Toroid core losses

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Original poster: "J. B. Weazle McCreath by way of Terry Fritz <twftesla-at-qwest-dot-net>" <weazle-at-hurontel.on.ca>


Hello Coilers,

I'm using a small RF choke as per instructions I got from Dr. Resonance
to protect my PDT from stray RF finding it way into the windings, along
with a horn gap type safety gap right at the PDT.

The choke consists of a toroid core I salvaged from a computer power
supply with three turns of my high voltage lead from the PDT to the
coil wound through it.

I noticed after about a minute run that the core was noticely warmer
than it had been prior to firing.  Not hot by any means, but still a
good deal above room temperature, telling me there is a bit of power
being disappated.

What frequency do these computer power supplies do their switching at?
Maybe the core material is not suitable at Tesla coil frequencies?
My coil operates at 250 kHz, by the way. 

73, Weazle, VE3EAR/VE3WZL
G-1#1214

Listening: 147.030+ and 442.075+
E-mail:    weazle-at-hurontel.on.ca
           or ve3ear-at-rac.ca
Web site:  http://www.hurontel.on.ca/~weazle