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Philco model 81
#1

Several months ago I posted in the want ad section that I was Interested in finding a model 80. Nothing came of it and I kept on looking until I found something better a model 81. Electrically it's the same as the 80 but it has two bands. It covers the AM broadcast and the old police band from 1.6-2.7mc or so the "police" band isn't calibrated. The cabinet is beautiful except it has the wrong grill cloth.

The chassis is pretty good with some rust up by the tuning condenser. It was sold to me as working so I gave it a try and it did kinda. I say kinda because I had the hook the ant to the grid cap of the mixer tube. This meant that the ant coil was open. You can't turn the set off. The off/on switch was broken and I noticed something odd, the band switch mechanically acted like a volume control. Hummmm I thought that's interesting. So out came the chassis. First things first pulled out the volume control/off-switch. Someone replaced the original with one that was not quite the right value but turns out that it works very well. The switch just needed a good cleaning and it was back in tip top shape. Checked the resistance of the ant coil primary and surprise it was open. Pop it out and rewound it with 25T of 36 magnet wire. Now I could turn the set off and on and the volume control worked great!

Now for the interesting problem. It was missing the band switch and in it's place was a .5meg pot with a switch. I've read about these but in 40 years of servicing and collecting I've never seen one. During WWII if you where not an American citizen and where from Italy,Germany,or Japan and you had a shortwave radio your radio would be neutered. Meaning that the shortwave section would be disabled so the set would only receive the AM broadcast signals. This was done so that friends of the Axis couldn't send messages to spies here in the states.

Sometimes this neutering unrepairable as the band switch is totally destroyed and the coils removed That's makes it pretty difficult to fix. In my case I just need to replace the missing switch which is simple. I can wonder out to the garage and find something that will do the trick.

I guess the $64 question should I? It would be fun to listen to my ham buddies down on 160mtrs and I can crank up the sensitivity (regeneration) and copy cw and ssb.

Terry N3GTE

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#2

Hello, Terry: I have never heard of that, but it would explain why one of the model 44 chassis that I have had some major internal surgery done that made it a broadcast band only reciever. Hmmmm.....

I will respond to your question with a question: Why not leave it as is and listen to ham/CW broadcasts on another radio that recieves the lower MHz band?
#3

Here's some additional information. http://www.antiqueradios.com/forums/view...5682d791de

Terry

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry




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