Re: Fair caps test

Hi Robert,

(from Robert W. Stephens reply to the Fair cap test)
>I think that the conclusive test 
>will be in an actual tuned Tesla coil that has been used tuned with 
>capacitors of known quality previously so that the spark ouput length 
>can be used as a performance gauge. 

Good idea.  It would be interesting to try this with other commercial caps.  My
flat plate cap was pretty anemic, and almost anything would have been an

>If this capacitor 
>were the desired polypropelene in silicon oil, there would be no 
>detectable dielectric heating from your test, although the terminals 
>might still get warm.  

Ahh...now that's the type of thing I was wondering about.  Having only run my
own homemade caps before, I don't have much to compare the Fairs to.  Your
point about the delay in heat transfer from the inside to the outside of the
cap makes a lot of sense too.  It took quite a long time to cool down

>As I recall, these capacitors were quiite expensive, was it $100.00 
>for a 0.01 mfd?

Yes, they are expensive.  As I was mentioning to another person here, when you
compare them to new CP caps, the price is not very competitive.  Particularly
when considering how many you'd need.  I just got a bit impatient waiting for
the CP group order to be resolved, while blowing holes in my flat plate cap. 

>Finally, I am suprised that your neons did not fail during the test 
>as described.  You were feeding some whicked high frequency RF back 
>into those fragile transformers, apparently without the protection of 
>series RF isolation chokes.

I did have a pair of big air core chokes on the neons.  Sorry...forgot to
mention that!   

>the high EMI field in the vicinity of the capacitor in the test you described
may well 
>permanently scramble the delicate electronics of the thermometer.

I've seen it happen several times to watches, kitchen appliances, etc.  I was
thinking more in terms of measuring temperature after the test.

Thanks for the comments!

Charles Brush