Re: R209 - BFO injection
The R209 is a bit strange: there's no AGC operating on CW; instead a squidge of the BFO's output is tapped off, fed to the diode in the 1S5 BFO-valve and rectified - this then provides the negative bias-voltage to feed [via the second gang of the 'gain' control] to the grids of the RF/IF amps to provide manual gain control.
If you have what sounds to me like low BFO-injection and gain-control issues I'd check the BFO valve, as if this isn't producing enough output you'll lack BFO injection as well as adequate bias.
Another thing to check: the R209s of my acquaintance make use of some strange decoupling capacitors with a grey rubbery outer-jacket. These are replace-on-sight, in the same spirit as Hunts and Waxies. Leakage here can cause significant issues.
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