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Dial Cord Slippage ?? 42-PT95
#1

I am hoping this is a simple fix. I have two 42-PT95's that are experiencing similar problems.

When I get near the bottom of the dial (say around 1400 KC) and I turn the tuning knob slowly the dial pointer (and tuning gang) gets stuck and will stay around 1400. If I turn the knob back a little, and then twist it fast it will unstick and move past 1400, sometimes to 1500 sometimes all the way to 1600.

I know that it is not just the pointer that is off, because I have a station at 1450 that I cannot tune if the dial/gang gets stuck. After I twist fast, it will move past 1450 and I will have to go down the dial to tune in the station.

Could this be dial cord slippage ? would some rosin (say from a music store) do the trick ?

Thanks again. This forum has been a very valuable resource !
#2

Sure seems like slippage. Let's see, at 1450 tuning gang would be almost fully open. I would try spraying a little WD-40 in a cup and apply a tiny amount with a toothpick on the bushings or bearings of the tuning capacitor as well as any other ancillary pulley bushings. I would also check to see if the dial cord spring is giving some tension to the cord. Dial cords sometimes stretch, and sometimes there are 2 or 3 holes provided for the spring's anchor to increase tension for just this purpose. Yes, a bit of rosin rubbed into the string might help, but it would probably be temporary. Some just bite the bullet and restring. While doing so, the control shaft area where there the string is wound on would have to be cleaned up really well, maybe even roughed up a little with very fine sand paper to provide a little "tooth" for the string.

I assume the dial indicator is not hanging up the mechanism, but to be thorough, check it too.
#3

Thanks CodeFox, I will attempt to do so.
#4

What diameter dial cord should be used 0.030" or 0.040" or doesn't it matter ?
#5

Doesn't matter much.
Terry




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