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Philco Jr. Model 81 Volume Circuit
Ron Ramirez
Silent Key
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Posts: 13,776
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Joined: Sep 2005
City: Ferdinand State, Province, Country: Indiana
#6

03-05-2013, 05:32 PM
The schematic came from my website, and I have just corrected it.

http://www.philcoradio.com/tech/images/81.jpg

Yes, the "coil" in question is a capacity winding, and the 4 meg. resistor is indeed a grid leak and is correct as the set was designed.

Bear in mind that the 2nd detector is regenerative.

I found in my own experiments that a 2 meg resistor works much better in this position, and I authored the service tip in question at the link to Chuck's site.
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Ron Ramirez
Ferdinand IN
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RE: Philco Jr. Model 81 Volume Circuit - by Ron Ramirez - 03-05-2013, 05:32 PM



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  1. The PHILCO Phorum
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  3. Philco Home Radios