C 614 e 15 pe 2 ae 1 6 L 9 5V 2 66 3 6 d 4 R20 4 69 1 109 U35 6 6 CRI 7 6 9 2 9 6 V CR4 038 GND E Pi FINISH PART NUMBER OR DESCRIPTION MANUFACTURER OR MATERIAL PART OR MATERIAL SPEC 20 356 20 355 REF TNE TECHNICAL DATA AND THE DESIGNS DISCLOSID wi SERVICE CORP OR CONTAIN PROPRIETARY RIGHTS Of QIN SAE AND ARC NOT BE USED OR DISCLOSED TO OTHERS WITHOUT THE WRITTEN CONSENT Of PRODUCE OL ai 1 DIMENSIONS IN INCHES 2 SHARP EDGES 010 J MACHINED SURFACE ROUGHNESS 63 MICRO INCHES R M S 4 DIMENSIONS APPLY BEFORE PLATING 5 MACHINED SURFACES SHALL IN ALL PLANES 001 INCH DIAMETERS WITHIN 005 T I R 6 TOLERANCES 0 30 7 LINEAR TOLERANC
12. Strobe RDS This is a pulse of minimum width 2US used to sample the read data lines The trailing edge of the pulse should be used for sampling The time between RDS pulses will vary considerably because of skew bit crowd ing and speed variations 3 6 4 On Line OLI This is a level which is true when transport is under remote control When it is false the transport is under local control 3 6 5 Load Point LDP This is a level which is true when the BOT tab is under the photo sensor The signal goes false after the tab leaves the photosensor area 3 6 6 End Of Tape This is a level which when true indicates that the EOT tab 18 under the photosensor 3 6 7 Rewinding RWD This is a level which is true when the tape is rewinding or in the load sequence which follows rewinding 3 6 8 File Protect This is a level which is true when power has been applied to the transport and a reel of tape without a write enable ring installed has been installed on the transport 3 6 9 High Density Indicator HDI This is a level which is true whenever the high density mode has been selected This selection may be accomplished by either an external HDS signal or the local HI DEN switch depending on which option is selected 9 1 IN TERFACE TIMING Figure 3 2 shows interface waveforms used for reading and writing 20 USEC MIN IFWDC IWDS TYPICAL IWDP IWDO 7 IWA
13. U4 U13 00 036 U2 U6 1014 00 037 U3 U5 U9 012 015 U17 00 012 011 1 16 00 011 08 018 00 038 010 U19 00 015 020 00 017 021 00 039 022 093 094 00 018 PARTS LIST FOR PCB ASSEMBLY DATA 20 355 REFERENCE DESIGNATION PART NUMBER 1 C4 00 140 0047MF C2 C8 C10 C14 C19 C32 00 146 3 3MF 00 145 22MF 00 140 0022MF 00 140 033 MF 00 140 022 C20 C31 C34 00 147 6 8MF 1C2 902 00 136 68PF 1C3 9C3 00 140 01 1 4 9 4 00 140 0068 1C7 9C7 00 140 001MF CR1 CR5 1CR1 1CR11 thru 9CR1 908611 00 021 Q1 191 901 102 902 00 020 Q2 Q3 103 993 194 904 00 019 R1 R5 R16 181 981 185 985 186 986 00 026 220 R2 R6 R11 R17 182 982 00 026 330 R3 183 983 184 984 00 026 1 8K R21 R22 R26 00 026 3 3K 00 026 390 00 026 270 R9 R20 R24 R33 1819 9R19 1R23 9R23 1R29 9R29 1R30 9R30 00 026 1K R10 00 026 22 R12 00 026 470 R13 00 022 1K R14 00 022 1 74K R15 00 022 1 15K R23 00 026 150 R25 R31 R32 00 026 2 2K R27 R29 00 022 4 99K R28 00 024 50K R30 00 024 20K 187 987 188 988 00 022 1 62K 1R9 9R9 00 026 27K 1810 9R10 00 026 8 2K 1R11 9611 00 022 178K 1R12 9R12 00 023 5K 1R13 9R13 00 022 34 8K 1814 9R14 1R15 9R15 00 022 10K _ A 10 PARTS LIST FOR PCB ASSEMBLY DATA A 20 855 Continued REFERENCE DESIGNATION 1R16 9R16 1R22 9R22 1617 9R17 1R18 9R18
14. deter mine which channel consistently arrives first After this measurement has been made the write one shot associated with the channel which arrives first should not be moved during succeeding adjustments 5 4 8 2 The adjustments of the other channels is performed by observing the skew waveform at 8 The waveform will roughly approxi mate that shown in the lower part of Figure 5 1 While the transport is both reading and writing adjust the one shot pots 1827 through 9R27 to try and make the waveform at TP8 approximate that shown at the top portion of Figure 5 1 5 5 MECHANICAL ADJUSTMENTS 5 921 Read Skew Adjustments This adjustment is not required unless a head is replaced or dam age to the head has occurred Under these circumstances the procedure out lined below should be followed First an 800BPI master tape should be loaded on the transport and the unit should be given forward command The read skew waveform at TP8 should be observed with an oscilloscope If read skew compensation is required the waveform will appear similar to that shown in Figure 5 1 properly adjusted unit will have 5 volt to 0 volt fall time of less than 14MS for the 12 5ips transport 5 5 dl Move the tape off of the head guide cap toward the spring loaded guide ring first on the right hand guide and secondly on the left hand guide If moving the tape on the left hand improved the skew the right hand guide should be shimmed out and
15. electrical and mechanical specifications for the units 1 6 INTERFACE SPECIFICATIONS Interface signals are standard DTL TTL levels Table 1 1 SPECIFICATIONS SUMMARY MODEL NO 87581 and 89081 TAPE SPEED 12 5108 DATA DENSITY 800 500 and 800 Table 1 1 Continued NUMBER OF TRACKS START STOP TIME INSTANTANEOUS SPEED VARIATION VARIATION OF AVERAGE SPEED START DISTANCE STOP DISTANCE REWIND SPEED DYNAMIC SKEW STATIC SKEW REEL SIZE RECORDING MODE HEAD TYPE TAPE TENSION TAPE SPECIFICATIONS ELECTRONICS INTERFACE WEIGHT MOUNTING DIMENSIONS INCHES HEIGHT WIDTH DEPTH TOTAL 7 IBM and 9 USASCID 30 0 2 0MS 3 maximum 1 maximum 0 19 0 02 inches 0 19 0 02 inches 125ips nominal 75 microinches maximum 100 microinches maximum to 8 5 diameter IBM compatible Non Return to Zero Single gap with full track erase 8 0 1 2 oz 0 5 inches wide 155 mil thick computer grade silicon solid state DTL TTL 35 pounds Standard 19 inch rack mount 12 25 inches 19 00 inches 12 5 inches 1 3 Table 1 1 Continued DEPTH FROM MOUNTING SURFACE 10 6 inches POWER 115 230VAC 48 to 440Hz 100 volt amperes OPERATING TEMPERATURE ROOM AMBIENT 40 F to 115 F RELATIVE HUMIDITY 15 to 95 non condensation ALTITUDE 0 to 20 000 feet TRUE LOW 0 to 0 4V FALSE HIGH 2 to 5V 1 6 1 Wires disconne
16. no shims are available the entire arm may be moved in or out by loosening the screw holding the arm to the shaft Care must be exercised to avoid rotating arm with respect to the shaft 5 5 7 Write Enable Solenoid Assembly Adjustment The write enable solenoid assembly is designed to detect the pre sence of a write enable ring in the tape reel A spring mounted pin extruding through a hole in the mounting surface is pushed back through its hole by the write enable ring When it is pushed back this pin causes normally open contacts of the write enable switch to close After the LOAD switch is de pressed for the first time the write enable solenoid latches the write enable switch close causing the pin to retract even further If no write enable ring is present the pin remains extruding through the hole in the mounting surface Adjustments should ensure that first if no write enable ring is present the pin does not rub against the reel and secondly if a write enable ring is pre sent the pin retracts to its proper position De Oe tat Begin the adjustment by measuring the distance that the pin trudes above the tape reel mounting surface of the reel hold down assembly This distance must be 0 06 If it is not adjust the pin locking nut until the proper distance is obtained second adjustment involves proper positioning of the write enable solenoid on the mounting bracket This adjustment must be performed if it is determined tha
17. the braking action will take too long resulting in tape spillage Clearance should be 010 to 020 5 5 5 1 If it appears that brakes are not properly adjusted loosen the two cap screws which hold the solenoid for the respective brake that needs adjustment and move the solenoid slightly inward or outward as required Tighten screws and test the transport to ensure proper adjustment has been obtained 5 5 6 Roller Guide Adjustment Take up roller guide controls tape movement on and off of the capstan It requires adjustment only under unusual circumstances such as when the motor assembly is changed To perform this adjustment cycle the transport with an external controller so that the unit moves repeatedly for ward and then reverse Observe the spacing between the outer edge of the capstan and the edge of the tape II this distance is quite different when the tape moves forward from the distance observed when the tape moves in erse then an adjustment of the take up roller guide is required This adjust ment is performed by shimming in or out the roller guide until the distance specified above is approximately equal in the forward and reverse direction The shims are inserted by removing the cap screw holding the guide insert ing or deleting shims use WL Part No 00 083 and then replacing the guide and screw A certain amount of experimentation is required to determine the exact number of shims required If
18. 0 NFWD 10 1 O4 2 N BOT lt B gt REV CRIO4 ov REVERSE 5V m 220 NBOTD J1 C O M IFWOC 330 PHOTOSENSE 5 2222 SELA ROS R108 257777275 MOTION NBOT JI 30 OV 47K 75 5V 4 R107 0 022 SEL 6 220 8 2 R105 12 6 9 1 NBOT UAA U5A O 6 220 QU6B D 9044 5 0 01 161 TP62 10 T C101 106 TP35 CV 1960 38 4 O JI T TP37 5v o NRDY gt 1 12 72 0 IRDYI 22 4 5 6 NWRT O j 1 2 U7A NOLN O TP39 OV O J146 R110 T TP1 3 19 K 2 E 12 SEL TP43 NRWD tov 842 v Q101 TP44 NRWA 2203 NA J Q 2k 845 R116 AUN 1 5K 5N NFLR 12 440 3 9 LOAD 50 LOAD 8 TP47 NRESET R117 220 BOT 1 6 4 UGA NRWA 104 0 001 Hi TP51 0 4 JI N ces UBB IRWDI OV O J1 12 5 cioe 22 10V TP56 INTERLOCK TP52 D NRE SET 15 8 5 O 19 O NRDY RWD TP53 4 LOAD pa NBUSY 408 3 13 1 1 3 2 5 6 121015 AP AUIS 8 2 OLN G O RESET NFLR FLR TP54 TP55 IFPI SEE O J1 P OV O J1 13 J2 14V 5V 14 WRT PWR NHID TO DATA BOARD MOT ION 5V GRD 2 4 5 6 7 8 9 NWRT SH 1 FOR GEN NOTES amp REVISN WILLARD LABS INC
19. 00 019 NOTE UNLESS OTHERWISE SPECIFIED REVISIONS 2 ES deem ADDED C24 TP2 44D quD 72 12 3 REMOVED 2778 JUPE Z 7777 FSV FROMM 7 5 2 ADDED 03 ADDED C 7 2 SUMPEL WAS RIGE ABWE Cu st 5 PLA 20 33 224 _ 54 7007 346 5V0C LEFT REEL ee Teno m Jang dos don Jeng 3 3 15 VERSION TABLE bi u2urus v MX v R pill c i I o MI al ws aoe CRH CRIIO R55 R151 R143 148 2 36 37 44 45 24 C118 419 NTEGRATED PART NUMBERS REF DESIG PART NO U3 U5 U9 U12 U15 U17 00 012 U1 U4 U13 00 036 9 _ 00 015 _ 02 06 04 U22 U23 U24 00 018 gt IDENT NO 34358 WILLARD LABS INC BE con 7 1 120 65 i SH 1 OF 2 8 7 6 5 5V R118 5K o bs 11 0103 TP 69 lt R131 R130 15K TP29 TP30 905 220 te 5 UI8A 2 0 Jt u M 5 8 204 J Q NOLN pes 41 5 GIAL Spr 4 7K NLOAD f FWD T 13 CR102 9 d 2 OLN O NEOT 0 5 5V Sp O JI M FORWARD 6 10 SELA i 067 11 10 ON LINE 6 127 LU 3 NRDY TUR pss Ov O 1 1 OLN 15 l nreseT4 5V 183522 126 TP66 417 R102 ES 33K hid 1
20. 20222 5 288 2 11 2810 AF 2R13 9 2CR5 EF C 3611 3R13 3 Mw Sas URBES 3R8 V 401 44 Y 3612 xo S 48 L d 4812 489 M amp E ACRS pl C 21 4mig 453 5 sRij S 5 85 5 12 C oc 10 c Tek 5 2 z ce Ul Hd agri ra se 6812 29 5 1 I 6R10 CRIA CHE 4 5CR2 522 I 502 6811 6813 9685 gt 7813 7CR5 zag R10 5 gt OR Re U20 7 TR C22 8C1 E Y 8R12 8R 7R8 poe 9 8CR5 XI ae 9R13 9CR5 Pl EO 9812 802 Ova 9810 8 R4 ara 8R8 m E a v oO TON c23 e COED C565 9 9R11 U21 988 27 GND oe INDICATES PLUS SIDE TYP 1 SEE NEXT ASSY FOR PARTS NOTES PN20 357 RUBBER STAMP ASSY NO WITH REV LTR 12 HIGH C15 1R 21 1822 1 8 ICR8 XI IC4 H ICRIO 16 24 1 9 XI D 23 1687 194 1 5 2622 Q 9 otaa hi 4 2CRI1 204 14 2CRIO 2824 2CR9 XI D 2R 23 2CR7 204 9 28 21 2 5 3822 amp 14 3 11 3c4 1 3R 24 3CR9 D 3R 23 3CR7 304 2821 3 5 4822 5 5 I4 11 4CR9 XI 4823 4 7 404 9 C29 5 R21 4 5 5822 2818 0 mme o 0 Vd cns ei 4 5CR11 504 450810 5624 5CRO Pi D 5R23 5CR7 504 9 up Lo
21. 290 6 32 HEX NUT 27290 00 76 TERM LUG 18 TRANSISTOR Z REF ELECT SCHEMATIC 20 6 5 C C FINAL PART REMOVE TAG AMD RUBBER STAMP ASSY VO REV LETTER APPROX WHERE SHOWA RLF DWG 20 248 20 2439 WHEN 476 TRAMS TORQUE TO EXCEED 8 074 28 4 SEE DWG 20 063 FOR SUMPER 37 444 4 SEE ut FOR PARTS Gore PART IDENTIFICATION OF SUB ASSY APPLY REMOVABLE ILLARD LABORATORIES INC WEE 9 9794 9 2 QII OW HEAT SINK TO MATCHING gt 5404 22222 QD APPLY THEMAL COMPOUND 586470 OM BOTH SIDES 7 LLECTROWC COMTROL ASSY BASIC OF MICA WASHER PRIOR TO WSTALLATION Wore 5 _ 00 033 eod 9 eoo 913 C8 2 9n gt c 24 R26 0 R25 sod cz 126 R29 y x R22 R4 R8 1 R7 LL 40 m 1 ia T p 9 R14 7 T F 02 m 3 18 281 22 06 F 3R2 481 9 581 681 781 qe 7R2 R 92 T GND 00 032 PIN MALE 82 REQD FEMALE 012 013 014 015 016 00 119 CAPTIVE SCR 2 REQD s C26 is a T Le m TR5 187 IR12 1 UU ig uM E C 2765 201 5 287 45 quier 2812 e 5 4292
22. 3 RII 530 ERASE CI 270 186 0V 8 05 42 41 5 NHID gt 9 CHANNEL 6 IR2I 1R20 MEG 100K ICR9 ICRIO L5V TPi2 3 3K MOTION 21 6 4 2103 1 IRDP JIO3 A J103 3 IRDO J103 C J103 4 J103 D 2105 8 IRO 2 JIO3 J 2105 9 IRD3 JIO3 K 2103 14 18004 2103 2103 15 1605 105 5 7103 17 IRO6 J O3 U 3103 18 IRD J105 V 5 R20 EDIDI KC DAR AWM WTA CHANGES SILKSCREEN ADDED 00 032 776 57 MALE PIN 2 o 2 6 20 34 4 hee 00 033 8 REQD 2 7001 p Q 20 023 RED ee O iiim 1301 C C 8 998 868 I2 JH Jio 115 J04 1 17 J18 J19 107 108 956059 oco oo o sd oo e o 4 9915 OO o o o alls 4 C eo oo 5 os te I I o o 9 9 0 zo e gt 0105 9 c lo 0106 0102 0101 i 2 25 O Ta 14 56 Q We 916 112 60 L JI R121 112 R141 D so 02 399 43 K CRIO2 R118 5 J2 22 118 35 459 9 W U4 DATE 2H GH 2 R150 33 176 F cio2 1 wD 961 D
23. 6 ELECTRONICS CONTROL ASSY PCB ASSY DATA A 3 20 355 4 20 364 WRITE ENABLE SW ASSY 5 20 246 MAG HEAD amp DRIVE ASSY NO PWR amp HI DEN SW REPLACES 20 118 CONTROL PANEL ASSY 9 20 337 7 20 341 POWER SUPPLY ASSY ASSY 20 320 8 9 20 309 20 342 HARNESS 55 PCB ASSY PWR FAIL RESTART a 2 O o o gt M CODE D DETAIL PART WITH A ASSY WITH B M R REFERENCE DOC 5 SHIP SEPARATE WILLARD LABS BILL OF MATERIAL TITLE TRANSPORT ASSY MOD 875815 B M NO 20 370 COMPILED BY DATE CHECKED BY DATE DATE ISSUE 9 LEE 2 18 72 T USED ON WG 517 NEXT ASSY is SHEET 20 320 TRANSPORT ASSY BASIC SEF ITEM 7 21 20 333 ELECTRONICS CONTROL ASSY PWR FAIL OPTION 2 s 20 160 MAY 20 355 ASSY DATA A USED 20 36 WRITE ENABLE SW ASSY 5 20 244 MAG HEAD amp DRIVE ASSY 20 337 Tl 205341 NO PWR amp HI DENS SW _ REPLACES 20 118 ASSY 20 320 CONTROL PANEL ASSY POWER SUPPLY ASSY 9 20 342 HARNESS ASSY 20 309 ASSY PWR FAIL RESTART 20 368 CONNECTOR HI amp LO DENS SWITCHING 1 L gt N GQ m gt x G N gt CODE D DETAIL PART WITH ASSY WITH B M R REFERENCE DOC 5
24. A pin 6 to go low provided that the unit is not at the end of tape NEOT low and it is not moving in the reverse direction NREV low When U2A pin 6 goes low CR102 is forward biased and the forward ramp begins In addition U1A pin 12 goes low thus causing the unit to latch up in the for ward direction until EOT is sensed Similarly when the REVERSE switch is depressed U2B pin 8 goes low and UIC pin 6 goes high This action causes the reverse motion ramp to be energized the unit is in forward motion NF WD low or it is at the beginning of tape NBOT low reverse motion is halted 4 2 3 Rewind Command The rewind command will be considered first for the case of the tape not at the load point and secondly for the tape at the load point 4 2 8 1 Tape Not At The Load Point When either an external or manual rewind command is given the tape rewinds to the load point It does so by moving backwards to the BOT tab at the rewind speed overshooting the BOT and then moving forward to the load point Figure 4 3 shows the waveforms associated with this move ment 4 2 3 1 1 The rewind command causes the RWA output of flip flop U11A to go high This action causes the rewind ramp to begin The re wind will continue until the BOT tab is encountered causing RWB to go high and the one shot U20B to fire 4 2 3 1 2 tape has overshot BOT and NBOT has gone low LOAD flip flop will be reset from the clocking ac
25. Any other solvent such as carbon tetrachloride may result in damage to head lamination adhesive 2 The guides must not be soaked with excessive solvents Excess solvent may reach the guide bearings breaking down bearing lubricant 9i Do not use excessive solvent on the take up hub retention Strip Excessive solvent may damage the strip 5 3 2 To clean the tape cleaner remove the red plug from the front of the cleaner clean with a cotton swab and replace the red plug To clean the capstan use cotton swab moistened with XYLENE and remove all dirt and oxide roller guides are to be cleaned with a lint free cloth or cotton swab moistened in isopropyl alcohol guide surfaces must be cleaned so that all dirt and oxide are removed 5 4 ELECTRICAL ADJUSTMEN TS The following adjustments refer to components shown on drawings 20 162 or 20 358 20 182 for read after write version and control schematic located in the Appendix 5 4 1 Tov lator The 5 volts should be adjusted by using a very accurate volt meter between TP5 and ground on the control board Potentiometer R1 Should be adjusted until the voltage reads 5 1 0 05 volts This voltage must be adjusted prior to making any speed adjustments 5 4 2 5V Regulator The regulator tracks the 5V regulator but has no independent adjustment To assure that this regulator is operating properly place a voltmeter between TP and ground This voltage should r
26. E 6 P Cs 23 __ 53 41 Dens 29 i yj C 37 1 240 ASSY No m 74 05 2 4 uU 5 7 E O meas UR _ 2 25 77 8 HIGH 2 48 o 34 6 49 51 9 7RACK xixi xlix i O us p o uz 666 118 L 429 F 59 9 68 POMENIT SIDE 2 918 540 P 69 lt t Lj CI14 5 R124 973 GND O E U 31 29 GND 67 E 4 813 211 106 76 8125 2o ar A eo p 46 ump x E C E R144 e H d C105 02 3 5 0 2 TRANSISTOR MTG PAD TYP INSTALLATION 05 06 C 9 3 7 2 Qoa FOR 02 9 4 Qe 920 Z REF SCHEMATIC 20 6 5 33522 VERSION TABLE FOR INSTALLATION OF SUMPERST THRU Y 2 STAMP REVISION LETTER ASSY DATE APPROX AS SHOWN DOT ow CAPACITOR INDICATES PLYS SIDE NOTES SEE 8 47 FOR PARTS WILLARD LABORATORIES Inc 47 REDWOOD AVENUE TS ANGELES 90066 ASSY COKATRO PROS 007 65 I 512 CODE 20 57 007 34358 APPLICATION scat 27 12 ser Z ING ESN aB 97 ON n E A
27. ES TITLE Interface Configuration Wiring Diagram For Power Tape Threading Waveforms For Reading And Writing Organization Of The Transport Load Sequence Waveforms Waveforms For Rewind To Load Point Inter Record Gap Format For 9 And 7 Tracks File Gap Format For 9 And 7 Tracks Skew Waveforms Tape Tension LIST OF TABLES TITLE Specifications Summary Power Connections Interface Connections PAGE Appendix 1 4 2 2 3 2 3 8 4 2 4 4 4 8 4 11 4 13 5 5 5 7 SECTION I GENERAL DESCRIPTION 1 1 INTRODUCTION This manual provides operation and maintenance information for a Willard Laboratories series of synchronous tape transports Those models which are described in this manual are given in Table 1 1 1 1 1 These transports all have tape speeds of 12 and can record in either 7 or 9 tracks depending on the model In the 7 track models densities are available ranging from 556 or 800BPI In the 9 track model data recording is performed at 800BPI 1 1 2 Data recording on all transports is IBM compatible The recorded information may be completely recovered when played back on an IBM digitaltape transport or its equivalent In addition these units are plug for plug compatible with many other industry transports 1 2 PHYSICAL DESCRIPTION Figure 1 1 shown in the Appendix the outline and installation drawing shows the standard dimensions for these models The units are designed to b
28. ES 3X 02 XXX 7 005 CORPORATION 0005 6019 ARE EXCLUSIVE PROPERTY OF PRODUCERS PRODUCERS SERVICE CORPORATION A SUBSIDIARY OF BOOTHE COMPUTER CORP GLENDALE CALIFORNIA 91201 PCB ASSY DATA A 20 37 DO NOT SCALE DRAWING sr SCALE 7 2 5 72 nw Z eee ENGINEER PROJ APPVL J 14V S V 14 WRT PWR NHID MOTION 5V GND NWRT O On Om A win wosl twans tea IWDP IWDO 0 Iw02 IWD3 1804 1405 IwD6 Iw07 m m 4 C8 CIO 5 5 15 C20 22 2 24 20 6 8 20 IRD2 IRD4 1807 CI4 C15 CI6 CIS 14V C26 C27 c28 C29 C30 1 IRD3 5V REF DESIGNATION LAST USED 916 TPi4 NOT USED II CI3 IC6 9C6 C3 IC5 9C5 _ 6 SEE VERSION TABLE FOR VALUES 5 FOR ASSY SEE 0wG 20 37l 4 U12 THRU 16 ARE 09 181 052 33 35 37 38 00 180 U1 5 6 ARE 00 012 U4 amp U31 ARE 00 015 17 THRU U21 ARE 00 014 U3 15 00 015 934 amp 056 00 016 U2 15 00 017 022 THRU U30 ARE 00 018 3 ALL CAPACITOR MICROFARADS 2 ALL DIODES 00 02 ALL RESISTORS IN OHMS 1 4 w 5 NOTES UNLESS OTHERWISE SPECIFIED fee 00144 5 2 VERSION TABLE
29. ODUCTION 2 FUSE REPLACEMENT TRANSPORT CLEANING 4 ELECTRICAL ADJUSTMENTS 5 4 1 5V Regulator 5V Regulator BOT And EOT Amplifiers Ramp Timing Tape Speed Read Amplifier Gain Read Data Strobe Adjustment Write One Shot Adjustments _ Performed After 5 5 1 CI gt 2 PO 47 gt Q C3 II I I l l gd d d gg i OOO o C9 i it d 1 l l CO d TABLE CONTENTS Continued PARAGRAPH 5 5 MECHANICAL ADJUSTMENTS 5 5 1 Read Skew Adjustments 5 5 2 Replacement Of The Precision Magnetic Head And Drive Assembly Reel Servo Belt Tension Tape Tension Reel Brake Adjustment Roller Guide Adjustment Write Enable Solenoid Assembly Adjustment 5 5 8 Arm Limit Rubber Bumpers OF IO OF BP APPENDIX A Bill Of Material spare Parts List Part Number Cross Reference Parts List For Power Supply Assembly 20 118 20 341 Parts List For PCB Assembly Control 20 1631 Parts List For Assembly Data 20 355 Power Fail Restart Option WLI Part No 20 309 and 20 344 Parts List For PCB Assembly Power Fail Restart 20 309B A 10 12 14 FIGURE TABLE LIST OF FIGUR
30. OPERATING AND SERVICE MANUAL WILLARD MODELS 87XX1 AND 89081 READ WRITE TAPE TRANSPORTS 1971 BY WILLARD LABORATORIES INC 4221 REDWOOD AVENUE LOS ANGELES CALIFORNIA 90066 REPUBLISHED OCTOBER 1972 BY GTEIS NOVAR CORPORATION 2400 CHARLESTON ROAD MOUNTAIN VIEW CALIFORNIA 94040 11 FOREWORD GTE Information Systems republishes this Operating and Service Manual by prior arrangement with Willard Laboratories Incorporated Los Angeles California The manual is republished GTEIS Novar Corporation s standard format and type style and with retouched and or redrawn illustrations The con tents and technical accuracy are the same as the original manual Additional copies of this manual should be requested from Product Support Publications 2400 Charleston Road Mountain View California 94040 TABLE CONTENTS SECTION PARAGRAPH 1 GENERAL DESCRIPTION 1 1 INTRODUCTION 1 2 PHYSICAL DESCRIPTION 1 3 FUNCTIONAL DESCRIPTION 1 4 POWER REQUIREMENTS 1 5 ELECTRICAL AND MECHANICAL SPECIFICATIONS 1 6 INTERFACE SPECIFICATIONS 9 INSTALLATION AND INITIAL CHECKOUT 2 1 INITIAL UNCRATING OF THE TRANSPORT 2 2 POWER CONNECTION 2 3 INITIAL CHECKOUT 2 4 INTERFACE CONNECTIONS 2 5 RACK MOUNTING THE TRANSPORT 3 OPERATION 3 1 INTRODUCTION 3 2 LOADING THE 8 3 UNLOADING THE TAPE 3 4 MANUAL CONTROLS 3 4 1 POWER 3 4 2 LOAD 3 4 8 REWIND 8 4 4 ON LINE 3 4 5 WRT EN Write Enable 3 4 6 HI DEN High Density Optional
31. REVERSE switch This switch is enabled only in the off line mode of operation and has no lamp associated with it Motion will cease Hu the tab is encountered or if RESET switch is depressed 3 4 9 RESET In the off line mode of operation depressing the RESET switch will cause the transport to stop forward or reverse motion or stop rewinding If the transport is in the on line mode of operation depressing the RESET switch will cause the unit to revert to the off line mode 3 4 9 1 The RESET switch has no effect on the WRT EN the HI DEN the LOAD or the POWER switch 3 5 INTERFACE INPUTS The following is a description of the interface signals which must be supplied from the customer controller to the transport names corres pond to the true level of 0 volts Barred terms correspond to a false level which is between 2V and 5V schematics show interface signal symbols prefaced with an I to indicate a signal transmitted to or from an interface 3 5 1 Select SEL This level when true enables all of the interface inputs in the transport thus connecting the transport to the controller All of the inter face inputs are gated with the SELECT signal 3 5 2 Forward Command EWDO This level when it is true and the transport is READY causes the tape to move forward at the specified velocity A false level of this com mand causes tape motion to cease The velocity profile is trapezoidal with nominally e
32. RS NRZI 1 LI FLUX PATTERN DATA PATTERN 01 101 1 CRCC LRCC WRITE WAVEFORMS IFWDC TYPICAL READ PATTERN TYPICAL READ DATA IRDS DATA PATTERN 011011 READ WAVEFORMS Figure 3 2 Waveforms For Reading And Writing SECTION THEORY OPERATION 4 1 INTRODUCTION This section explains the operating theory of the various trans port components The transport is subdivided for purposes of analysis into the following subassemblies 1 Control Logic 2 Power Supply 9 Capstan Drive Tape Storage and Reel Servos 4 Data Electronics and Magnetic Read Write Heads 4 1 1 Figure 4 1 shows organization of the transport in terms of the two PC boards and the interconnected subassemblies The first of the two PC boards contains the control logic the capstan and reel servo amplifiers the voltage regulators the interlock relay lamp drivers and photo tab sense amplifiers Interconnecting plugs on the board connect the board circuitry with the control panel lamps and switches the motors the tension arm position sensors the limit sensors and the unregulated sup plies A printed circuit edge connector is used for transmitting control sig nals to and from the interface 4 1 2 The second board containing data electronics is concerned only with reading and writing of data Data to be written enters the board through one of two edge connectors It is transmitted to the head through a conn
33. S time For recording to occur the transport must be in the write mode of operation Data lines must be held steady for a period of 0 505 before and after WDS pulse occurs 3 5 7 Write Data Strobe WDS This is a pulse of minimum width 2US which is used as a clock to write data onto tape One pulse is required for each character to be recorded Itis assumed that data lines have settled at least 0 505 before the trailing edge of this pulse occurs and will remain steady until 0 5US after the trailing edge of this pulse 3 5 7T 1 In 9 channel systems an additional WDS pulse is required to write the Cyclie Redundancy Check Character CRCC four char acter Spaces after the last data character 3 9 8 Write Amplifier Reset WARS This is a pulse of minimum width 2US which is used for writing the Longitudinal Redundancy Check Character LRCC 7 track systems the front edge of the WARS pulse occurs four character times after the trailing edge of the WDS associated with the last data character In 9 track systems the front edge of the WARS pulse should occur eight character times after the WDS associated with the last data character 3 5 9 Read Threshold RTH This signal used only in the 81 model transports single gap heads selects one of two read amplifier threshold levels A true level selects the higher threshold while a false level selects the lower threshold In the 82 model transports read after write the
34. amp SERVO PWR LOAD PUSH BUTTON LOAD FF BOT TAB NBOTD FLR LATCH NREADY TAPE VELOCITY NLDP pe U U U U U U S ae ST _ _ TURN PUSH LOAD PUSH LOAD BOT TAB POWER BUTTON 15 TIME BUTTON 2ND TIME UNDER ON SENSOR Figure 4 2 Load Sequence Waveforms ramp generator which drives capstan servo If tape is loaded at some point prior to BOT it accelerates to its full speed and moves until it reaches the BOT sensor When it reaches BOT the BOT signal goes high Hence pins 1 2 4 and 5 are all high resulting in the LOAD flip flop being set This causes the tape to decelerate and come to rest under the BOT If the tape was loaded at a point after BOT depressing LOAD a second time will cause the tape to move forward and continue to move until physical end of tape is reached It will not stop at To stop movement depress the set button 4 2 1 3 2 At this time U10A pins 3 4 and 5 are all high See remainder of section for explanation of why NBUSY AND FLR are high causing NLDP to golow This action causes the load lamp to be lighted It will re main in a lighted condition until the tape moves away from BOT The BOT tab is sensed by a photoelectric transistor whose output is transmitted through amplifier Q107 to a schmitt trigger 020 Whe
35. and C2 to form the two unregulated voltages The auxiliary voltage is also unregulated and is formed with rectifiers CR10 and CR11 and capacitor C22 An auxiliary vol tage is necessary so as to provide quick turn off for relay K1 and brakes 1 and 2 in the event of a power failure 4 3 1 Regulator 021 used along with power transistor Q1 forms 5V The 5V source is derived from 5V through op amp 022 and power transistors Q2 and 921 SCR 020 senses the 5V supply for over voltage If something should cause this voltage to increase to about 7 5V the SCR will fire thus shorting out 14V supply until the fuse blows 4 4 SERVO AMPLIFIERS AND TAPE STORAGE SYSTEM In this section the capstan servo amplifier system and the reel servo amplifier system will be described 4 4 1 Capstan Servo The capstan servo amplifier consists of a motor tachometer com bination along with an amplifier and ramp generators Relay is used to short across the motors in the event power is lost providing dynamic braking 4 4 1 1 ramp generator consists of U23A U23B 04 019 and associated circuitry When point A is brought to 0V transistor Q3 turns on and U23B begins the forward motion ramp from 0 to 5V Con versely when point B is brought high Q19 turns on and U23B begins the reverse motion ramp from 0 to 45V Potentiometer R19 controls the slope of the ramps while potentiometer R53 balances the two ramps so that f
36. be set The circuitry is now ready to receive the next set of data 4 5 3 2 6 duration of the one shot time is determined by which of the two one shots contained in integrated circuit U2 is selected Ifa 9 channel transport is used or if the higher density is selected in a 7 channel transport timing is controlled by R30 R29 and If lower density 7 channel transport is chosen R27 R28 and C6 determine the one shot time 4 5 3 2 7 7 channel version of this board is formed by omitting two of the nine channels 4 5 4 Dual Gap Option In the dual gap option a dual gap head is provided which has separ ate coils for reading and writing When this type of head is selected certain modifications to the data electronics are required 4 5 4 1 The major change over single gap case is the addition of de skew one shots U7 through 011 With the inclusion of these one Shots the WRITE DATA STROBE WDS is no longer transmitted directly to the write flip flop clock inputs Instead the WDS signal triggers the one shots which in turn drive the clock inputs of the write flip flops Hence a variable delay is provided which allows independent adjustment for each channel of the time between the WDS and the turn on of a write transistor The method of adjusting these one shots is included in Section V 4 15 4 5 4 2 Two other important changes over single gap case are included First diodes 1
37. cted from inputs are interpreted as false levels 1 6 2 Figure 1 2 indicates interface information for use in transmitting signals to the transport or receiving signals from it HIGH lt FALSE CUSTOMER LOW TRUE CUSTOMER WILLARD WILLARD 5 DTL994 DTL 836 844 862 7416 OR EQUIVALENT _ OR EQUIVALENT m Figure 1 2 Interface Configuration l 4 SECTION II INSTALLATION AND INITIAL CHECKOUT 2 1 INITIAL UNCRATING OF THE TRANSPORT The transport should be uncrated carefully so as to minimize the possibility of damage and to uncover any shipping damage or shortages Begin uncrating by placing the container in the position indicated on the con tainer Carefully remove the transport along with its shipping frame from the container and verify the packing slip Perform a visual inspection to ensure that all connectors and the plug in relay are properly seated The identification label on the back of the transport should be checked to verify that the unit is the correct model number and is set up for the proper line voltage 2 2 POWER CONNECTION If the actual line voltage at the installation is different from that shown on the transport change the power transformer taps as shown in Table 2 1 A power cord is supplied for plugging into a polarized 115 volt outlet For other power sockets substitute the correct plug for the one supplied with the unit A wiring diagram of the power transformer i
38. e mounted in a 19 inch EIA rack 1 2 1 Two hinged printed circuit boards contain the data electronics and control circuitry Interface signals are brought into and out of these circuit boards through three printed circuit edge connectors Access to these connectors is from the rear T 1 2 2 dust cover is provided to protect the magnetic tape the read write head and capstan from any contaminants Operational controls mounted on a control panel are accessible with the dust cover closed 13 FUNCTIONAL DESCRIPTION The transport may be broadly divided into the control section and the data electronics section control section consists of circuitry nec essary to control starting and stopping of tape motion while the data elec tronics consists of circuitry necessary to read and write information on tape 1 3 1 A single capstan drive is used for controlling tape motion during read write and rewind modes This capstan is controlled by a velocity servo which utilizes tachometer feedback information from the cap stan motor to control tape speed A ramp generator precisely controls acceleration and deceleration during starting and stopping 1 3 2 Independent supply and take up reel motors in conjunction with buffer storage arms maintain constant tape tension during the relatively fast starts and stops of capstan reel servo amplifiers sense the displacement of the storage arms by use of photoelectric sen
39. e reel of tape in position and push the lever back flush to the reel If it is desired to enable writing place a write enable ring in the reel prior to mounting d Thread tape along the path shown in Figure 3 1 This path also shown diagramatically on a decal mounted on the front of the transport retaining strip on the take up reel facilitates take up by ing the tape to adhere to the reel 3 2 2 Verify correct seating in the tape guides by manually rotating the supply hub Once the seating has been checked depress the POWER switch Next depress the LOAD switch allowing tape tension to be applied to the arms Examine the tape again for correct positioning If the tape is not seated correctly turn power off and reposition the tape After the tape has been properly seated press the LOAD switch a second time causing the tape to move to the BOT At this point close the dust cover and keep it closed during all subsequent tape operation 3 3 UNLOADING THE TAPE Begin unloading of a tape by placing the unit in off line control If the tape is positioned at some point after the BOT tab depress the REWIND button This action causes the tape to be rewound to the BOT point RE WIND button should be depressed a second time causing tape to rewind until tape tension is lost Open the dust cover and wind the tape onto the supply reel To remove the supply reel pull the lever on the reel hold down knob forward and
40. e when tape tension is lost and cause relay to disabled This action causes power to be removed from the motors and the brakes 4 5 DATA ELECTRONICS 4 5 1 Introduction Information is recorded in the Non Return to Zero mode In this system a 1 on the information line causes a change in direction in mag netization flux Figure 3 2 indicates the waveforms which occur during writing and reading 4 5 1 1 Since each 1 bit is recording as a flux transition and a 0 bit by no transition the read electronics must determine when a flux change occurred This determination is made by amplifying the read _ back signal and detecting where its peak occurred When the read electronics has determined that a transition or no transition occurred for all channels a strobe pulse is transmitted to the interface telling it to sample the data 4 5 2 Data Recording To record data a forward command IF WDC is first given in order to accelerate the tape to the prescribed velocity In addition the write enable command IWEC input line must be true the transport must be on line and the SELECT ISEL input line must be true After a time deter imined by the inter record gap the WRITE DATA inputs and the WRITE DATA STROBE WDS are supplied to the data electronics 4 5 2 1 WDS signal is used to clock flip flops whose J and K inputs are derived from the WRITE DATA signals These signals cause the flip flops to change s
41. ead 5 1 0 If it does not and the 5V has been properly adjusted the circuit should be examined for defective components 5 4 5 EOT Amplifiers When tape is loaded but neither the EOT nor the BOT tab is under its photo sense the voltages at TP73 BOT and TP71 EOT must read 8 0 volts minimum This minimum level is set by adjusting R121 and R118 respectively If either tab is under its particular photosense transistor the voltage at its corresponding amplifier test point must read 0 4 volts maxi mum 90 4 4 Ramp Timing The ramp generator controls the acceleration and deceleration times for forward and reverse motion Ramp timing is varied by adjusting R19 on the control board To adjust this time apply low frequency 5Hz squarewave to the FWDC input Observe the ramp time at TP11 and adjust R19 until the time is 28MS this pot is set and tape speed has been noted both the rise and fall ramps for FWDC and REVC should be mately equal 5 4 5 Speed Two potentiometers are used for controlling tape speed The first R21 controls the absolute tape speed the second pot R53 controls the balance between forward and reverse speeds 5 4 5 1 To adjust speed load transport with an all 1 s master tape Connect an electronic counter to any of the data channels 1TP6 9TP6 5 4 5 2 An iterative process is used for adjusting forward and reverse s
42. ector or connectors located on the board Data which is read from the tape and detected is transmitted to the interface through second edge connector 4 1 3 DC power and certain control signals are transmitted between the boards Both boards are individually hinged greatly facilitating accessibility for service 2 4 2 CONTROL LOGIC This section describes the logical control circuitry which regu lates tape motion Operation of tape motion controls will be described by detailing the following operations Bring to load point tape motion com mands after initial loading rewind command and unloading of tape Fre quent reference will be made to the Control Electronics schematics located in the Appendix 4 2 1 Bring To Load Point sequence of bringing tc load point will be considered both for the case when power is turned on with the tape loaded prior to the BOT tab and with the tape loaded at some point after the BOT tab The sequence for each case will be considered by detailing the logical operation occurring 4 1 INTERFACE SIGNALS POWER SUPPLY VOLTAGES AND CONTROL LOGIC SIGNALS INTERFACE READ AND WRITE SIGNALS 4 2 CONTROL PANEL SWITCHES AND INDICATORS CONTROL BOARD SERVO AMPLIFIERS REGULATORS RAMP GENERATORS INTERLOCK RELAY CONTROL LOGIC DATA ELECTRONICS BOARD MOTORS TACHOMETER AND BRAKES UNREGULATED POWER
43. er supply The is mounted on the Power Supply cover and held in place by two Screws 13 PARTS LIST FOR PCB ASSEMBLY POWER FAIL RESTART 20 309B REFERENCE DESIGNATION PART NUMBER C1 T 00 137 250MF C2 C3 00 137 100MF C4 C6 C7 00 140 0 047 MF C5 C8 E 00 147 6 8MF CR1 00 173 CR2 CR5 CR6 _ 00 021 00 048 Ul 00 036 U2 U3 e 00 012 R1 R2 R7 00 026 620 R3 R11 00 026 220 85 00 026 4 7K 00 026 1 2K 00 026 2K 00 022 2K 00 022 750 A 14 3RUNING 40 21 COLLECTOR WIRE EMITTER BLK WIRE BASE WHT WIRE 22 AWG TWISTED REF TRANSISTOR REAR VIEW TYP DES REF ONLY 78 32 x 246 CAP SCR HEX SKT 8 SP LOCK WASHER 8 FLAT WASHER Y 8 32 HEX 20 58 HEAT 8 REF OO G REF 00 115 SPACER 8 32 x1 2LG CAP SCR HEX SKT SP LOCK WASHER 2 PLACES EMITTER REF BASE REF 7 TRIM MICA WASHER 00 043 PWR TRANSISTOR QO 777 MICA S 3 PAWEL 20 C 8 CONTROL WG 32 x 38 LG PH SCR 66602 SP LOCK WASHER 6 2290 00 120 FIBRE WASHER GKEQD 20 157 REV___ DATE _ _ _ I MICA WASHER SUPPLIED 3X6 THRUST WASHER SUPPLIED 5 6 32 x3 8 LG SCR SP LOCK WASHER Z PLACES 6 32 5 16 PH SCR 6 FLAT WASHER SP LOCK WASHER 5 PLACES 46 32 HEX NUT G WASHER 27
44. ertain control signals are used to enable writing NWRT signal enables and disables the write flip flops When NWRT is high the set and clear inputs to the write flip flops are held low Thus both the Q and Q outputs are held high and therefore 1Q1 and 1Q2 are held OFF Hence no writing may be accomplished when NWRT is high When NWRT is brought low the set input to the flip flops is brought high while the clear input is brought high after a delay determined by R8 and C1 Thus the flip flops are left in the reset state Lowering NWRT also turns ON transistor Q1 allowing erase current to flow 4 5 3 1 4 Five volt power to write and erase is enabled by WRT POWER To enable WRT POWER a Write Enable ring must be installed in the reel Without this ring no power is available to allow write or erase current to flow in the drive transistors 4 5 3 1 5 MOTION signal prevents the write flip flops from changing status unless the tape is in motion When this signal is low all flip flops are held reset However the erase transistors Q1 and 1Q2 may still be enabled When MOTION is changed to a high level normal writing may proceed 4 5 3 1 6 The WRITE AMPLIFIER RESET signal IWARS is used to record the LRC character at the end of a record During nor _ mal write operations IWARS signal is held high When this signal is switched low all write flip flops are reset thus causing a 1 to be recorded in those channels w
45. g Write current magnitude is defined by 1R5 and 1R6 4 5 3 1 1 Recording is performed the NRZI mode Thus a 1 is recorded by changing the direction of current flow in the head winding Flip flop 012 enables write transistor 101 or 102 depending whether the Q or Q output of U12 is at the logical 0 level For a logical one data input the J and K inputs of U12 are held high allowing the clock to switch the flip flop to its opposite state For a logical zero data input the J and K inputs of U12 are held low preventing U12 from changing state when a clock pulse arrives 4 5 3 1 2 Clocking is accomplished by applying WRITE DATA STROBE IWDS signal The IWDS signal is inverted and transmitted to the clock inputs of all flip flops The data input signals come through the interface and are terminated by resistors 1R1 and 1R2 The data is in verted through U5 and transmitted to J and K inputs of flip flop U12 4 12 APPROXIMATELY 0 6 p st 4 4 8 CHAR CHAR CHAR SPACES FILE LRCC MARK LRCC LAST DATA FIRST DATA CHARACTER CHARACTER OF PREVIOUS OF PREVIOUS RECORD RECORD 9 4 i CHAR 4 APPROXIMATELY SPACES CHAR 38 Hal LRCC Hoe FILE MARK FIRST DATA CHARACTER CHARACTER OF PREVIOUS OF PREVIOUS 2 RECORD _7 TRACK Figure 4 5 File Gap Format For 9 And 7 Tracks 4 18 4 5 3 1 3 C
46. he time between the occur rence of the first channel of data information and the read data strobe is adjusted by use of potentiometers R30 and R28 To make this adjustment place the trigger channel of a dual trace scope at TP14 and monitor 10 Fora 9 channel transport adjust the delay between the voltage going high at TP14 and the end of the read strobe at TP12 positive going edge using R20 5a 4 7 1 For 7 channel transport first select the higher of the two densi ties and adjust the delay time using R30 and then select the lower of the two densities and adjust its delay time using R28 These delay times t be measured as described previously and have a value given in US by 5 4 8 Write One Shot Adjustments Pertormed After 5 5 1 The write one shots used only on the read after write units used to compensate for skew introduced due to writing f 15 x Fr 2 6 _ 10 250 where D is the recording density in bits per inch and 8 is the speed in inches per second 5 4 8 1 To adjust these one shots first adjust all write one shot potentio meters 1R27 through 9R27 to minimum resistance Secondly determine during read which channel arrives first To make this determina tion place one channel of a dual trace oscilloscope at TP14 Place the second channel of the oscilloscope successively at 1TP5 through 9 5 sure the time difference between the two traces of the oscilloscope to
47. hose flip flops were set 4 5 3 2 Reading During reading the write and erase transistors are helf OFF by the NWRT signal as described previously The read signal is therefore transmitted only to operational amplifier U17 Feedback resistors 1R9 and 1810 along with 187 establish the gain of this amplifier at DC This gain is such that in the absence of an input signal the output of U17 is held at approximately 0 volts Capacitor 1C1 provides a low impedance shunt at readback frequencies so that the AC gain of U17 is determined by 1811 1812 and 1813 along with 187 Resistor 1812 is a potentiometer which is adjusted so that the output of U17 is about 12V P P during read back Diodes 1CR1 1CR2 1CR3 and 1CR4 are used to prevent saturation of U17 during write operation The read signal is too low a level to forward bias 1CR1 and 1CR2 4 5 3 2 1 The output of U17 is transmitted to an inverter 022 Full wave rectification is provided by 1CR5 1CR6 and 1R17 voltage at which the diodes conduct is controlled by the voltage appearing at the emitter of Q2 This voltage is set at one of two levels depending on the logic state of IRTH If IRTH is low the emitter voltage of 92 goes to DC level of approximately 2 or about 45 of the read signal peak if IRTH is high the emitter of Q2 goes to a DC level of 1 4V or about 24 of the read signal peak 4 14 4 5 3 2 2 The rectified signal is transmitted to an emit
48. ition 00 026 Allen Bradley RCO7 5 1 4W Resistor Metal Film 00 022 RN60D 2195 1 4W Resistor Variable Multi Turn 00 024 Spectrol 41 2 1 XXX Cermet 15 turn PART NUMBER CROSS REFERENCE Continued WILLARD LABS MANUFACTURER DESCRIPTION OR PART NUMBER OR EQUIVALENT PART NUMBER Single Turn 00 023 Spectorl 53 1 1 XXX Cermet Transistors 00 019 Motorola 2N4123 NPN 00 020 Motorola 2N4125 Si PNP 00 040 Motorola 1090 PNP Power Darlington 00 041 Motorola 233053 Si NPN Power TO 5 Case 00 042 RCA 2N4037 Si PNP Power TO 5 Case 00 043 Motorola 258055 Si NPN Power TO 3 Case 00 044 Motorola MJE3055 Si NPN Power Plastic 00 049 Motorola 2N4441 Plastic Silicon E Controlled Rectifier 00 164 RCA 2N5323 Si PNP Fuses 00 084 Bussman or Slo Blow 00 085 Little Fuse Fast Blow PARTS LIST FOR POWER SUPPLY ASSEMBLY 20 118 20 341 REFERENCE DESIGNATION PART NUMBER C1 C2 00 52 22000 C22 00 53 1000 CR1 00 051 CR10 CR11 00 185 00 084 2 5 00 085 6 00 002 PARTS LIST FOR PCB ASSEMBLY CONTROL 20 1681 REFERENCE DESIGNATION PART NUMBER C3 C21 C23 C4 C5 C6 C16 C17 C107 C116 C11 C106 C12 C15 C21 C23 C117 C118 C119 C120 C103 C104 C105 _ CR2 CR3 CR8 CR101 CR104 CR106 CR108 CR9 CR105 CR109 CR110 91 Q7 98 012 018 92 914 916 Q3 019 0101 Q105
49. l Reverse Command REVC Rewind Command RWC Select SEL Write Enable Command WEC Off Line Command OFFC High Density Indicator HDI On Line Indicator OLI Rewinding RWD File Protect Indicator F PI At Load Point Indicator LPI d i A S i J 2 4 Table 2 2 Continued Transport Connector 36 Pin Etched PC Edge Connector Mating Connector 36 Pin Elco 00 6007 036 980 002 SIGNAL GROUND INPUT PIN OUTPUT SIGNAL T Ready Indicator RDYI End Of Tape EOT Write Data Strobe WDS Write Amplifier Reset WARS Read Threshold RTH Write Data Parity WDP Write Data 0 WD0 for 7 Write Data 1 WD1 Channel Units Write Data 2 WD2 Write Data 3 WD3 Write Data 4 WD4 Write Data 5 WD5 Write Data 6 WD6 Write Data 7 WD7 lt d Read Data Strobe RDS Read Data Parity RDP Read Data 0 RDO for 7 Read Data 1 RD1 Channel Units Read Data 2 RD2 Read Data 3 RD3 Read Data 4 RD4 Read Data 5 RD5 Read Data 6 RD6 Read Data 7 RD7 lt c tn zJ q gt 2 5 2 6 SECTION III OPERATION 3 1 INTRODUCTION In this section the manual operation of the unit is described and the functional interface signals are defined 3 2 LOADING THE To load tape on the transport pull the lever on the supply reel hold down knob forward place th
50. mitted SELA is always high signal is gated with all control sig nals which are transmitted external to the control board Once the ROS sig nal has gone high then the unit may receive external commands 42 23 Operation From External Commands If the ROS signal is high the receipt of an external forward or reverse command FWDC or REVC will cause tape motion In the case of FWDC command point A is brought low thus starting the forward ramp generator In the case of a REVC command point B is brought high thus enabling the reverse ramp generator During reverse motion the sensing of the BOT tab will cause reverse motion to stop However the NBOTD one Shot U20B will be triggered only if BOT is sensed during reverse motion No automatic halt feature is provided when the EOT is sensed during forward motion If it is desired to halt on EOT the FWDC signal must be brought high by the controller when the IEOT signal goes low 4 2 2 8 1 A forward or a reverse command will cause the MOTION signal U4A 6 to go high After delay of approximately 10US as determined by R107 and C101 pin 8 goes high This signal is differen tiated by C102 and R108 and used to clock the write enable flip flop U7A This flip flop will be reset if the WRITE ENABLE COMMAND is low Otherwise it will remain set This flip flop will remain set if the unit is _ hot ready not on line as controlled b
51. n BOT is reached the signal 020 pin 13 goes high This action triggers 100MS one shot 020 This signal labeled NBOTD returns to a low level at the end of the 100MS period causing U14A pin 10 to go high Thus U14A pin 8 the NRDY signal goes low as a result of all inputs to this gate being high Later it will be shown that the NRDY signal is one part of the ROS level which indicates when the transport is ready on line and selected 4 2 1 3 3 The FLR latch formed by the gates U13A and U13B is set when the LOAD flip flop is reset After the initial load sequence the FLR signal will go high inverse signal NFLR is transmitted to 040 pin 12 and used to prevent the LOAD switch from having any further effect on operation 4 2 2 Motion Commands After Initial Loading Of Tape In this section the logical commands required to place trans port on line and operate it from external commands will be discussed In addition description will be given of operation of the transport off line from the control panel switches 4 2 2 1 Depress ON LINE Control If the ON LINE switch is momentarily depressed the on line flip flop U16A is reset causing the on line indicator to be lighted In this condition the transport is on line and therefore cannot be influenced by de pressing any control panel motion command switches place the unit back in the off line status the RESET switch should be depressed If jumpe
52. nsistor Q108 This transistor energizes the write enable solenoid which holds the switch closed This action results in WRT PWR being held high 4 2 1 2 2 Right and left arm limit sensing is provided by two photoelectric transistors When the arms are positioned the photoelectric transistors are energized and present a low impedance to ground Thus the base of Q109 is held one diode drop above ground and relay is held ener gized even though the cathode of CR108 was only momentarily grounded If at any time either one of the arms should move outside the normal operating range so as to block light from its associated photoelectric transistor relay will be de energized thus removing power from the motors and applying the reel brakes 4 2 1 3 Depress LOAD Switch A Second Time Depressing the LOAD switch the first time does not effect the LOAD flip flop U7B because this flip flop is held in the set condition until after relay 1 is energized This set condition 15 a result of the signal NRESET TP 56 being held low until INTERLOCK TP 26 reaches a high level Once relay closes INTERLOCK goes high NRESET goes high and flip flop U7B is no longer held in the set condition 4 2 1 3 1 Depressing the LOAD switch the second time causes to re This reset action means that signal NLOAD goes low which in turn forward biases diode CR101 This action enables the forward 4 8 p POWER INTLK
53. ort edge connectors through a harness of twisted pair wires These twisted pairs should have a maximum length of 20 feet and should be 22 or 24 gauge wire with at least 1 twist per inch The three printed circuit edge con nectors should be wired by the customer and strain relieved for flexibility Table 2 2 gives the pin numbers for the interface signals 2 3 2 5 RACK MOUNTING THE TRANSPORT The tape transport may be rack mounted in a standard EIA rack Figure 1 1 illustrates the location of rack mounting holes as well as dimen sional information for installation Use the following procedures for rack mounting the transport 1 Place transport flat surface with reels facing forward 2 Remove the three No 10 cap screws holding the transport to the shipping frame 3 Locate the socket wrench supplied with the transport Place the transport position in the rack and insert two socket head screws in the access holes on the left of the transport Do not yet tighten these screws 4 Place the single screw in right hand screw hole and tighten using the socket wrench De Tighten the two screws on the right side using the socket wrench Table 2 2 INTERFACE CONNECTIONS Transport Connector 36 Pin Etched PC Edge Connector Mating Connector 36 Pin Elco 00 6007 0836 980 002 SIGNAL GROUND INPUT PIN PIN OUTPUT SIGNAL 1 Forward Command High Density Select HDS Optiona
54. orward and reverse motion are equal 4 4 1 2 The output of ramp generator is brought through a voltage divider to the servo amplifier It is summed with the tachometer feedback signal in operational amplifier U22A Speed is controlled by poten tiometer 821 4 4 1 3 When rewind command is given point is brought high Q9 is turned off Q10 is turned on and the rewind ramp begins The rewind voltage is transmitted from the emitter of Q10 to R30 and summed with the tachometer feedback in U22A CR9 R52 and CR8 limit the maximum re wind speed to remain within the capability of the reel servos 4 4 2 Reel Servos Right and left reel servo amplifiers U24A and U24B are used to position the tension arms so as to maintain an approximately constant tape tension These servo systems work by sensing tension arm angular position with a photosensitive potentiometer which produces a voltage output in ratio 4 9 f to arm position The output of the sensors is amplified and drives the reel motors which in turn drive the left and right reels through pulleys These reels cause the tape to tension such that the tension arm spring tor que balances the reel motor torque when the arms are centered During the fast rewind compensating voltage is applied to U24A through R35 and R38 and to U24B through R42 and R46 This compensation helps keep the arms centered during the fast rewind 4 4 2 1 Photoelectric transistors sens
55. peeds First run the transport in the forward direction with the master tape and adjust R21 until the counter reads the specified frequency 5 10KHz for 800BPI and 12 5108 Next run the tape in the reverse direction and record the frequency Fr Takethe difference f between this recorded frequency and the specified frequency Adjust R53 until the reverse frequency is X Repeat the entire process by again adjusting the forward speed for the specified frequency and again adjusting the reverse speed for X After two to three repetitions of this process the speed should be within the required accuracy 5 4 5 3 rough of forward and reverse speeds may be obtained by placing the unit under a flourescent light and observing the strobe disk which is mounted on the capstan cover The spokes of the strobe disk should have approximately equal movement in the forward and the reverse direction 5 4 6 Read Amplifier Gain The read amplifiers on the data board are each independently adjusted by means of the single turn pots 1R12 through 9R12 The gain should be adjusted by using an all 115 tape previously recorded on unit to be adjusted Adjust each of the amplifiers so that the output is an approximately sinusoidal voltage of magnitude 12 0 25 volts peak to peak 5 4 7 Read Data Strobe Adjustment To adjust the read data strobe read a tape which has been recorded at the lowest density available on that transport T
56. pping but not so great that overloading occurs 5 5 3 1 Measure tension by deflecting the belt midway between motor shaft and the reel hub with a force of approximately 7 oz This deflection may be performed by pushing on the belt with a force gauge sure the distance that the belt deflects from its rest position This distance must be approximately 0 30 5 5 4 Tape Tension Tape tension is measured at each of the arms with a force gauge This tension must measure 8 1 4 oz If it does not loosen the cap screw which holds the angle bracket that is providing spring tension Rotate the angle bracket until the force reads 8 oz the gauge and retighten the screw Refer to Figure 5 2 for proper measurement of tape tension 1 2 MAGNETIC TAPE CAP SCREW WITH LOOP ON BOTH ENDS FORCE GAUGE HOLDING BRACKET 4 SCREW HOLDING BRACKET FORCE GAUGE TAKE UP REEL Figure 5 2 Tape Tension Adjustment 5 1 5 5 5 Reel Brake Adjustment The reel brakes must be adjusted so as to provide a minimum of movement upon release Begin this adjustment by depressing the POWER switch and depressing the LOAD switch once This action causes the reel brake solenoids to be energized In this position each of the brake shoes must be in close proximity to the metal washer bonded on the belt pulley but must not be touching If the shoes and washer are too close rubbing will occur during tape movement if they are too far apart
57. prague TL 39D 601D 1000UF 25VDC 00 137 Sprague 500D 6VDC 00 138 Cornell Dubilier NLW 12VDC Capacitors Mylar Film 00 139 FU 210 50VDC 00 140 Type FU 10 100VDC Capacitors Solid Tantalum 00 145 Series 20 00 146 Series E 20 00 147 Series E 20 Diodes 00 021 1N4154 Silicon Diodes Rectifier 00 051p Motorola MDA 952 1 00 045 Motorola 1144001 00 185 _ Motorola 1N4720 plastic case Diodes Zener 00 046 Motorola 155225 3 0V 41065 00 047 Motorola 1N5231 5 1V 10 00 048 Motorola 1N5235 6 8V 10 00 173 Motorola 1N5239 9 1V 10 PART NUMBER CROSS REFERENCE Continued WILLARD LABS MANUFACTURER DESCRIPTION OR PART NUMBER OR EQUIVALENT PART NUMBER IC S SN7476N TTL Dual Motorola MC853P DTL Dual J K FF Motorola MC836P Hex Inverter Motorola MC844P DTL Dual 4 In Power AND Gates Motorola MC4387P Dual Ampl Motorola MC862P DTL Triple 3 In J AND Gates T I SN7416N Hex Inverter Buffers Drivers T SN74123N Dual One Shot Signetics N5558V Dual Ampl Motorola MC846P DTL Quad 2 In AND Gates Motorola MC830P DTL Dual 4 In AND Gates Motorola MC858P DTL Quad 2 AND Power Gates Fairchild UA723C Voltage Regulator Dip Motorola MC856P DTL Dual J K FF Potter Brumfield R10 Ei X4 V185 12VDC 4 Pole Form C 5 Amp 12VDC 185 Ohm Plug In Resistor Carbon Compos
58. qual rise and fall times 9 5 8 Reverse Command REVC This level when it is true and the transport is READY causes the tape to move in reverse at the specified velocity A false level of this command causes tape motion to cease The velocity profile is trapezoidal with nominally equal rise and fall times 220291 Reverse motion of tape will terminate when the BOT tab is reached If the tape is at the load point a REVC true level will be ignored 3 5 4 Rewind Command RWC This is apulse which if the transport is READY causes the tape to move in the reverse direction at 125ips Upon reaching the BOT the rewind ceases and the tape comes to rest at the BOT tab Minimum REWIND COMMAND is 20 3 5 4 1 The REWIND indicator will remain lighted until the tape comes to rest at the BOT 3 5 5 Write Enable Command WEC This signal is a level which must be true a minimum of 208 after the front of a FWDC or a when write mode is required The front edge of the delayed FWDC or REVC is used to sample the WEC signal and set the transport to the write mode If the read mode of operation is required the WEC signal must be false for a minimum of 2005 after the front edge of a FWDC a 3 5 6 Write Data Lines WDP WD0 7 for 9 Channel WDP WD2 7 for 7 Channel These are levels which when true result in a flux transition or logical 1 to be recorded at WRITE DATA STROBE WD
59. r T is present the unit may be placed on line only after the load sequence has been completed FLR is high 4 2 2 1 1 The unit may be placed off line by the signal OFFC but may be placed on line only by the control panel switch If the OFFC sig nalis brought low and if SEL is high see section 4 2 2 2 then the ON LINE flip flop is set and the unit is placed off line 4 5 4 2 2 2 ROS Signal Ready On Line and Selected x An important control signal in the unit is ROS which indicates when the transport is ready on line and selected signal formed at U3A pin 12 will go to a high level when RDY OLN and SEL are all at a high level Operation of the OLN signal has been previously described nation will now be given of the formation of the RDY and SEL terms 4 2 2 2 1 The RDY signal gives an indication that the unit has gone through its load sequence and is not in the rewind mode The inverse signal NRDY is formed at U14A pin 8 and goes low when all four inputs to the gate are high The SEL and SELA signals may assume different states depending on the status of the ISEL and NOLN signals and which optional jumpers are used If jumper W is present SEL goes high if the unit is both selected and on line If jumper Wis not present SEL goes high when the unit is selected When jumper V is used along with jumper W both SEL and go high when the unit is both selected and on line If jumper V is o
60. remove the reel from the hub 3 4 MANUAL CONTROLS The following is a description of the operation of the manual con trols located on the control panel 3 4 1 POWER The POWER switch is an alternate action switch indicator which turns on the power supplies but does not activate the transport 3 4 2 LOAD The LOAD switch is a action switch indicator De pressing this switch for the first time after power has been applied to the 3 1 3 2 unit causes servos to be energized thus giving tape tension De pressing the switch for a second time causes the tape to move to the BOT point The LOAD indicator is lighted when the BOT tab is the photoelectric sensor Figure 3 1 Tape Threading 3 4 3 REWIND The REWIND switch is a momentary switch indicator which may be used only when the unit is off line Depressing this switch causes the tape to rewind to the BOT point Once the BOT point is reached the tab will over shoot the sensor move forward and stop at the load point 3 4 3 1 Depressing REWIND switch when tape is at load point BOT tab under photosensor causes the tape to rewind until ten sion is lost 3 4 4 ON LINE The ON LINE switch is a momentary switch indicator which is enabled after the tape has been brought through its initial load sequence De pressing this switch causes the indicator lamp to light and places the trans port in a state ready to receive e
61. s shown in Figure 2 1 Table 2 1 POWER CONNECTIONS NOMINAL LINEINPUT CONNECT LINE VOLTAGE BETWEEN 115V 1 and 1 230V 1 and 4 2 3 INITIAL CHECKOUT After the transport has been uncrated test the transport controls prior to placing the unit in system operation 2 3 1 The following paragraphs suggest recommended procedure for verifying correct operation of the transport 2 9 4 Connect the power cord and load the tape on the transport as des cribed in paragraph 3 2 2 8 3 Perform the steps outlined on the following pages to verify correct operation of each of the control buttons 2 1 2 NEUTRAL GROUND 115 VAC LINE 2 LINE 3 GROUND 230 VAC Figure 2 1 Wiring Diagram For Power 1 Depress POWER switch to apply transport power 2 Depress the LOAD switch to apply capstan motor and reel motor power Depress LOAD switch momentarily a second time to initiate a load sequence The tape will then move forward until it reaches tab and stops The LOAD indica tor lamp will light when the BOT tab reaches the photo sensor and remain lighted as long as the tab is at the load point No further action will result when the LOAD button is depressed Place the unit on line by pressing the ON LINE switch Observe that the ON LINE indicator lights Place the unit off line by pressing the RESET button and observe that
62. sors 1 1 An error signal then amplified and used to maintain the storage arms in their nominal operating position 1 8 8 Control logic is provided to allow tape once it has been loaded to be brought manually to the load point placed in forward motion rewound and unloaded A reset button allows manual halting of any control command 1 3 4 The logic allows external control of tape motion reading and writing Photoelectric sensors are provided for detecting the beginning of tape BOT tab and the end of tape EOT tab The BOT signal is used internally for control while the EOT signal is transmitted as a level to the customer interface 1 3 5 System interlocks are provided to protect the tape from damage due to component or power failure A disc braking system pre vents tape spillage after loss of power 1 3 6 The data electronics accepts external data signals and write com mands These commands cause information to be recorded in Non Return to Zero format once the tape has been brought up to speed Inter Record Gaps IRG S are provided by the customer controller Data which is read back is presented to the interface along with a strobe signal to indicate that the data is available to be sampled 1 4 POWER REQUIREMENTS The transports operate directly from 115 or 230 volt AC 10 single phase 48 to 440Hz power For power see Table 1 1 1 5 ELECTRICAL AND MECHANICAL SPECIFICATIONS Table 1 1 gives
63. t pin retraction is either too far or not far enough To move the position of the solenoid use an angle wrench to loosen the two cap screws holding the solenoid to its bracket When energized the distance between the plunger nut and the rear of the mounting plate shall be 0 13 01 Retighten the cap screws 5 5 8 Arm Limit Rubber Bumpers Rubber bumpers are provided to cushion the tension arms when they move to their limits Without these rubber bumpers the tension arms would hit against the mounting frame when tape tension is lost 5 95 9 1 These bumpers must be examined periodically to determine if they have worn excessively If so they should be either rotated or changed Rotation involves simply loosening the screw that holds the bum per in place rotating it until the worn section is not facing the arm and tightening the screw To replace the bumper remove the screw washers and spacer and replace with a new bumper WL Part No 00 074 5 9 5 10 APPENDIX WILLARD LABS INC BILL OF MATERIAL RELEASE CHANGE DATE ISSUE o j TITLE TRANSPORT Assy MOD 890815 COMPILED BY DATE CHECKED BY DATE APPROVED BY DATE 5 LEE 11 30 71 NEXT ASSY IST USED ON OF 1 x i 4 DESCRIPTION QTY PART NO REMARKS 7 TRACK WITH FAIL OPTION 20 160 MAY BE USED 20 320 TRANSPORT ASSY BASIC 2 20 31
64. tate if the data is 1 but remain in the pre vious state if the data input is 0 These flip flops then drive the write driver transistors 4 5 2 2 At end of each record parity check characters have to be recorded and an inter record gap inserted Figure 4 4 shows the IBM inter record gap format for 9 and 7 track systems As is shown in this Figure a 9 track system requires both a CRCC and a LRCC character The CRCC is supplied by the customer interface and occurs 4 character times after the last data character The LRCC when required occurs 4 character times after the CRCC and is derived by applying a WRITE 4 10 INTER RECORD T 4 4 0 15 CHAR CHAR SPACES SPACES III I d LRCC FIRST DATA 22 OF PREVIOUS RECORD 9 V INTER RECORD I 4 N CHAR 1 16 HF LRCC A2 LAST DATA E ao CHARACTER CHARACTER PREVIOUS RECORD 7 TRACK Figure 4 4 Inter Record Gap Format For 9 And 7 Tracks 4 11 AMPLIFIER RESET IWARS signal to data electronics This reset signal will cause all write flip flops to reset The result is that an LRCC signal will be written in such a way that the total number of flux transitions on any track is even 4 5 2 9 After the LRCC has been written
65. tch will remain in the Set state until servo supply voltage drops be low a safe operation level causing the latch to be reset and thus permitting another load cycle For a short power failure the latch will be reset by the 14VS which is sensed by V3 C and its input network The 14VS supply is designed to decay very rapidly to zero to ensure that the relay and brake solenoids are deactivated U3 A and U3 B and R8 provide Hysterests Turn on of the unit occurs with a power input of 102VAC typ If the input voltage drops below 95VAC typ the unit will be turned on again if the voltage goes above 102VAC The output of the latch triggers the on line delay circuit R4 C3 At the end of this delay a negative going pulse is generated C4 R5 which turns on the On Line flip flop In the where tape tension can not be established tape not threaded or no tape the tape hubs will rotate approximately one revolution and then stop A manual load operation may then follow optional switch 51 may be vided to permit disabling the power fail restart circuitry Interconnections are made through the following connectors P104 414V to TP4 yellow on the Control PCBA P126 Relay to TP26 blue on the Control PCBA P150 Load to TP59 green on the Control PCBA P105 to 405 On Line on the Control PCBA J105 _ to Control Panel On Line Switch P101 P102 to TB2 1 and solenoid L2 2 black on the pow
66. ter follower which drives a peak detector U22 The peak detector is a differentiator whose output swing is limited by diodes 1CR7 1CR8 1CR9 and 1CR10 When the incoming signal changes from positive to negative the output of the differentiator will swing from negative to positive This swing will cause transistor 1Q4 to saturate The outputs of 1Q4 through 9Q4 are summed to gether through 100K resistors to a test point TP8 Examination of TP8 gives some indication of the relative skew 4 5 3 2 3 negative going output from 104 forms a clock pulse for 1 32 This clock pulse resets the flip flop Q output is inverted through U34 and is the output data to the interface 4 5 3 2 4 The flip flop Q outputs from all 9 channels are ORED together in gate U31 The first data bit to arrive resets its flip flop which in turn causes the output of U31 to go high The output U31 going high causes one one shot U2 to trigger When U2 times out U32 resets causing a 2US pulse to be generated by C5 R25 and R26 This pulse the READ DATA STROBE IRDS indicates to the interface that the data is available to be sampled 4 5 3 2 5 When U32 is reset it not only generates the RDS signal as des cribed previously but a reset signal is also derived 032 pin 8 going low causes U1 8 to go high A delay of greater than 208 is generated by R23 and C4 after which U34 pin 4 goes low This action causes flip flops 032 U33 U35 037 and U38 to
67. this action extinguishes the ON LINE lamp With the transport OFF LINE press the FORWARD button The tape will begin to move forward but no FORWARD lamp willlight Run several feet of tape onto the take up reel and press the RESET button to stop the tape Check that the FORWARD control has no effect if the transport is in the ON LINE mode Press the REVERSE switch tape will begin to move in a reverse direction Prior to the tape reaching the BOT tab press the RESET button to stop the tape motion Again press the REVERSE switch but this time allow the BOT tab to reach the photosensor causing tape motion to halt Check that the REVERSE button has no effect if the trans port is in the ON LINE mode Press the FORWARD switch and allow several feet of tape to advance onto the take up reel Depress the RESET but ton as before to halt forward motion Depress the RE WIND button momentarily to initiate the rewind mode and light the REWIND indicator The tape will rewind past the BOT tab enter the load sequence return to the BOT tab and stop with the LOAD indicator lighted If the REWIND button is momentarily depressed when the tape is at BOT the LOAD indicator will be extinguished the REWIND indicator will be lighted and the tape will re wind until tape tension is lost The tape may then be re moved as described in paragraph 3 3 INTERFACE CONNE CTIONS Customer interface equipment should be connected to the three transp
68. threshold level is automa tically controlled by the write read status of the transport During writing the higher of the two levels is selected while during reading the lower level is selected 3 9 10 Off Line OFFC This is level or pulse of minimum width 2US which causes the transport to be placed under manual control An OFFC signal may be given during rewind but it must be separated by at least 2US from a rewind com 3 5 11 High Density Select HDS Optional This is a level used only in 7 track transports whose true state causes the transport to operate in the higher density mode and causes the HI DEN indicator to be lighted 3 6 INTERFACE OUTPUTS The following is a description of interface signals which are supplied from the transport to the customer controller names pond to the true level of 0 volts Barred terms correspond to a false level which is between 42V and 5V Interface outputs are gated with SELECT 3 6 1 Ready RDYT This is a level which is true only when all of the following condi tions are true tape tension is established the initial load sequence has been completed the transport is on line and no rewind is in progress 5 6 2 Read Data RDP 00 07 9 Channel RDP RD2 RD7 7 Channel These are the individual bits from each data channel assembled into one register The data is ready to be sampled when the READ DATA occurs 3 6 3 Read Data
69. tion of U4C pin 8 The LOAD signal going high causes the forward motion ramp generator to turn on The tape then accelerates up to speed and moves until BOT is sen sed again the RWB and LOAD flip flops are again set and the 110MS BOTD one shot fires At the end of this 110MS period the NRDY signal will go low indicating that the unit is again in a ready state RWA RWB NBOT NBOTD LOAD am PT 7 o tite jg _ NRDY TAPE 12 5 VELOCITY 125 ips Figure 4 3 Waveforms For Rewind To Load Point 4 2 3 2 Tape At The Load Point Unloading Of Tape If the rewind switch is depressed when the tape is at the BOT point it will begin the sequence just previously outlined However since BOT will not be encountered during rewind neither RWB nor LOAD ever go high Hence the tape rewinds until tape tension is lost An external re wind command will have no effect if the tape is already at BOT Therefore it is impossible to unload tape from an external command 4 3 0 0 POWER SUPPLY The power supply consists of two unregulated voltages 14V and 14V two regulated voltages 5V and 5V and an unregulated auxiliary voltage of approximately 15V Depressing the POWER switch applies AC 4 8 power to the transformer primary and lights lamp The secondary voltage is rectified with bridge CR1 and filtered with C1
70. vice versa 5 9 1 2 To insert the shims first remove the guide retaining screw and remove the guide Place onto the screw the proper number of one half of a thousandth WL Part No 00 082 shims The proper number of shims is calculated as follows Determine the spacing between characters on the tape according to the expression S 1 Density 5 5 1 3 For example the spacing at 800BPI is 1250Uinches If example skew measurements at TP8 show the magnitude of skew tobe 1 6th of the period of the waveform then the skew is approximately 20808 A ratio of about 10 to 1 should be used in determining the number of shims to be used at the guides Thus in the above example shimming should move 5 4 the guide 2080Uinches or 5 500 Uinch shims should be used Note that these calculations are approximate because of the difference in distance between the right guide and the head and the left guide and the head A certain amount of experimentation is required to arrive at the final number of shims required Pari JHT A IDEAL SKEW WAVEFORM B POOR SKEW WAVEFORM Figure 5 1 Skew Waveforms 5 5 5 5 2 Replacement Of The Precision Magnetic Head And Drive Assembly The magnetic head requires replacement if it or the cable is defec tive or if the head has worn considerably As a rule of thumb head wear is _ considered excessive if the worn section of the head crown is greater than 0 010 inch below the un
71. worn section Also the head should be replaced if deep grooves appear on the crown of the head 5 5 2 1 The entire precision magnetic head and drive assembly may be re replaced easily without any requirement for head deskew adjust ments To replace this assembly first remove the head connector and cable clamp from the data electronics board Remove the three cap screws holding the precision plate to the mounting plate Remove the precision plate while carefully bringing the head through the hole in the mounting plate Position the new precision plate and head assembly in place and replace the three cap screws The head will now bein correct position with no further mechanical adjustments required 5 5 2 2 As an alternative head itself may be replaced thus requiring shimming for deskew adjustment To replace the head remove the head cover if supplied and unplug the cable connector from the data board Disconnect the cable clamp Next remove the screws that hold the head in place and bring the connector through the hole in the mounting plate Bring the connector of the new cable through the same hole and attach it to its mating section on the data board Fasten new head in place with two mounting screws Attach the cable clamp Reel Servo Belt Tension The belts which connect the reel hubs to the servo motors must be adjusted to a proper tension This tension must be sufficient to prevent belt teeth from ski
72. xternal commands Depressing the RESET SWITCH causes the lamp to be extinguished and the transport to revert to the off line mode The transport will also switch to the off line mode if an nal off line command is given or if the tape tension is lost In the off line mode control commands are accepted only from the control panel switches 3 4 5 WRT EN Write Enable WRT EN is an indicator lamp which is lighted when a reel with a write enable ring is installed on the supply reel hub 3 4 6 HI DEN High Density Optional The HI DEN switch is an alternate action switch indicator which is provided only in the 7 track transports where there is a choice of two dif ferent densities of recording When the indicator is lighted the higher of the two densities is selected when the indicator is extinguished the lower of the two densities is selected 3 4 6 1 An optional feature of 7 track transports allows customer to use external high density commands When this option is selected a HI DEN indicator is provided with no corresponding control panel switch 3 4 7 Forward motion of the tape results from depressing momen tary FORWARD switch This switch is enabled only in the off line mode of operation and has no lamp associated with it Motion will cease if the EOT tab is encountered or if the RESET switch is depressed 3 4 8 REVERSE Reverse motion of the tape results from depressing the momen tary
73. y U3C pin 4 and 03 pin 2 4 2 2 3 2 Density selection is controlled by an external command or an external pushbutton if included For 9 channel transports there is one density and therefore no selection is provided In this case jumper U1 U2 is included causing NHID to be permanently low and IHDI to be low when the transport is selected For 7 channel transports two densities are available For external density selection in these transports jumper 01 U3 is included but jumper U1 U2 is omitted an alternative high den sity selection may be performed with an alternate action pushbutton in 4 6 which case jumper is included and external selection through U1 U3 is usually omitted Whenever NHID is low the high density lamp is lighted 4 2 2 3 3 If writing is to be performed a write enable ring must be placed in the reel prior to placing it on the transport With this ring in place the signal WRT PWR goes high after the LOAD switch is depressed for the first time see paragraph 4 2 1 2 With this signal high 08 pin 10 is brought low thus enabling the write enable lamp driver In addition the file protect signal IFPI goes high when the unit is selected 4 2 2 4 Operation From The Control Panel When the transport is placed in the off line mode it is ready to receive commands from the control panel switches If the transport is both ready and off line U2A 5 is high Depressing the FORWARD switch will cause U2

OPERA TING AND SERVICE MANUAL WILLARD MODELS 87XX1

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