reason for rf chokes?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Laurence Davis by way of Terry Fritz <twftesla-at-qwest-dot-net>" <meknar-at-hotmail-dot-com>

I had an EE friend of mine interested in my coil.  when i drew up the 
schematic (at his request), he seemed confused by the chokes I use to filter 
the high frequency from the tank circuit.

I explained that due to the skin effect, the 200khz signal causes the
secondary windings to overheat, thus the need for the chokes.  I'm guessing 
here, but when the tank cap dumps its charge to the primary there is voltage 
spike that returns several times during ring down.  This spike returns to 
the choke, which dampens the spike.  The choke is essentially transparent at 
60hz, but highly resistive to the 200khz signal.

does the voltage return or is it a current spike?

i thought it would be neat to connect a scope to the hv voltage side just 
after the choke and before the cap.  but i dont want to fry a nice scope 
soooo how about a faraday cage around the scope and optocoupled probe? (like 
i could pull that design out of my hat or something!)

so, how far off track am i?

larry.

_