[Heath] DX100 Question

[T. David Cohen]

For some of y'all who remember DX100's.

 

I picked up an old DX100 at a ham fest a couple of years ago and just got
around to trying to get 'er going.  Have had to handle several issues:  The
HV filter caps had to be changed and the upper half of the HV bleeder
resistor was open.  I thought the low voltage filter was OK and then it blew
up (spectacularly) so that had to be changed as well.  As the cap died, it
took out the 5V4 low voltage rectifier.  Not having a 5V4, I replaced it
with a 5T4 and now here's the question, what should the low voltage B+ be?
Since there was no audio, in checking the modulator section, I found an open
driver transformer primary (fortunately I had a suitable replacement).
Also the cathode resistor for the 12BH7 driver looked toasted.  I replaced
it with a 1 watt of proper value and it's getting very hot too.   I'm
getting very nearly 400 volts B+ and there's no reference in the manual to
what the correct value should be.  I can't think of any other cause except
for excessive voltage.  Any help would be appreciated.

l

T. David Cohen



Swamp Road Enterprises, LLC

P. O. Box 900

Prairieville, LA 70769

Cell - 225-202-6376

e-mail -  <mailto:tdavid26 at cox.net> tdavid26 at cox.net

 

 

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