[Hallicrafters] S-38 knob needed & another BFO query

[Craig Roberts]

Hiya fellas,

I'm in need of an S-38-series main tuning knob. If you have one, as they say, "surplus to your needs", please contact me.

And then there's my continuing and mysterious S-38 BFO problem. It's become a matter of principle that I fix this thing. This is a first-series '38 with the separate BFO pitch control and extra 12SQ7 BFO/noise limiter tube.  I've now got it oscillating after a fashion, but it's only apparent at very low incoming signal levels (using a very short antenna or none at all).  Strong signals overpower the beat note.  Any ideas?  

Also, on the old, original model S-38, where does the common ground lead from the multi-section capacitor go?  My receiver power supply circuit was gutted when I obtained it, so I can't trace the original. I've recapped it using individual electrolytics and grounded them to the chassis, but I'm getting a low-level hum. The ground points on my later S-38-series sets vary (the '38C uses a floating ground, for instance), so I get no guidance there.  

Many thanks again,

Craig
W3CRR