General-Electric-Co-P800A 电路原理图.pdf

VOLUME R-20, MOST-OFTEN-NEEDED 1960 RADIO SERVICING INFORMATION GENERAL ELECTRIC Model P800A TROUBLESHOOTING TO REMOVE CIRCUIT BOARD 1. Remove cabinet back. 2. Remove hex-head screws holding chassis board to cabinet front. Caution: Do not remove brass hex-head screws holding speaker magnets to speaker. TO REMOVE TUNING CAPACITOR OR VOLUME CONTROL 1. Remove knobs. 2. Remove cabinet back. 3. Remove chassis. 4. Remove flat head screw from cabinet front. a) To replace tuning capacitor, remove phillips head screws on cabinet front. b) To replace volume control, remove screw from bracket near volume control inside cabinet front. NO RECEPTION: 1. Check battery voltage and battery contacts. 2. Check on-off switch. 3. Check all antenna lead connections. 4. Check coil L2. WEAK AUDIO: 1. Check battery voltage for 6 volts. 2. Check battery current. 3. Check transistor collector currents. 4. Check alignment. INTERMITTENT: 1. Check battery contacts for corrosion. 2. Check solder connections on dip-soldered side of circuit board. Intermittent audio, motorboating, and poor re ception is frequently caused by poor battery con tact or low battery voltage. The terminals on the batteries should be cleaned to insure positive electrical contact. IF TRANSFORMER IF TRANSFORMERS OSCILLATOR TRANSISTOR 1ST 2ND IF 8 3RD iF COIL MOUNTING ALIGNMENT SET VOLUME CONTROL AT MAXIMUM CONNECT OUTPUT METER OR SCOPE ACROSS VOICE COIL INDUCTIVELY COUPLE SIGNAL GENERATOR TO RECEIVER STEP 1,2,83-SET SIG GEN AT 455KC. WITH RECEIVER TUNING GANG OPEN STEP 4 - SET SIG GEN AT I620KC, WITH RECEIVER TUNING GANG OPEN STEP 5-SET SIG GEN AT I400KC. STEP 6- SET SIG GEN AT 580KC NOTES 1 UNLESS OTHERWISE NOTED-CAPACITORS MORE THAN I =MMF CAPACITORS LESS THAN I = MF RESISTORS ARE WATT K* 1000 2 REPLACE WITH TRANSISTOR TYPES SHOWN BOTTOM VIEWS TO SPKR C * 1 sAAr-J lO / lA vJ TUN ING CAPACITOR Mr Mr 60 收音机爱 好者资料库 RadioFans.CN