08-31-2020, 06:07 PM
This set has been languishing here since '12. I got from an ebay seller and the price was good. And from what I remembered it was in good shape. About that time it was a busy time for me so it ended up in my shed unopened. Since I've been waiting on some parts for the 16B2, might be a good time to have a look at the 370.
Dug it out drug it inside. Opened it up to find it had two broken legs. Must of happened in transit but fortunately a bit of gluing and clamping did the trick to put it right.
Chassis was dirty but unmolested, should be able to get it going in a day or so. Did the b blocks (only abt 6 of them) caps in tins, and soldered in a couple of new filter caps. This one has the silver screw in type which I don't have a large pipe cutter to rebuild them properly. Two or three resistors there were off. Tuning cap's supports were shot made some new one with a few grommets. To install the cap had to come off it got a quick clean and new wires. New AC cord and time to give it a whirl.
No smoke or fire but no signal either. Set the signal generator to 260kc and got a weak signal. turned up the volume control and found the issue. It was either barely any signal or full blast. Bad 250 ohm section in the dual section control. The 5000 ohm section was fine. The 370 uses this dual control which is identical to the other pre avc model 70s, model 20, and 21. But it has an off/on switch activated at fully clockwise.
Found a 500/5000ohm dual pot which which should be a good match. Installed it and added a micro switch to replace the off/on switch. Didn't want to use one of those in line jobs.
Much easier to align when you can turn down the rf and IF gain. The IF is kinda squirrelly wanting to break into oscillation when adjusted. For now it's behaving (playing for four hours) and it will be going back in to its cabinet. Wasn't bad about two and a half days.
Weather here in Pa has been very humid for the most part so not sure when I'll get to the woodwork.
Dug it out drug it inside. Opened it up to find it had two broken legs. Must of happened in transit but fortunately a bit of gluing and clamping did the trick to put it right.
Chassis was dirty but unmolested, should be able to get it going in a day or so. Did the b blocks (only abt 6 of them) caps in tins, and soldered in a couple of new filter caps. This one has the silver screw in type which I don't have a large pipe cutter to rebuild them properly. Two or three resistors there were off. Tuning cap's supports were shot made some new one with a few grommets. To install the cap had to come off it got a quick clean and new wires. New AC cord and time to give it a whirl.
No smoke or fire but no signal either. Set the signal generator to 260kc and got a weak signal. turned up the volume control and found the issue. It was either barely any signal or full blast. Bad 250 ohm section in the dual section control. The 5000 ohm section was fine. The 370 uses this dual control which is identical to the other pre avc model 70s, model 20, and 21. But it has an off/on switch activated at fully clockwise.
Found a 500/5000ohm dual pot which which should be a good match. Installed it and added a micro switch to replace the off/on switch. Didn't want to use one of those in line jobs.
Much easier to align when you can turn down the rf and IF gain. The IF is kinda squirrelly wanting to break into oscillation when adjusted. For now it's behaving (playing for four hours) and it will be going back in to its cabinet. Wasn't bad about two and a half days.
Weather here in Pa has been very humid for the most part so not sure when I'll get to the woodwork.