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Advice on winding new coils for old receiver please

Started by xtal_01, September 25, 2022, 11:22:12 PM

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Well, I was so excited last year to finally find a Monarch receiver to complete my candle stick phone  ... took a few years but finally found one.

Today I put a meter on it ... oh no!

Ohms jumped all over.

Every time I laid it down ... got 112 ohms  ... stood it up ... 10K  ... tapped it .... 500 ohms ....

I looked at the ends ... seemed like they are soldered well

Tried contact cleaner ... no change

Both coils are grounded between them but I don't understand how as I can see the connection between them and it is not touching anything.

Anyway  ... it will be tough but I think I can get the coils out (need to grind off the top as it is crimped over).

I will need to rewind the coils by hand .... I have not done this in years and year and years (think I did it to a friends boat magneto years ago because the part was obsolete).

So, any suggestions on how to winding these coils>

I am not sure what size wire it is  ... yet ... I can measure it when I get it out

I can unwind it and measure how much wire I need to put back on it.

Where is the best place to buy wire?

Any advice would be greatly appreciated.



Probably only one of the coils are broken, with a little work you are able to remove the insulation where they are connected together. It will probably work with only one coil, but not perfect.

It is not easy to remove the coils an unwind them, but of-course you may try. As long as it is defect you haven't much to loose.
You will have pretty high tolerance of number of windings and resistance in coil.  Wind on what you have of suitable wire that looks close to what it has already, when it is full... it's full. The polarity of the coils are important, if you have wrong direction one will work against the other.



Until you have solved the problem put in a receiver that you may get in to the housing, add some weight and use it. Any receiver with DC resistance between 40 and 220 ohms will probably work. :) As long as the membrane is mowing freely.


Quote from: xtal_01 on September 25, 2022, 11:22:12 PMBoth coils are grounded between them but I don't understand how as I can see the connection between them and it is not touching anything.

Have you measured the resistance of both ends against the ground? Most likely only one coil will be defective, and probably cause the ground fault, too?
You will need some sort of apparatus to turn the core for rewinding. When I did that, I built myself a coil winder from Lego bricks... it worked, but the result is mixed. I could not manage to place enough windings on the cores I improvised. If you could salvage the existing core you would be better off I think. But it may be tricky to get the core off the iron.


Personally, I would leave it alone.
In the future you may find a broken one with a good element in it.


Thanks guys!

Well it is not good to me this way ... and it took me 5 years to find one of these .... maybe someone out there knows where I can find a Monarch receiver?  I would gladly buy another if I can find one.

I think I will take a shot at fixing this one.

It might just be the connection where the two coils come together.

I do need to break the swage to get the metal retainers that hold the coils off.

I am not sure the easiest way to do this ... I started scrapping at it tonight ... might be able to get enough metal off to let them pop off.

If I was going to do a lot of them, I would make some kind of coil winder.  I think for one or two, I will just take a few nights and slowly go round and round.

I will be sure to count the windings coming off  ... and try to match the gauge as best I can.

Crossing my fingers.



Since the receiver is not good the way it is, I decided to take a shot at repairing it.

After looking at it, I decided the problem must be the connection between the coil and the frame.  My guess was since I can't see a joint between the two coils, they joined the non terminal end to the core.

Got the coils out (minimal damage) ... right away I could see oxidation and rust.

I unwound the coil ... tried to keep count of the windings.

Wire is .005" ... #36

I will measure the length ... I think it was about 550 windings (lost count a few times).

I was right ... the coils joint together using the core and frame as the jumper.

At the end, the wire was just press against the core .... then a few layers of paper ... then the windings.

So, I tried a bit of steel wool on the core ... better but not great.

How should I clean the metal parts?

I can buff them (use my dremel) ... or use electrolysis  ... or vinegar ... or navel jelly ... or ????

Once clean, I can try rewinding using the existing wire ... if this does not work, I will measure the length of wire and try winding with new wire.


Possibly rust and an oxidized soldering joint caused the fault. IMHO the ground connection was not intentional, but part of the problem.
For rust removal I had good luck with citric acid. It is available in supermarkets here and also recommended for the maintenance of coffee machines. It is cheap, safe and good to work with. It works even quicker on non-ferrous metals. Those flat parts would be easy to just sand them off, or do I overlook something here?
The old wire might work just fine if rewound, but as well might not. If the old enamel isolation  fails,and some windings short out, you won't notice it measuring the DC resistance. But the performance of the receiver would greatly suffer. Good luck with your repair, it appears to me you are on the right path!


Just realized I never followed up on this ...

It worked!

Built a simple had winder ... the counter was the most important part as I lost track twice trying to count.

Ohms matched almost exactly to the original!

I "cheated" a bit ... soldered the ends of the coils together (hidden behind the bracket).

Thanks !!!!!!!