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deciphering Philco Potentiometer numbers
#1

All, I'm working on a Philco that has a flex shaft potentiometer.  Written in blue ink on the side of the pot is "4248 PHILCO 885072".  I measure this pot at 1.25M but according to the schematic it should be a 350K.  Can anyone decipher these numbers?  I've got another thread on this radio here http://philcoradio.com/phorum/showthread.php?tid=14172 and I posted on the antiqueradios forum as well http://antiqueradios.com/forums/viewtopi...6&t=297064.   I think I'm going to need a custom built pot and I need to make sure I've got the value correct.
Thanks,
Keith         [url=http://philcoradio.com/phorum/showthread.php?tid=14172][/url]
#2

Keith

Have you tried Oldradioparts?

On a smaller Philco I successfully used a today's pot.

Also sometimes if the pot is still a pot, only with much higher value, some effect could be achieved by simply paralleling a resistor across the end pins, so the total resistance is in this case 350K (500K resistor).
In some cases even without doing anything it will work.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#3

Thanks Morzh,  I've contacted oldradioparts and I'm pretty sure he can make me a new pot.  I went ahead and opened it up to see why the switch wasn't working.  There is a metal tab that has been folded back and forth  to the point where it is literally held on by a thin tread of metal.  If I could find a pot with this same type of switch I could probably fix the switch and then fix the pot by putting a resistor across the terminals as you suggested.  Is this a common switch type?
Thanks,
Keith


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#4

I think you can just clean contacts of the switch with alcohol and then some Deoxit. If they are not bent it might work.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#5

The tab that engages the switch is cracked to the point that I could break it off with a feather. I definitely need a new switch or a new switch/pot.
Keith
#6

  Talk apart and braze it….if copper,,or try solder,,,maybe




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