[brandonkr1]

Hello I’m new here! I have a philco 60 cathedral radio that’s been in my family for many years. It has an open oscillator coil, and I know it needs rewinding ? what I’m curious about is whether a coil from a philco 87 would work? If it will, then I can swap it out real quick. If not, then I’ll get ready to re wind ?

[brandonkr1]

Hello everyone! I’m new here. I have a philco 60 that’s been in my family for years. I remember listening to it when I was little. My dad is giving it to me, but it doesn’t work. I plan on replacing all caps and testing all resistors. Basically an electronic “restoration” if you want to call it that. The reason it doesn’t work is because the dreaded oscillator coil is open….    It worked perfectly before that, so that’s the first thing I’ll do, then I’ll work on the caps. My question is, how critical is it to wind the coil perfectly? It’s the lower section of the oscillator that gets all corroded. I know it’s about 18 turns, and I have 36 gauge wire for it. But I’m worried about overlapping and gaps as I wind it…. I will try my best to get it nice, but I know it’s not going to look like a factory job… for now I’m not concerned about the antenna coil because we never use the short wave. But if I’m successful, I may rewind the antenna coil at a later date since it’s only about 7 turns I believe.

[Ron Ramirez]

Hi,

I merged your two threads together. The Phorum Rules prohibit having more than one thread on the same subject by the same author.

Fortunately, for those older Philcos, it isn't super critical to get the rewinding perfect. It is, however, critically important that the new winding be wound in the same direction as the original winding, else your oscillator will never work.

And keep in mind that antenna coil is used for the standard AM band as well as "short wave" (actually what was then known as the "police" band, 1.5 to 4 mc), so if it has an open winding, it too will require rewinding.

[brandonkr1]

Okay looks like I’ll rewind them both if needed. Thank you so much!

[Radioroslyn]

To answer your other question abt the model 87 coil as a replacement. No the 87 use a different design (trf) and has no oscillator stage.

[brandonkr1]

Okay I was curious about the 87 coil because there are 3 available on eBay! If anyone needs those, check eBay! It’s a lot of 3. 

I have been watching YouTube videos on winding these coils, and it looks straight and forward, so I should be okay with it. Just have to make sure I don’t drink too much coffee beforehand! 

[Brad Winder]

Brandon,

I find drinking wine during repairs like this helps. Coffee is a no-no.  

[brandonkr1]

Brad 

? if I’m lucky, the coil will have a break near the soldering joint, so if that’s the case, I could just resolder it. ? I’ll have a look at it today and see. I wonder if anyone has some NOS coils stashed away somewhere. 

I posted a picture of the front and back of the radio at the beginning of the post, but it looks like they didn’t show up

[Ron Ramirez]

How to Add Images to Your Posts:

https://philcoradio.com/phorum/showthread.php?tid=4407
https://philcoradio.com/phorum/showthread.php?tid=29

[brandonkr1]

Okay folks so I got the oscillator coil out of the 60. The ohm reading I got was something around 125!!! I believe the schematic says it should be about 3.0…. I’ll attach a picture as you can see, no leads appear broken, but why on earth am I getting 125 ohms? I checked the upper part of the coil and got exactly 2.4, which is what the schematic calls for. So I’m confused…. I know if that lead was broken, I wouldn’t get any reading at all 

[Radioroslyn]

It's called rot. If you unwind the small coil at the bottom you'll find some green dots where the copper wire is failing.

[brandonkr1]

Oh I see, I didn’t know that would throw off the reading. I just figured I would get the correct reading or none at all. 

So once I rewind the wire, it should read at around 3.0 ohms correct?

[Radioroslyn]

As a rough number 40 gauge wire is 1 ohm per foot. 38g is going to be a little less .67 of an ohm per foot. So you can calculate about how long of a piece wire you'll need to rewind your coil. That's the long answer short answer is yes.

[brandonkr1]

Okay thank you so much for all the help! You all are amazing!

[brandonkr1]

Got the old coil unwound! The wire itself wasn’t broken, but the insulation was all gone. Which explains my wacky ohm reading. Once I had the wire removed, I laid it out flat so it’s not overlapping itself, and then I got 2.4 ohms! So now I know that the oscillator coil wire itself doesn’t necessarily have to be open in order to cause problems!