[Today’s run: rest day]
I worked a bit more on that homebrew 13-tube HF receiver that I picked up at the Jackson hamfest.
With much help from the “boatanchors” forum on eham.net, I now have it working, in a manner of speaking.
After getting some help with figuring out what the IF frequencies were (1415 kHz and 85 kHz), I was able to hook up a signal generator and tune in part of 40 meters. I also discovered that hi-z headphones were required. Then I noticed that the LO was inoperative because the tube base wiring did not fit the tube in that socket. Back to the forum, and I now have a 6C4 in that socket and the LO is working. So, we have a receiver!
There are still quite a few problems with it. I think all of the large caps will need replaced. The multi-part power supply cap is leaking brown fluid and there are other wax and “black beauty” caps that are known points of failure. Then it will need some attention in the rf-gain control (if cap replacement doesn’t fix it). Right now it is only configured to cover the sideband portions of 80/40/20 meters. Not really my usual stomping grounds. I could adjust it to cover the CW sub-bands instead. And the bandswitch/tuning mechanism needs some mechanical help. Finally, the only T/R provision that I can find is a relay which disconnects the external speaker. That seems pretty bogus! (Maybe there is more to it that I have not yet discovered.)
I’m not really sure what should happen next. Maybe I’ll make a list of caps to replace and see what that task looks like. I may just put it on the shelf.
