[TinCanAlley]

Originally Posted by old_tv_nut

1) If the DC voltage is 6.99, that is the average of the video waveform, that is, the high parts of the waveform are more than 6.99 V, and the low parts (sync pulses) are less than 6.99. The difference between the max and min is 1.4.

2) The gated rainbow pattern does not go to full white level, so it's peak-to-peak range would be less than a test signal containing full whites. Does the service info say what test signal is used to get the 1.4 volts?

3) Having 2 volts p-p could be from an AGC misadjustment, but before jumping to conclusions, how does the picture look? Overly bright and unstable, or OK?

I used the gated rainbow to have a stable waveform using RF, but when I tested the composite insertion on C1, I used a DVD playing video. What I got was way too low brightness and no sync. I did that with the IF removed, so today I plan on trying it again with the IF installed, but the tuner lead disconnected.

I believe the lack of brightness and sync was due to the IF module being removed. The chroma module input being fed from the IF module is also 6.99V and it probably couldn't compensate for the 4V with the module removed. The sync going to the video module is 6.24V and that one also didn't like the lower voltage with the IF removed.

I haven't adjusted the AGC since it said to do it with a weak channel, without snow. If I do it, the signal I feed it will not be weak and the adjustment will be off, or so I believe.