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Front end variable Capacitor Function?
#1

Hello,

I just bought a model 86 and had posted a request in the cabinet section a few days ago. I got looking at the schematic for this one and there is a strange circuit at the front end which I've never seen before. The schematic shows some kind of variable cap with a line going into the side of the variable cap (?!?).

When I look at the variable cap, I see that when I turn the knob fully CCW the rotor plates hit a tab of metal that acts as a switch I think.

I have not taken apart that section of the radio yet to have a closer look but was wondering if someone might have some info on this setup.

The schematic is a bit confusing on this.

Have started re-capping the chassis, also tested the tubes, found one weak 226 and a very bad 71A output tube. Rest are good. Par for the course...

I should post a picture of my collection of 5 PT-6 Radios that I've collected over the years in case anyone is interested.

The PT-6 was the first old radio I ever bought back in the mid-70's for $5.00 at a garage sale when I was about 15 yrs old. Ever since I've been snagging them when I see them. Great looking radios!

Herb S., Ithaca NY, new member to the Phorum


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Front end variable Capacitor Function? - by hsusmann - 12-08-2013, 10:01 PM



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