Galvin-Mfg-Co（Motorola）-HS-981 电路原理图.pdf
VOLUME R-23, MOST-OFTEN-NEEDED 1963 RADIO SERVICING INFORMATION MOTOROLA A2,MISERIES Chassis HS-939, HS-981 C21fC22,C23 SERIES 12AV6 DET-AVC-AF AMP R1 22K |2 Birr 1l2 iSiffi iLxy - ,JC 3? * I - -vXiii)X (C21 C22 C23 ONLY) - E4 JCLOCK 1 + A + C6A C68 30MF 50MF CHASSIS REMOVAL MODELS A21, AZZ 1. Remove cabinet back - 4 screws hold it in place. 2. Remove chassis mtg. screw at base of chassis and screw at tuning gang mtg bracket. 3. Pull off volume knob ONLY. (Do not pull captivated tuning knob). 4. From front, unscrew palnut under volume control knob. 5. Unsolder appropriate leads to slide chassis out of tuning knob and cabinet. ON OFF SW ON VOL CONTVC (A21 it A22 ONLY) 50C5 128A6 128E6 I2AV6 XL,3(A21 & A22) MODELS A21,A22,C21,C22,C23 SCHEMATIC DIAGRAM MODELS C2l, C22, C23 1. Remove cabinet back - 2 screws hold it in place. 2. Pull off volume and tuning knobs. 3. From rear, remove chassis mtg. screw located on volume control mounting bracket. 4. Unsolder appropriate leads to slide chassis from cabinet. MODELS A21 SA22 NOTES: CAPACITORS - UNLESS OTHERWISE SPECIFIED DECIMAL VALUES IN MF, ALL OTHERS IN MMF. VOLTAGES - MEASURED FROM POINT INDICATED TO CHASSIS WITH A VTVM. 10% NO SIGNAL INPUT TUNING RANGE - 535KC TO I62QKC IIF - 455KC) PLATED 80ARDWIRING LEGEND A-8+ _t =AVC -FIL 3 SHIELD L2 CONN TI&T2C0NN -r-o BOT VIEW BOT VIEW ALIGNMENT DETAILS MODELS 021,22 8 23 ALIGNMENT Use an isolation transformer between the power line and the receiver. If not available, connect low side of generator to B- through a .1 mf capacitor. Connect a low range output meter across speaker voice coil and set volume control to maximum. Attenuate generator output to maintain 50 milliwatts on output meter to prevent overloading (50 milliwatts is .64 volts across 8 ohm load). (GENERATOR CONNECTION IF ALIGNMENT 1. Grid of conv (pin 7, 12BE6) thru .1 mf & B- GENERATOR FREQUENCY (400 cycle mod) GANG SETTING Fully open ADJUST REMARKS 1,2,3 & 4 I Adjust for maximum. RF ALIGNMENT 2. I Grid of conv (pin 7, I 12BE6) thru .1 mf & B- Fully open Adjust for maximum. 87 收音机爱 好者资料库 RadioFans.CN
