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philco 625 voltage way to high
8/7/2007 9:59:14 PMblackbird
I have 300 volts at the plates that should be at 258.
I am kinda stuck on what I should replace. any ideas?
it has been recapped completely.
8/7/2007 10:05:10 PMNorm Leal
Hi

Does the radio operate? If not your 42 tube is probably not drawing current. Try another 42 tube. This tube draws most of the current in a Philco 625 radio which should load down B+ voltage.

Recapping a radio and high line voltage can also cause voltages to be high.

http://www.nostalgiaair.org/PagesByModel/810/M0013810.pdf

Norm

:I have 300 volts at the plates that should be at 258.
:I am kinda stuck on what I should replace. any ideas?
:it has been recapped completely.

8/9/2007 6:50:19 PMblackbird
Yeah it works it just seems to get kinda hot.

:Hi
:
: Does the radio operate? If not your 42 tube is probably not drawing current. Try another 42 tube. This tube draws most of the current in a Philco 625 radio which should load down B+ voltage.
:
: Recapping a radio and high line voltage can also cause voltages to be high.
:
:http://www.nostalgiaair.org/PagesByModel/810/M0013810.pdf
:
:Norm
:
::I have 300 volts at the plates that should be at 258.
::I am kinda stuck on what I should replace. any ideas?
::it has been recapped completely.

8/11/2007 10:17:58 PMThomas Dermody
What gets hot? Do the tubes get excessively hot? This, of course, would be because of the excessive voltage. Does the power transformer get hot? If you cannot find any other trouble, could be a shorted field coil or maybe a shorted winding in the transformer. How are your filament voltages? Could also be a shorted bias resistor/choke in the B- circuit, though this might cause distortion in the audio, and would cause the output tube to draw excessive current. I don't see this as a possible problem.

Also, did someone possibly replace the power transformer? What is its B voltage?

T.



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