From:  Malcolm Watts [SMTP:MALCOLM-at-directorate.wnp.ac.nz]
Sent:  Thursday, January 29, 1998 2:58 PM
To:  Tesla List
Subject:  Re: NEON AND SHUNTS?

Hi Chris,

> From:  Zuma [SMTP:mwise-at-ns.sosis-dot-com]
> Sent:  Wednesday, January 28, 1998 8:40 PM
> To:  tesla-at-pupman-dot-com
> Subject:  NEON AND SHUNTS?
> I posted an e-mail a while back on my 12kv-at-60ma neon that I unpotted and 
> modified. I stepped up the insulation around the primary and both of the
> secondaries. I also removed some shunts. The tranny had 4 sets of 23
> shunts, I removed 2 shunts from each set. That leaving 4 sets of 21
> shunts. In my post I stated that when I run the tranny the primary 
> heats up. It gets hot but not so hot it burns when you touch it.
> I am wondering if anyone might have an idea if this is going to be ok
> and would also like to know what kind of current this thing might be
> giving off now? I was told that it is probably just heating from the
> extra current it pushing out, which makes sense because I noticed that 
> after a while the power cord began to heat up. I don't think it is
> shorting at the primary because I had a problem once with a 15kv-at-30ma
> neon that smoked within a minute because it was shorted.
> Chris

My guess - there is no longer enough iron in the core of your 
transformer and it is saturating causing large currents to flow in 
the input wiring and primary. An isolated scope connected across a 
low value sense resistor in series with one of the input terminals to 
monitor primary current waveforms would settle the question. 
Excessive current always causes heating.