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Re: Rotary Sparkgap

Further to my neon addendum and in reply to Jim Fosse...

>         I haven't digested all of your post from yesterday yet, so I haven't
> responded to it yet. But today I did call magnacraft (old Jefferson
> Electric) to ask about their Neon transformers. Their product specialist
> said that you could treat the neon as a perfect transformer in series with a
> large inductance for "DC" only. It will not resonate as if it had a 637H
> inductor in series with it, to use your numbers from yesterday. So I guess
> we don't have to wory about the current of a series resonant circuit going
> to 360ma or the voltage going to 36KV.

I've reached the conclusion that the low-level Q I measure is 
different from the powered-up Q. But it most certainly ddoes resonate
at low-level, and at least three people here have encountered diffi-
culties associated with resonances under normal running conditions.  
I think the 360mA IS invalid. BUT, any resonance implies a higher
current than the limited value into a resistive load. I have opened
up a spark gap to well over the rated peak voltage and I know Ed
Philips has too.

> If I remember correctly, the leakage inductance of a transformer is 
> measured by shorting the secondary and then measuring the 
> inductance of the primary.

Shorting the primary should achieve the same end as shorting the 
secondary IMHO. The idea of using a low-Z generator was to achieve
exactly that.

> If you have an inductance bridge available (I don't) could you measure your
> transformer, primary, secondary, and leakage? It would help some of
> us-old-stumbling-EEs to get back to first principals;)

Looks like I have the same problems myself at times ;)  No, I don't
have a bridge that can handle the beast. I reiterate that I think
the resonant f idea (forget the Q one) is valid for finding Xl.
BTW, the primary resistance is less than 2 Ohms. Total core sat-
ration would spell death for primary fuses.

Regards,
Malcolm