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Re: flyback TC



> 3. Ihave calculated the output of a cascade multiplier with 60 stages to
> be at least 6kv and 60ma(1kv drop).  Is there any reason for this not
> working for a TC?

60 stages? Running off 110V input to get 6 kV, presumably.  Did you take
into account the forward voltage drop and IR losses of the rectifiers.  It
is quite difficult to get a 60 stage multiplier to work. The frequency will
need to be quite high to get 60 mA out, or the caps will need to be fairly
large.  Don't forget that the current in the caps on a multiplier stack is
significant (well at least 60 mA average, in your case, and much higher
peak, particularly at the top stages). 

However, if you have lots of spare time to do the assembly and you've got
the caps and diodes, it is worth a try.

I assume you'd you running an resonant charging scheme with an inductor and
a diode to charge the tank cap? Don't forget it takes many, many cycles of
the input for a multiplier to reach nominal output voltage (on the order of
2N cycles for a half wave multiplier)

Just from a construction complexity standpoint, you are probably better off
finding a surplus HV transformer. Cost is an issue too, 1N4004's would work
for the diodes and be cheap (for running off 60 Hz), but the caps might not
(of course, you could use surplus photoflash caps from disposable cameras,
which you can get for free)