Buzz in sound from video - a porthole

[old_coot88]

First of all, reduce the input signal to a level that's consistent with a snow-free picture. Adjust AGC for good contrast with no sync tear.

Adjust the quadrature (sound detector) coil L64 in conjunction with the buzz control for minimum buzz. You may have to juggle them a few times.
The IF input coil L63 may need a slight peaking for best volume.

The L64/buzz control adjustments are quite critical and may need re-tweaking as the set warms up, so set them with the set warm.