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Re: Rotary Spark Gap


>Jim;  
>  I haven't seen any responses to this one yet, though I suspect that some 
>of my mail gets dropped somewhere. My apologies if this has already been 
>answered. 
>
>  A quickie back-of-the-envelope calculation shows that the 995H inductor  
>has such a high impedance compared to your load resistor (more than a 
>couple orders of magnitude) that the load resistors shouldn't have any  
>significant effect on the current, and that the current computed is about 
>right. The current deduced from your voltage measurement across the load 
>resistor is just about exactly what you've computed, so that should make 
>you feel good. The only inconsistency is the 0uA current measurement. 
>
>  I haven't seen your apparatus, but the fact that you were able to make  
>a measurement that does agree with the computed value would lead me to  
>first suspect that the ammeter mode in your multimeter isn't working. 
>Have you tried it in some different setup to verify that it's OK? Also, 
>some multimeters only have a DC current scale. Is this the case, or  
>could you have possibly set things up to measure DC current instead of 
>AC? It would seem that a reading of somewhere in the range of 0uA would 
>be correct there, too. :-) 
>
>Wes B. 
>
Wes,
        I had a few responses, so you may want to check your mail reliablilty.

        I've come to the conclusion that both my multimeters do not measure
AC milliamps.

        I called magnacraft today, they bought Jefferson Electric whom made
one of the neons xfrms that I now have, the products specialist that I
talked to confermed that from a static current standpoint, a shunt limited
transformer could be treated as a perfect transformer connected in series
with a large inductor. It does not resonate as if It has 995H of inductance
in series with it. He could not give me a secondary inductance value, even
thought I asked him 3 times.

                                        jim