'49 Admiral audio problem

[kbmuri]

All,

I'm hopefully finishing up a 1949 Admiral chassis 20B1 (Sams sheet 77-1) shortly. Complete recap, all electrolytics and wax paper caps are new. All tubes are NOS or test as such. Since these photos were taken I've centered and shrunk the picture height so that it's the classic double-D shape. The vertical linearity is set very well. Horizontal linearity is still just a tad off (you can see a drive-line just to the left of Daria's lamp -- but that's beside the point just now). The picture is rock-solid and the focus, contrast and brightness work smoothly and correctly. Channels 3 and 4 work as advertised, that's all I can test with what I've got for video sources (No VHF stations nearby).

When I run my signal generator and inductively couple the output to the TV's antenna terminals (just place the coax nearby), I can tune in very crisp horizontal bars, as shown. Tuning the signal generator to a slightly higher frequency results in fuzzy bars, and a very clear, loud tone from the speaker. If I turn the volume control up, the tone is loud to the point of risking damage to the speaker (and my eardrums). I'm convinced the audio amp circuits are golden.

When I run a VCR thru the set, matched-transformer-coupled from the VCR's coax to the antenna terminals, I get a great picture but no sound at all. Adjusting the TV's fine-tuning has no effect on the audio, normal effect on the video. If I unscrew the sound-IF coil slugs (A2 and A5 of L18 and L19) to what seems like an unreasonable distance outward, I get very minimal audio (volume control all the way up, still too muffled for comfortable listening in a quiet room, and the fair amount of hiss and a little 60Hz hum that you would expect with the volume control all the way up). This is the best I can do, regardless of where I set any other adjustments anywhere else on the chassis. I'm a little stumped at this point.

Anybody out there been through this? Any suggestions? Thanks.