I do have a vexing issue still with the AGC that I don't understand. Originally I had no AGC voltage at all. After changing the two AGC diodes and both gate and amp transistors I do have voltage of 3-6 volts depending on AGC control setting. BUT there's an 8 volt zener that spills voltage into the tuner AGC line and I never get voltage that high. A high signal input from the test equip. increases voltage from 5.5 to 6 volts, that's it. BUT the schematic calls for around 5.5 normal with signal so I'm not sure what's right. The service manual for similar models says I should be able to get 2-14 volts....
Pulses controlling the AGC gate from the coil on the new flyback are weak on the positive side through the diode but strong on the negative side....
Last edited by Hagstar; 02-24-2017 at 07:49 PM.
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