[Elecraft] Has anyone epoxied their toroids after they werewound?

[peter gerba]

Hi;

See the article below. Roy does some testing with various materials.

I don't seal anything unless it's going to be exposed to the weather.

Pete kn6bi



"Toroidal Inductor Measurements" by Roy Lewallen, W7EL December, 1998


http://www.qrp.pops.net/w7el.htm

 -----Original Message-----
From: 	elecraft-bounces at mailman.qth.net
[mailto:elecraft-bounces at mailman.qth.net]  On Behalf Of John, KI6WX
Sent:	Friday, May 18, 2007 2:34 PM
To:	J F; brian-wb6rqn at lloyd.com; Elecraft Discussion List
Subject:	Re: [Elecraft] Has anyone epoxied their toroids after they
werewound?

Applying any material (Q-dope, epoxy, hot glue) to the wound toroid is not a
good idea.  It increases the interwinding capacitance and can effect the
performance of the various toroidal transformers.  This is especially true
in the transmitter section where the toroids are tuned with a fixed
capacitor to increase the power transfer.  The value of these capacitors was
determined without any coating material on the toroid, and changing the
dielectric around the toroid windings may require a change in the
capacitor's value.
-John
 KI6WX



> Never have epoxied toroids, I can see one major
> disadvantage using this method... You'd never be able
> to rewind the same core. Epoxy is a real bear to
> remove.
>
> I've used hot glue to keep toroids in place, a little
> easier to remove if needed.
>
> Think you're better off with nail polish or acrylic..
>

_______________________________________________
Elecraft mailing list
Post to: Elecraft at mailman.qth.net
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
 http://mailman.qth.net/mailman/listinfo/elecraft

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

__________ NOD32 2277 (20070518) Information __________

This message was checked by NOD32 antivirus system.
http://www.eset.com