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Philco 20 speaker fiedl coil removal procedure needed
#1

Where can I find one?
This speaker otherwise is totally great - the cone looks like new and it is, I thinkk, original and the spider and all, and even the transformer is good and the whole thing looks great.

But (here flies in a fly and drops in that ointment) as usual, something is screwing up the idyll.
The field coil is open.

Now I want to know how to remove it and whether it requires then any tools to put it back. Does the central magnetic rod stay with the speaker and only the coil is lifted when that nut in the back gets removed?

I have an extra speaker from the 70 that I got supercheap (speaker and chassis from 70 for 15 bucks.....this is what Kutztown auction is for), of which the field coil is in an unknown condition but, should it turn out to be OK, I'd like to introduce it into my speaker. This would make an ideal tester for pushpull 90 and 20 outputs as it then would be fully original.

So....I remember someone somewhere discussing it. I need it in all small minute, if not miniscule, details - this speaker is so great that if I so much as nick it I will commit moral suicide. For a week. And my whisky bill will soar. And my liver will suffer. So...please consider this when you guiding me to the procedure.

No pressure.
#2

Mike,
Read this it will ease your pain!!!
http://philcoradio.com/phorum/showthread...oil+rewind
Terry
#3

Terry

Thanks, but where does it mention anything about field coil removal?
#4

I'd just switch the transformers and be done with it. But on the 20 the nut on the back hold the pole in place. Unbolt it and slide pole out the front and the coil will fall out. On the 70 the pole is pressed in. You will have to drive it out with a socket or something and will have to drive it back in after you switch the coils.
Terry
#5

No, first of as I said I am not sure what shape the 70's speaker is in. It is possible it is shot all through. Second this one is in remarkable shape, it would be a total sacrilege to cannibalize. The cone is like yesterday from the factory.

I'd rather take it off and rewind it if I have no other recourse.

The questio is: with the 2' speaker, when I slide the pole out, do I need to align it somehow when putting it back in or does it get centered by something that is in the speaker?
#6

STOP!!!

Before you remove that large bolt in the back of the pole piece, remove the screws on the cone surround, the screw in the center of the spider, and remove the cone completely (unsolder the voice coil leads once the cone is loose)!

Once the speaker cone is removed, you may proceed to remove the large nut from the pole piece in back.

Don't ask how I learned the right way to do this. Icon_redface

--
Ron Ramirez
Ferdinand IN
#7

Let me guess: the bolt came out taking part of the cone and spiderwith it, ripping it apart?

Thanks Ron, glad I won' do that.
That is not to say I won't do other stupid things. But not in this order! Icon_lol

PS. Wouldn' be doing that today anyway.




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