![A85 amplifier - power output stage left](/images/new-backgrounds/27367/2736723x1.webp)
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D |
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| VPOS |
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| R319 |
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| 100R SM |
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| R315 |
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| R316 |
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| R300 |
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| 100R SM |
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| 100R SM |
| PRE DRIVER |
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| 10K SM |
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| PNP CURRENT MIRROR |
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| TR310 |
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| TR300 |
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| TR301 |
| FMMT497 |
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| FMMT597 |
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| FMMT597 |
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| R301 |
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| 10K SM |
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C300 | DZ300 |
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| R321 |
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| TR302 |
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100U EL | 15V 350MW SM |
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| TR309 | 22R SM |
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| FMMT597 |
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| TR321 | FMMT497 |
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| FMMT597 | R338 |
| OUTPUT STAGE |
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| R329 | R305 | VI PROTECT |
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| C307 |
| 150R SM |
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| D301 |
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| 4K7 SM | 10K SM | SIGNAL TO MICRO |
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| TP307 |
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0V_HF |
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| R333 |
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| TR318 |
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| R334 | BAS16W SM |
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| VIPROT |
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| 3K3 SM |
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| SAP15N |
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| 22K SM |
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| TR311 |
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| 100P SM |
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| R306 | + C305 | DZ305 |
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| C317 |
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| TP305 | R341 |
| TR312 | D303 |
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| TR313 |
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| FMMT497 | DC SERVO |
| BOOTSTRAP |
| R347 | R349 |
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| 10K SM | 10U EL | 4V7 350MW SM |
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| 330R SM | FMMT497 | 1N4003F |
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| FMMT497 |
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| 100R SM |
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| 100R SM |
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| + C302 |
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| 470N PE |
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| R325 |
| R343 | R345 |
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| C310 |
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| IC300B |
| 6R330 |
| 100U EL 100V | ADJ BIAS | 1K0 SM |
| 100R SM | 0R0 SM |
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| 100N SM |
| 7 |
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| 0V_HF |
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| 1M0 SM |
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| + C303 |
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| 0V_SIG |
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| RV300 | R340 | 1 | PL300 |
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| R328 | TL072CD | 0V_SIG |
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| 100U EL |
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| 100R PSET | 100K SM | 2 |
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| 4K7 SM |
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| R352 |
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| R351 |
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C |
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| TP302 |
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| R331 |
| 470R 2W MF 5% | D300 |
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| MEASURE |
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| 10R MF |
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| C |
INPUT FILTER | V TO I AMP |
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8 |
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| BAS16W SM |
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| BIAS |
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| 0V_SIG |
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| 1K5 SM |
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| L300 |
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| R324 |
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| (SET TO 16mV) |
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INPUT | 3 |
| IC300A |
| TP304 |
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| OUTPUT |
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| R332 |
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1K0 SM |
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| 470R 2W MF 5% |
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| 2U2H LAC SMALL |
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| 2 |
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| DC OFFSET SIGNAL |
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DZ302 |
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| 1K8 SM |
| R353 |
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4V7 350MW SM |
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| TL072CD |
| R322 |
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| TO MICRO |
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| R327 |
| 4 |
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| 22R SM |
| R355 |
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| DCPROT |
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| R350 |
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| 22K SM |
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| R303 |
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| 5R6 2W CF |
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| 6K8 SM | + C318 |
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| + C304 |
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| TR322 |
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| 10K SM |
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DZ303 | C316 |
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| C312 |
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| ZOBEL NETWORK |
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| R337 | FMMT497 |
| 10U EL |
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| 100U EL |
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| TR305 |
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4V7 350MW SM | 470P PPW |
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| C311 |
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| 10N SM |
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| DC OFFSET |
| C319 |
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| 22R SM |
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| FMMT597 |
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0V_SIG |
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| 100N PC |
| + C306 |
| R326 |
| R344 | R346 |
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| R304 | DETECTION |
| 100N PE |
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| TP303 |
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| R354 |
| 1K0 SM |
| 100R SM | 0R0 SM |
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| 10K SM |
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| C313 |
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0V_SIG | C309 |
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| TR304 |
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| 0V_SIG |
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| 1K0 SM | 100U EL 100V |
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| R348 | D304 |
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| R308 |
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| 0V_LS |
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| 100N SM |
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| BOOTSTRAP |
| TP306 | R342 | FMMT597 |
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| 0V_HF |
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| TR303 |
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| 100R SM |
| 1N4003F |
| R302 |
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| 22K SM |
| 100N SM |
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| FMMT597 |
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| 330R SM |
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| 10K SM |
| R307 |
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| 0V_HF |
| 0V_LS |
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| 10K SM |
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| C308 |
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| R336 |
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| TP308 |
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| C314 |
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| R335 |
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| TR319 |
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| 22K SM | D302 |
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| TR316 |
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| 100N SM |
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| 3K3 SM |
| R339 |
| SAP15P |
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| BAS16W SM |
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| FMMT497 |
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| 0V_SIG |
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| 100P SM |
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| DZ306 |
| R310 |
| R313 |
| C320 |
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| DZ301 |
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| TR320 | 150R SM |
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| R314 |
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| FMMT497 |
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| OUTPUT STAGE |
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| 4V7 350MW SM | 4K7 SM |
| 10K SM | 100U NP | 10K SM |
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+ | 15V 350MW SM |
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| C315 |
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0V_HF |
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| TR306 | R323 |
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| 100N SM |
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C301 |
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| 0V_HF |
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100U EL |
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| FMMT597 | 22R SM |
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| 0V_HF |
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| TR314 |
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| TR315 |
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| R309 | FMMT497 |
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| FMMT497 |
| TR307 |
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| 10K SM |
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| FMMT597 |
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| TR308 |
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| NPN CURRENT MIRROR |
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| PRE DRIVER |
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| FMMT597 |
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B |
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| 10K SM |
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| B |
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| R312 | FMMT497 |
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A |
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| A |
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| 01_1101 | JR | 6/4/01 | POWER SUPPLY FUSES AND DC OFFSET | 3.2 | ||
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| DRAWING TITLE |
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| 00_1134 | MGM | 17/11/00 NO CHANGE TO THIS SHEET |
| 2.4 | ||
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| A85 amplifier - power output stage left |
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| 00_1138 | JR | 27/11/00 C303 C304 FROM 10U TO 100U |
| 2.3 | |||||
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| 23425 |
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| Circuit Diagram |
| 00_1129 | JR | 1/11/00 R345 R346 C307 C308 VALUE CHANGES | 2.2 | ||||
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| Notes: |
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| 00_1115 | JR | 16/10/00 R338 R339 CHANGED TO 150R |
| 2.1 | |||
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| A & R Cambridge Ltd. |
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| Pembroke Avenue |
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| 00_1086 | JR | 19/9/00 NO CHANGE TO THIS SHEET |
| 2.0 | ||
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| Denny Industrial Centre |
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| ECO No. | INITIALS | DATE |
| DESCRIPTION OF CHANGE | ISSUE | |
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| Waterbeach |
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| Filename |
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| Date Printed |
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| Drawn by: | Sheet 3 of 4 |
| L882C3 | |
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| Cambridge CB5 9PB |
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| DRAWING NO. | ||||||
1 |
| 2 |
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| 3 |
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| 4 |
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| 5 |
| L882C3_3.2.SCH |
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| J Reckless | ||||||
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| 6 |
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| 7 |
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