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Philco 71B 3 position tone control
#1

Hi, everyone:

I have a late model 71B with a shadow meter. Before you tell me the 71B didn't have a shadow meter, dig deeper, because the later ones did, in fact, come with a shadow meter, and in fact I've seen two of them, and regret not buying the second one! (Both were cathedrals, though I believe the console versions got the shadow meter earlier than the Baby Grands did.

Anyway, this radio has a 3 position tone control, which I want to recap, but I don't know what the values of the capacitors are. The schematic I have shows only a single position tone control, which I assume was on the earlier units similar to the 70.

I'd like to find an updated schematic, or hopefully someone knows what I'm talking about and can tell me the values for each position. If 0 is off (left), and we count 1, 2, 3 for each step, there are actually 2 wires going to the contact for Position 2, and one each to 1 and 3. Presumably the capacitors are all tied together for the other side to the common wire.

This is a rusty crusty set that should have been junked, but I'm going to try to fix it. When I got it, it was able to tune a handful of stations, but not KFI, who's antenna I can see from my house, so I knew something was wrong, and when I pulled the chassis out, it looked hopeless.

I rewound the shadow meter and got it working, and sprayed plenty of Rustoleum on the rusted chassis, and now I'm going to undo some "shade tree" restoration work done underneath and see how good I can make this junker! (I actually found a replacement tuner cap assembly for it, too, so hopefully it can get KFI. I mean, any coil of wire should get KFI at my house!)


Thanks.

Dan

"Why, the tubes alone are worth more than that!" (Heard at every swap meet. Gets me every time!)

Philcos: 90, 70, 71B, 610, 37-61 40-81, 46-420 Code 121 to name a few.
Plus enough Zeniths, Atwater Kents and others to trip over!


Messages In This Thread
Philco 71B 3 position tone control - by ntsc525 - 04-18-2019, 10:39 PM



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