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When received, my 38-690 had a replacement dual pot volume control. The issue I have is that the volume cranks up loud really fast with the control just cracked. I suspect the pot was replaced with a linear taper instead of audio taper.
Can you confirm how sensitive the volume control should be when starting from all the way down?
If what I suspect is really the case, I’ll look for a replacement through an add or Mark Opatt.
Thank you.
Tony
“People may not remember how fast you did a job, but they will remember how well you did it”
(This post was last modified: 12-28-2019, 07:02 AM by
tbone.)
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What you can do is set the control @ the center of it's rotation and measure the resistance from the wiper to each end. If it's about the same it's a linear taper.
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!
Terry
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I measured both pots and they are roughly equal to wiper on each side when centered. I guess that answered my question. Before I start looking for one, would both pots be audio taper? My gut says yes.
Tony
“People may not remember how fast you did a job, but they will remember how well you did it”
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According to the
service info the original part is 33-5240.
There's a previous discussion of that part here:
https://philcoradio.com/phorum/showthread.php?tid=13625
Quote:Part #75 is 500K and part #76 is 100K, for the dual pot.
No mention of the taper type but I'd bet on audio taper too (it is a volume control after all).
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Thank you guys for your help. I’ll start searching. The radio works, just has a volume control that’s too sensitive.
Tony
“People may not remember how fast you did a job, but they will remember how well you did it”
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Mark Oppat is making one up for me.
Tony
“People may not remember how fast you did a job, but they will remember how well you did it”
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