Weak antenna input = strong sound and vice versa

[bandersen]

I think I've solved my audio issues

First up , I removed the old micas and installed new ones. That improved the sound quite a bit.




Then, I made a properly terminated (90 ohm non-inductive) probe for my Hickok 615 generator and realigned the audio IF. That improved the sound even more.


Finally, for a signal source I used a DTV receiver feeding into an BT modulator. The low-level test output of that went to the TVs antenna terminals via a 75-300 balun. If I use the RF output of the DTV box directly, I get almost no sound at all!

Luckily, we do still have one LP VHF analog broadcast in my area. I can just use a two foot scrap of wire for an antenna and get excellent sound levels now! So I figure the DTV box is at fault here even though it sounds OK when plugged into a more modern TV.


Next up, I'm going to move the chassis into another room where I can plug it into cable TV.