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Philco 15 2nd RF Coil - Printable Version

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Philco 15 2nd RF Coil - Dodgen - 09-27-2019

Hello, New here looking for help.  I am restoring a Philco 15.  Upon opening up the chassis I noted wiring changes in which the second RF coil was bypassed at some time in history.  I am looking for data on this coil such as resistance and/or impedance measurements.  It is a three terminal device with a part number as best I can read it, of 4982. Perhaps if it is still good, I can restore the original wiring and re tune.

Thanks for your help!

RE: Philco 15 2nd RF Coil - morzh - 09-27-2019

A simple thing to do: look in the schematic and then ohm out the windings according to it. If there is an open, take it apart (unless it is one of those antenna potted coils), unwind and count the turns plus make the sketch of how the winding was connected to the leads.
There usually a small number of turns so the rewinding is easy.

RE: Philco 15 2nd RF Coil - Dodgen - 09-28-2019

Morzh,

Thanks for your reply. The schematics I have looked at have no resistance measurements. I was hoping for a winding specification in case I have to rewind the coil. This is new area for me. Perhaps records no longer exist.
David

RE: Philco 15 2nd RF Coil - klondike98 - 09-28-2019

Welcome to the Phorum!
Icon_wave

If the coil was bypassed it is likely bad. Here's some info on rewinding RF coils from Chuck Schwark's Philco Repair Bench

RE: Philco 15 2nd RF Coil - Dodgen - 09-28-2019

Bob,

Thank You for the reference.

David

RE: Philco 15 2nd RF Coil - morzh - 09-29-2019

You don't need resistance measurements.
Basically 0.5 to about 100 ohm is the range of a good winding and tens of kiloohms to full open is bad. For RF xfmrs.

RE: Philco 15 2nd RF Coil - Dodgen - 09-30-2019

Mr Morzh,

I finally removed the coil and inspected it carefully. I don't think it is defective. The primary is literally only one turn of wire. ( Hense the very low reading less than a ohm.) The secondary reads in your range. So that leads to another possibility to search: The main tuning caps may be defective. With the removal of the coil, the one gang of the dial tuning capacitor was bypassed and well as a tweeking cap. So I will look there next.

Thanks for your reply,
David

Philco 15 Shadow Meter - Dodgen - 10-03-2019

Yes Ive seen a lot of post for the shadow meter.  My meter is intermittently open and shorted and need either replacement or rewind.  The magnet and movement are good.  I rather not mess this up, so was looking to see if someone does winding.  Thank You

RE: Philco 15 2nd RF Coil - klondike98 - 10-03-2019

I merged your two PHilco 15 threads together to keep it a single topic about your Philco 15. (You can mod your title if you like to something like Philco 15 restoration).

If you don't find someone to do the winding here's a good set of info for you from Chuck Schwark's Repair Bench.

RE: Philco 15 2nd RF Coil - Dodgen - 10-03-2019

Hi Bob, Thank You for the reference. I am have read it over lots. Lol

David