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Hello,
I have a bad field coil on my Philco 84 and will try rewinding it. I was able to get the field coil assembly apart and access the coil itself but am not sure of the wire gauge size. I think it might be 35 gauge but would like to know if anyone knows for sure?
Regards,
Ctkid
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City: Roslyn Pa
From what I can tell the coil is rated for 40ma. 35G is good for 42ma as per The Radio Amateur's Handbook 1956 edition
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got it!
Terry
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The wire size can be measured with a mechanical micrometer or caliper. Allow a couple of thousands for the film insulation.
Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”
Posts: 18
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Thanks for your responses!
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I don't know, 40 ma seems kind of low for a set with a #42 output tube, the #80 rectifier tube is rated for 125 ma I think. I would try measuring the actual wire used in the field coil. Of course I am assuming the the field coil in the model 84 is used as a filter choke in the positive side of the B+ circuit, and not in the negative side on the bias supply, which would require a lower current rating.
Regards
Arran
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Philco spec the coil at 40ma for that K speaker.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got it!
Terry
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
The speaker used in Model 84 is type
SB (not a K) and it has an 1140 ohm field coil rated at
50 mA.
(source: the Philco Speakers spreadsheet, downloadable at
this link on this site.)
--
Ron Ramirez
Ferdinand IN
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