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All, I'm working on my first radio project, a Philco 47-1227 and thought I'd start by recapping the unit. Most caps are clearly marked with their capacitance but there is one that has me stumped. It is one of five electrolytics. There is a 25uf +10uf in can, a 10uf + 10uf also in a can, and a fifth mystery electrolytic. The info printed on the cap reads;
Philco
232 623
12D46 62
5 50
I've ordered a schematic but before it arrives can anyone decifier the capacitor code? It reads 12uf on my digital as well as vintage cap testers. I've run this by another forum and the leading guess is that it is a 5uf 50V cap. I'll know for sure when the schematic arrives but was wondering if the label makes since to any of the philco experts out there.
Thanks,
Keith
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There is a 5 uF electrolytic in the FM detector circuit - C325. I assume this is what you are referring to? The other electrolytics are in cans, as you stated, and are part of the power supply filtering network.
This 5 uF electrolytic is Part No. 30-2417. According to Philco's 1950 parts catalog, it is indeed 5 uF, 50 WVDC.
The numbers you listed do not correspond to anything in the original Philco 47-1227 service bulletin.
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Ron Ramirez
Ferdinand IN
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Thank you Ron,
I figured there would be some Philco experts out there that could help me out. This is my first radio so you can be sure I'll have additional posts in the future. I'll replace the 60 or so caps. Is it good practise to replace the resistors as well?
Thanks,
Keith
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Resistors seem to run the gamut from mostly ok to mostly bad. As you're going along changing caps take the opportunity to measure them as you go since often you need to lift one end to get a good reading. You'll probably find a few that have gone high in value but normally they don't merit wholesale replacement like the paper caps do.
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exray Wrote:. . . You'll probably find a few that have gone high in value but normally they don't merit wholesale replacement like the paper caps do.
Unless the resistor's "higher drifted" value is more than 20% of the nominal resistance. Then it shold be replaced as a standard rule of thumb.
Chuck