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loud hum
#8

One can choose what ever method to work with the Bakelite block capacitors.  My opinion is to punch them out and place new inside. That keeps the chassis relatively neat.

I also suggest: Begin with the high voltage filtering electrolytic capacitors first. Again stuffing is tedious and may not "look" well when complete. Leaving the originals in place, disconnect them, install a terminal strip and connect the modern capacitors to that terminal strip...

Then attempt to operate the radio. It may still hum but should still work as it did. The hum can be improper installation of those filter capacitors, check carefully. Then proceed to change out all selected components, two at a time. Then, power test. If the radio fails, then there are just two last component installations that have not been done correctly.

The worst that can happen is to change out everything, then the radio fails. Then, stage by stage testing has to be done, very difficult for a "new" technician...

Caveats, do not alter the positioning of any of the wiring, if a wire is crumbling get replacement wire same size and length, follow same routing. Do not turn, rotate or other disturb mica capacitors, they seldom fail.

There are AC line bypass capacitors likely in a Bakelite block. These should be of the "safety" type, meaning if they fail they will go open and not short circuit.

GL

Chas

Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”


Messages In This Thread
loud hum - by jrc0109 - 12-29-2024, 06:04 PM
RE: loud hum - by RodB - 12-29-2024, 06:58 PM
RE: loud hum - by jrc0109 - 12-29-2024, 07:30 PM
RE: loud hum - by morzh - 12-29-2024, 07:58 PM
RE: loud hum - by GarySP - 12-29-2024, 08:17 PM
RE: loud hum - by morzh - 12-29-2024, 08:24 PM
RE: loud hum - by jrc0109 - 12-29-2024, 11:40 PM
RE: loud hum - by Chas - 12-30-2024, 02:42 PM
RE: loud hum - by RodB - 12-30-2024, 03:19 PM



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