04-17-2013, 04:06 PM
It appears I have a self oscillation in the output, however it is inaudible. If I turn the volume all the way down, it shows on the scope as a steady pattern. I measured it at ~18kcs with my counter. No change in amplitude with the audio pot. It remains superimposed on incomming audio at the speaker.
If I unplug the first audio tube, it changes slightly, but still there and occurs on all three bands.
Otherwise audio from stations is coming through, but I suspect it is mixing with the normal audio and might introduce some sort of distortion. All caps in the output are (new and tested) polyester or polypropilene orange drops.
Any suggestions from the experts where to look for this?
Thanks,
Brian
If I unplug the first audio tube, it changes slightly, but still there and occurs on all three bands.
Otherwise audio from stations is coming through, but I suspect it is mixing with the normal audio and might introduce some sort of distortion. All caps in the output are (new and tested) polyester or polypropilene orange drops.
Any suggestions from the experts where to look for this?
Thanks,
Brian