I've got the video rock solid on this set but still no audio
All I get is static which does increase with the volume control. I can also touch the volume control wiper and I get a hum. I've gone over the audio IF stages pretty thoroughly, so I decided to try aligning it by following these instructions:
Here's the gear I used. A 3 AAs soldered together for the -4.5v AGC bias voltage. An EICO 232 VTVM and a Hickock 615 sweep and marker generator. Finally, an HP 45600B scope and demodulator probe.
I think I did everything correctly. Here's the ratio detector response curve, but still no audio
Just a buzz that occurs when bright white portions appear in the video.
I know it's backwards, but I think that's just the nature of my sweep generator / scope - the key points match up more or less.
Any ideas ? I bet it's something really stupid!