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Tapped tone compensated volume control
#1

I am a newbie here, so I appoligize in advance if this has been covered. I am faced with several restorations of Philcos and other brands that have a tapped volume control. Now the question, if a volume control is definately destroyed, how do I (we) deal with the tone compensating tap? Thanks in advance.
Don Ferguson Icon_eek
#2

One source for NOS replacements is Mark Oppat... moppat@comcast.net They tend to be spendy.

I've heard of folks fabricating a new tap but that's a difficult task. The other option is to just leave off the tap. Fortunately, in many years of messing with radios I've always been able to scrounge a replacement.

Good luck,
Bill
#3

Hi Don, and welcome!

Quick answer: As Bill suggested, contact Mark Oppat. Here's his website:
http://www.oldradioparts.net/

He is able to furnish many different types of volume controls, including tapped versions.

Next choice: Find a junker Philco and take its volume control. Many of the larger Philco sets up to and after WWII used tapped volume controls which can be adapted to older models.

Third choice: You can use an untapped volume control, and the radio will work, but the tone quality will never be the same especially at low volume levels.

--
Ron Ramirez
Ferdinand IN
#4

Guys, thanks very much. It is about what I expected. This is what I have heard in my local club. I will keep Mark Oppat in mind also.
Don
#5

Well you could approximate the tap (which I assume the link that is broken,) with fixed resistors midrange, and you might be OK. You did do Deoxit? Taps on pots were always a little tricky, some reacted with sweating of the contact, more violent means are possible. Were they

trying to create a "loudness" or damping control for AM radio way back then?
#6

Unless the resistive element is burned up or worn right through the vast majority of volume controls can be repaired, even ones with broken shafts sometimes. Nine times out of ten they just need to be taken apart and cleaned if they don't work right as they are. Just spraying them out usually isn't good enough.
Regards
Arran




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