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Philco 17 tone control
#1

I picked up a model 17 last weekend and have been working on it off and on since then. It's the one that has the chairside radio and a separate speaker connected with a cable. It's going to be a great radio. Very powerful audio. I rebuilt the tone control yesterday and despite trying two combinations of components (one per the schematic, and one according to the changes) I can not get much variation in tone from the different positions. Only the final position of the control makes much difference. This radio has been worked on a lot and I really couldn't tell what was supposed to be there originally. Any ideas?

thanks,
Steve Chambers
#2

Steve

Great find!

It's been a while since I worked on a Model 17; the tone control on the last one I restored worked O.K.

As I recall, it had the later tone control circuit as shown below.

[Image: http://i326.photobucket.com/albums/k420/...17tone.jpg]

Don't know if this will help?

--
Ron Ramirez
Ferdinand IN
#3

Thanks Ron!

Yes, this helps. It's nice to know I followed the wording of the changes correctly.

I'm not sure if it qualifies as a find, as I purchased it on our favorite auction site.

It was a short drive to Western PA to pick it and I was the only bidder. The price seemed reasonable for such a nice radio. The finish on the chairside part is OK as is.

Anyway, the chassis has been worked on a lot. The Nostalgia Air schematic is not the same as the one you posted, but changes are listed which do match your schematic. The radio seems to have parts from both versions. Some parts were missing altogether. I have ordered a clearer schematic. I wired the radio according to the original and then according to the changes. I like the changed version better, but the tone control effect is still very subtle. On a good quality signal you can hear the tone change, but it's much more gradual than any other Philco I've worked on. It's almost as if the engineers wanted a continuous effect. Sure uses a lot of parts for such a small amount of control. Still, a very nice radio and the connecting cable (must be 20 feet long) is in good shape too.

Steve Chambers




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