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1935 38B radio
#8

I've built these supplies using an LM338T regulator which is rated at 5A, and comes in a TO-220 package. Yes, I know, 5A is overkill for the Model 38...but the TO-220 came in quite handy in terms of size reduction and operating temperature. Clip a heatsink on top and it is good to go. When powering a Model 38, it runs warm instead of red hot as an LM317 would.

I had to build one of these power supplies INTO the chassis of a Model 38 once for a client. Worked out quite well. I had to mount the power transformer on top of the chassis where the unused Type 6 ballast socket was (removing that socket to allow space for the transformer wires to pass through), and a perfboard with the power supply components directly underneath.

I'll scan the schematic of my design later today and post here.

--
Ron Ramirez
Ferdinand IN


Messages In This Thread
1935 38B radio - by Chris Drumma - 11-09-2006, 08:54 AM
[No subject] - by Ron Ramirez - 11-09-2006, 09:31 AM
[No subject] - by Chris Drumma - 11-09-2006, 10:12 AM
[No subject] - by Ron Ramirez - 11-09-2006, 10:32 AM
[No subject] - by Bill Hutchinson - 11-09-2006, 09:17 PM
[No subject] - by Chuck Schwark - 11-09-2006, 10:24 PM
[No subject] - by Bill Hutchinson - 11-09-2006, 11:08 PM
[No subject] - by Ron Ramirez - 11-10-2006, 11:05 AM
[No subject] - by Ron Ramirez - 11-10-2006, 11:11 PM



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