Re: HV-DC Supply

Tesla List wrote:
> >From ed-at-alumni.caltech.edu Tue Dec 10 21:51:53 1996
> Date: Tue, 10 Dec 1996 17:54:36 -0800 (PST)
> From: "Edward V. Phillips" <ed-at-alumni.caltech.edu>
> To: tesla-at-pupman-dot-com
> Subject: Re:  HV-DC Supply
> Richard:
>         If you use a half-wave voltage doubler on each side of the
> neon transformer and hook the outputs in parallel (only one output
> capacitor needed) you will get the same voltage as if you used
> a bridge across the full winding.


I've noted poor overall performance with most doubler schemes over the 
years (They rely very heavily on filtering and larger than required 
series capacitances to hold the voltage up under load). 

 I actually finished my TC HV Supply system last night and ulimately went 
with the special HP defibrulator ultra-isolated HV xfrmer, with a classic 
bridge cicuit using 4 unitrode hockey puck 10KV 3amp silicon fast 
recovery units I been squirreling away.  If I blow these puppies, I'm 
immediately going to the battleship mentallity of the 673 merc vapor 
tube units!!!!  They should be OK, though.

>         By the way, that 1 ufd 20 kV capacitor is indeed something
> to blow yourself up with, as you suggest.  I remember long, long
> ago working on a CRT indicator with a guy who was really playing
> it safe.  He put a 10 meg resistor in series with the (rather high
> current) HV supply, then a 1 ufd cap to ground to get the impedance
> down!  He never could see the folly in that.
> Ed

Yeah,  Ha!  He had it backwards... one should start by making the low 
impedance supply then current limit.

Richard Hull, TCBOR