[ARC5] BC-453 drift

[J Mcvey]

Still trying to get a handle on the drift problem.I disconnected the lower bleeder/bias resistor (R23) and installed a Zener stack that added up to 109V.
The radio sound OK on CW, but has an almost imperceptible slow drift to higher audio frequency on the WJST-x waterfall. It's more pronounced on WJST-x because the waterfall is very slow, so it shows the drift over time better.Doesn't look bad on FL digi, but if you notice where you start and where you are in 10 minutes, there is quite a spread.
In 15 minutes it went from 1050 Hz to almost 1400 HZ and doesn't seem to be slowing down.I used a beacon with a reasonably strong signal to do the tracking.I zero-beated the signal at 1050 then watched the drift. When I turned the BFO off, the audio was still at 1050.The beacon is AM , so I guess the IF's would still be broad enough to compensate for the front end drift?If the BW is say, 1000 HZ, a 400 hz shift in the LO should start degrading the signal-right? The signal sounds steady and when I fiddled with the tuning , It could not make it batter than it already  was. I think the bigger issue may be the BFO.
I'm trying figure out if it's the BFO or the LO- or both...but it ain't easy!
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