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Transformer replacement
#1

My 42-1008 transformer was shorted. I am attempting to replace it with a similar one from a 40-185, which has similar power and # tubes. The only issue is that the 42-1008 has about 12 wires, and this one only has 6 or 7. For example, the rectifier wires are only 2 on the new transformer, but there were 4 on the old. Is there a way to make this work?
#2

This transformer is not the best candidate to be a replacement.

For starters the 84 tube in it sits on the same filament voltage which is 6.3V.
However the 5Y4 is a 5V filament tube.

Of course you could replace the tube with a 6.3V rectifier but then you start looking into things like is the tube adequate etc.
Also you have to account for the 6.3V filament winding on the new transformer being capable of the current it requires to run all the tubes now. Plus the pilot lamps.
And of course the rectifier voltage winding itself, you have to make sure it is adequate both in voltage and the ampacity.
#3

I was able to locate a used Hammond 272JX, which is 300V, 250 MA which looks like it may work, can someone confirm for me? It has almost the same specs as the 272X which RadioDaze told me was a suitable replacement, but the 272x has 620v Any comments are appreciated.
#4

250ma is an awful lot of current for your set. Probably only need 80-90ma tops. Voltage sounds ok. The size is going to be kinda big I would think.
Terry




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