I bought a lovely old Panasonic R220-J from marketplace for not much. After a bit of poking around I discovered a faulty band selection switch. There were a few options online so I ordered a replacement. In the meantime I could not resist playing around with the switch and after a bit of jiggling I got the switch to make reasonable contact. The radio worked well as long as I did not touch the switch. When I saw what was involved in changing out that switch I got anxious. Never mind I mean the worst outcome would be a ruined radio that owes me next to nothing. Then I came across a post somewhere that recommended spraying the switch with contact cleaner. Off to Jaycar and I arrived home with a can of Non CFC Ozone safe propellant. For use on delicate electronic circuits eg switches etc. A quick spray and some time to let it dry. Turned the radio on and the switch was good ( It was still a bit scratchy but way better than before). I decided to still replace the switch when it arrives but for now the radio was playing away happily on the bench. Fast forward a couple of days and I went to change stations on my new favourite radio. The dial pointer was stuck. Hmmm. No amount of turning back and forth would budge it. I disassembled the cord and rotated the cap back and forth. It was stiff at first but quickly loosened up. Only to bind again after a few seconds. I began to think that I had ruined the capacitor with that contact cleaner. Given the proximity to the switch I was pretty sure this was the case. Some cleaner must have got into the cap so I removed it and tested it. Buggered. Absolutely gawn. One side tested as a capacitor with 35pf of capacitance but did not change at all when I rotated the dial. The other side tested as faulty or unknown device and rotation made no difference.How could I be so stupid?
So this brings me to the point of this post. The only similar poly caps I can find are for am\fm band receivers. My radio is am\sw band. Not being able to test the old unit I don't know if these caps will be in the ballpark for my radio. The one I have ordered is this.
Switch CBM-443BF-1AB4/088AM+FM Radio Thin Film Variable Capacitor 270P Double +20Pfm Double. Does anyone know if this might work? The dimensions seem right. Or are there any suggestions on where to get a replacement?