Labels:text | font | black and white | diagram | screenshot | white OCR: CHANNEL 68 DECODER BLOCK DIAGRAM TAP UHF MAST - MOUNT VIDEO AMPLIFIER AM P 750 733 VHF TV AUDIO RECEIVER UMF VARACTOR TUNER VIDEO DETECTED 733 AUDIO 00 OUT AGC FALL 1980 NO.64 PULSE SYNC 5. 738 KHZ GEN MODULE IPEAN PEAK/ NOTCH 741 74221 311 FILTER PRE- AMP NOTCH Pre-Amp Module - PIN 1 NULL CIRCUIT: - V 310K FREQUENCY HIGH - PINS DOUBLER PASS FILTER 10K 300 MV IK INPUTO (5 10 500 mV) 741 0 OUTPUT PRODUCT IK + 10 mg DETECTOR 300 mV 1 +v Video Amp LOW AUDIO Oscillations appear at higher gains of AGC, PASS FILTER OUT (around -2 volts to the gate). Try to control the loading with this circuiti Low Pass Filter TEV -CV +6V Fco = 12 KHZ 382 0 10 1 40317 - Q = 25 733 1000 FF 7512 OUT Gain = 1 R2 3300 - FV R3 66K 20 PF 20k 1/4 Vca 20K 1 FROM 0 AUDIO PROD I . 01 3900 OUT 2N4392 DET. Vc= - 2 to -15. G ...
