The PHILCO Phorum

My mute switch is shorted whether it's pushed in or let out, need some insight on fixing this. We have looked at and read all the patent information and viewed the drawings, I need someone's personal experience with this problem to help better understand what needs to be done to correct this.

I had the same problem with mine. IIRC taking it apart and cleaning everything up fixed it.

Ronin

1. When checking the switch make sure your volume reg is at max position or you will see the short where there is none.
2. You have to take off the handle assembly, the hub ring holding the dial and get to the point where you can see the contact ring that goes around the outer part of the shaft. The shaft should be wrapped in some insulating material. The ring should not be connected to the shaft at this point. The horizontal part (the contact that goes into the push-handle assembly) should be free at this point. If the copnnection exist your insulating wrap is bad probably.
3. If it is good then see if the short occurs when you put the handle assembloy back. This requires some finess but I eventually figured how to do that easily and so will you - it becomes obvious when you assemble the handle back.


All in all, there is nothing there except one spring contact and the insulation. You ahve to trace where it breaks.

Well had to take it apart to get to the mute assembly and it was buried in grease and one of the insulating washers was missing. So now after putting it all back together the mute switch is working and the tuning asembly works like butter.all back together.

More pictures of the assembly and disassembly.if you have done a 37 or 38-116 you will recognize how deep in the assembly we had to go to clean and re- assemble this.

Ronin

Yeah, do you see that wrap (brown) where the ring goes around?
See if the insulation is reliable and there are no rub-throughs.
This ring and the vertical contact where the wire solders to should be insulated from the chassis reliably.
It should only make contact when you press on the handle.

Well, the worst case you will not connect the wire and will hear some noise while auto-dialing. Not desirable but acceptable.
Notwithstanding the fact that nowadays when the stations are no longer that abundant the auto-dialing is more of a "hey look! it works!" thing rather than a really useful thing.

We tested it and it works , the cleaning and the additional fiber spacer made all the difference.

Almost done. New grill cloth in the center and original grill cloth over the clarifiers.

Almost done. New grill cloth in the center and original grill cloth over the clarifiers.

Nice job and that mute switch is a real pia if the little insulating tube is gone. I wrapped the shaft with some telfon tape, not a elegant solution but it worked. The whole dial assembly on that radio is really complicated. Glad you got it working.
Jerry