Hi,
A friend of mine is rebuilding a Philco 630 (1936). there is a paper capacitor, rather large, labeled 30-4134S. It is labeled Philco.
Can anyone tell us the value of the capacitor. It doesn't seem to show in the schematic but looks like it's been there for a long long time. It's on the input (B+) side of the shadow meter.
Thanks,
Mark in Prescott
OK, we found that the Philco 30-4134 is a .25uf, 400V paper capacitor. Does the suffix "S" have any significance?
Also, can anyone venture a guess why a 0.25uf cap is in the shadow meter circuit? It looks untouched from when the radio was new as nothing had been done to this set. That cap just doesn't show up in a 630 schematic.
Thanks (for Doug)
Mark in Prescott
I have no idea. Sorry. But you should post some pictures of the restoration, as this sounds like an interesting radio.
If the extra capacitor ,(in question),.. you found in your set isnt on the schematic, delete it. Unless you get hum from the B+ thru the shadowmeter coil after full electronic restoration, the .25uf bypass cap most probably isnt necessary at all. Recheck the schematic closely tho. Sometimes, the orig assembly-line techs would use whatever caps they had handy, and if it was quitting-time ( 5:00) pm at the old Philco factory in 1936, anything "spare" could have been used, in weird places indeed!? Ive run across many such scenarios in many mfgrs sets that didnt "sum" with the schematics before also! Hope this info helps.
Best of luck in restoring your vintage Philco!
