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BC-348 Power Supply
#4

I've had one or two (BC-348's) over the yrs but it's been a long time ago. Here's a good starting point https://www.radioblvd.com/bc-348_dynamotor_part3.htm I don't remember if you have to rewire the heater circuit to make it usable at 6.3v vs it's normal 24vdc. That's a common thing with WWII aircraft set like the command set SCR-274N/ARC-5 that were dynamotor powered.

If you can find a pt that can make 250vdc at 60 or 70ma + a 24v transformer to power the heaters that's a good start. The rest is just some caps, diodes, and resistors. If you have some room a choke is always a good think to filter the hum out.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry


Messages In This Thread
BC-348 Power Supply - by galaxybeing - 11-29-2023, 04:02 PM
RE: BC-348 Power Supply - by Chas - 11-29-2023, 07:25 PM
RE: BC-348 Power Supply - by galaxybeing - 11-29-2023, 08:48 PM
RE: BC-348 Power Supply - by Radioroslyn - 11-29-2023, 09:45 PM
RE: BC-348 Power Supply - by Chas - 11-29-2023, 11:16 PM
RE: BC-348 Power Supply - by galaxybeing - 11-29-2023, 11:27 PM
RE: BC-348 Power Supply - by Radioroslyn - 11-30-2023, 11:24 AM



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