Re: Magnifier questions

>The magnifier requires a really special gap system.  The coupling between 
>the pri/sec in a magnifier is about 8 times that of a normal small coil 
>so breakdown between primary secondary is normal.  To prevent this, you 
>can reduce the coupling a bit, drop the whole thing in oil or insulate 
>with many turns of thick polyethylene sheet wrapped against the inside of 
>the primary.  This wrap must extend well beyond the top of the primary 
>almost to the top of the secondary.
>Finally the tune on the primary is often the lumped tune of the secondary 
>and resonator combined!
>Richard Hull, TCBOR

In what way is the spark gap different?  Is there some info on this somewhere on
the net?

Also if the resonant frequency of a magnifier is the lumped tune of both coils then
the voltage rise must be greater in the first coil (in volts per turn) than in
the resonator due to standing wave 1/4 wave.  Current being 90 degrees out of phase
with voltage and current at a maximum means large gradiant in voltage.  I assume it
is better to generate the voltage in the resonator if insulation problems are to
be overcome.  So i'll wind the secondary driver from thick wire.  Abit of a balancing
act this, working out a good impedance match between driver and resonator.

Julian Green.