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Hello Everyone:

I am restoring my Philco Model 37-116 Manual Tuning set. This will be a great set when finished and certainly is worth fixing. When I received the set the Shadow Meter was working. The radio had been partially restored. Not all the caps were replaced. It had a bad broadcast band antenna coil and a open Band 2 oscillator coil. It also had two wiring mistakes. I replaced all of the rest of the caps. I replaced some of the resistors. I replaced the two coils and corrected the two wiring errors so that the radio wiring agrees with the schematic. I have an outside long wire dipole antenna which I have connected to the radio. The radio works well receiving stations on all bands. The shadow meter, however, is inoperative. When you turn on the radio the shadow meter is at first close together but as the set warms it opens up. It does not respond when you tune into a station. I checked the shadow meter coil. It has a resistance of about 1.5 K ohms. The other thing I tried is this. With the receiver in operation and tuned in to a station, I can remove either the Discriminator tube (6H6G) or the A.V.C. tube (6J5G) or the Magnetic Tuning Amplifier tube (6K7G) all with no effect to the station that is being received. Today, I carefully re-checked all wiring in the vicinity of these 3 tubes. The wiring agrees with the schematic. I also placed my digital voltmeter across the shadow meter coil with the radio in operation. There was no change to the about 12.5 volts d.c. I read as you tuned into a station. I would like help in troubleshooting this problem. I will be happy to follow directions to find the problem. My thanks for anyone who wants to help.

William
Hi William,
Have you read the tips on Chuck's site:
http://philcorepairbench.com/tips/svctip01.htm
Carl:

Yes, I have. The coil does not appear to be open.

William
Hello:

Here is the link for the schematic. Maybe this will help?

http://www.nostalgiaair.org/PagesByModel...013199.pdf

William
Hello Again:

I found out today that Philco issued a factory change for the magnetic tuning transformer. The part number was changed from 32-2217 to 32-2361. I checked my magnetic tuning transformer (Schematic Number 81) but could find no part number on it. Maybe this is why there is no AVC action and my Shadow Meter isn't working?

William
Hello William. Perhaps that part# change-over would be mentioned in a old Philco service-bulletin issued back in the day? I dont have much Philco data at all, except the bakelite-condensers & more book. I will look thru what I have in Philco "service-bulletins" I found awhile back in a old shop when I bought remaining inventory from a long closed shop.I have some of that old Philco authorized dealer service data in a box I havent gone thru yet. If I can find any info on that part # update, I will post my findings here. Otherwise, hopefully someone else here has most of the orig Philco service-bulletins that can help you find the part # and specs!? I usually fly by the "seat of my pants" using my JF Riders books on most restorations, and have found many mistakes on the schemats as published, especially Philco part #'s!! Sometimes I have had to purchase copies of service-bulletins published by the mfgrs to get correct data from collectors that have them. Atwater Kent also did a good job confusing service people by using part # only parts and also burying orig filter caps & chokes, and power supplies under tar all in a 3 pc metal power pack housing!! I have restored a couple of those using a heat gun to melt tar to carefully replace the defective parts. That way, dealers service depts could only decipher the part#'s of the days to make the money on their particular "brand" of radios they retailed on their service benches. Bet you knew about all that anyways!! Hope you get your shadowtuner working soon!! I am about to start a restoration on a shadowtuner model Philco myself in a 37-630 chassis that has been dead for many yrs!! That will be fun!!?? Thanks to Ron for helping identify my chassis! Randal