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Replace IF transformer caps?
#1

Hi all, I'm restoring a Philco 40-155T slant front and it's coming along great. Got her all re-capped and a re-coned speaker is on the way. This radio sounds really nice, really powerful and I have a good cabinet. 
I'm questioning if, since I'm into it now, I should replace the caps in the transformer cans. The radio plays awesome, and it's some trouble to pull the cans, and I always hate doing surgery around coils. But maybe I should just do it rather than wonder later. What d'ya think?
Thanks,
Alan
#2

No, the caps inside caps are usually micas and should be left alone unless explicitly failed.
Goes for all mica caps.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#3

Unless they are post war K-tran or Automatic style IF cans, the mini If cans used in millions of AC/DC sets from the late 1940s onward, leave them alone, Philco used either molder micas or ceramic caps in these sets I think, except for a large one used on the pushbutton banks.
The one on the P.B bank does go bad so I would change it, it looks like a sandwich with no case on it. One item to check though is the audio output transformer, the primaries on those often fail in these sets.
Regards
Arran
#4

Thanks guys, just the answers I needed, didn't want to go there. Thought maybe I would be heading off the dreaded silver mica disease.
Alan
#5

Silver mica disease ails a specific type of caps, the open kind, not the overmolded laded type. At least not as badly.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.




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