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majestic 620 power transformer
5/26/2007 5:13:50 PMkris
One further question about this radio, when running it the power transformer gets to about 130 degrees, when run without the rectifier it is about 110 in the same 30 min time frame. Both the rectifier and the output tube are very close to the transformer, is this too hot or just a symptom from this style of radio it never smells bad, pops, or shows signs of previous overheating and the radio runs well.
5/26/2007 10:19:19 PMNorm Leal
Hi Kris

Transformer at 130 degrees is ok, as long as that's F. A transformer operated on a hot day will be higher temperature than on a cold day. Transformers are rated for temperature rise. Usually rated for a 40 or 45 degree C rise.

Hopefully you replaced electrolytic filter caps and others if leaky. Bad caps will cause excessive current to be drawn and transformer heating.

Norm

:One further question about this radio, when running it the power transformer gets to about 130 degrees, when run without the rectifier it is about 110 in the same 30 min time frame. Both the rectifier and the output tube are very close to the transformer, is this too hot or just a symptom from this style of radio it never smells bad, pops, or shows signs of previous overheating and the radio runs well.

5/26/2007 10:25:41 PMkris
Yeah that is in F and all caps have been repalced, thanks, there is no way I wanted to repalace that, these things are getting costly!


:
: Transformer at 130 degrees is ok, as long as that's F. A transformer operated on a hot day will be higher temperature than on a cold day. Transformers are rated for temperature rise. Usually rated for a 40 or 45 degree C rise.
:
: Hopefully you replaced electrolytic filter caps and others if leaky. Bad caps will cause excessive current to be drawn and transformer heating.
:
:Norm
:
::One further question about this radio, when running it the power transformer gets to about 130 degrees, when run without the rectifier it is about 110 in the same 30 min time frame. Both the rectifier and the output tube are very close to the transformer, is this too hot or just a symptom from this style of radio it never smells bad, pops, or shows signs of previous overheating and the radio runs well.



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