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Attached is a link to the Philco 52 schematic. The volume pot appears open. It is a single gang pot item #1 on the schematic. Unfortunately no information on it. Can anyone tell me the value and would that be a linear pot?
Thanks as usual for any help. Jerry
http://www.nostalgiaair.org/PagesByModel...029640.pdf
A friend in need is a pest! Bill Slee ca 1970.
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Because it controls the bias on the IF tube and is fed about 4 mA by the 51K resistor, it should be about 7.5 K Ohms for good control of the IF gain. Linear is OK and wirewound would lessen the shunting of the antenna at high gain.
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Thank you Bill, not certain I understand why wire wound would be better but I will see what I can find. Is your comment about wire wound that it supplies a certain amount of inductance? Not smart on this stuff. Right now not a killer only that in circuit it measures very strange and the radio working (no replacement parts installed yet other than e-caps). No volume until 3/4 of the way up on the pot and it jumps on loud. If it is a wire wound I may be able to take it apart and do some good.
Jerry
A friend in need is a pest! Bill Slee ca 1970.
(This post was last modified: 08-20-2013, 06:21 PM by
jerryhawthorne.)
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Jerry,
Volume control should be Philco p/n 5839, which is a 5K wire wound pot per info on Chuck's site:
http://www.philcorepairbench.com/volctl.htm
Carl
Northern Panhandle, WV
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Thanks Carl, I will check against the P/n on the back. Chuck's site is amazing, I still haven't discovered all the help on it! Doubt I'm going to find one of those but who knows? I'm using his site now on the bakelite caps, the information I have from N/A is so incomplete, need to order Chuck's nice package, I'm going blind and getting a headache trying to figure things out.
Jerry
A friend in need is a pest! Bill Slee ca 1970.
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Quick update on the existing pot, is has a number on the back. It is "6415F" and looks as though it has perhaps been changed in the past ie crappy solder job.
Original or something someone had at the time?
Jerry
A friend in need is a pest! Bill Slee ca 1970.
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Jerry,
For best performance, you need as much wire up for an antenna as practical, and a good ground.
Chuck
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Quote:Thanks Carl, I will check against the P/n on the back. Chuck's site is amazing, I still haven't discovered all the help on it! Doubt I'm going to find one of those but who knows? I'm using his site now on the bakelite caps, the information I have from N/A is so incomplete, need to order Chuck's nice package, I'm going blind and getting a headache trying to figure things out.Icon_lol
Jerry
Chuck's site is wonderful, but beware that some of the info that Philco released on bakelite caps is incorrect. On the obsolete caps, you get referred to a new part number, and the schematic of the cap is shown as a "universal cap", usually with twin caps that are shown connecing pins 1-3 and 1-2. I have run across a couple of bakelites that connect pins 2-3, and the universal cap doesn't display that.. Just pay close attention when you clean out the old cap and check the Philco values against the schematic and you'll be fine.
The artist formerly known as Puhpow! 8)
(This post was last modified: 08-21-2013, 04:01 PM by
Jamie.)