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diode protection



Original poster: "Wells Campbell by way of Terry Fritz <twftesla-at-qwest-dot-net>" <wellscampbell-at-onebox-dot-com>

hi list, 

I am working on a small MOT DC maggie, and am currently in the "advanced
cobble up"stage. Mine is of the type recently discussed, a doubler /
reactor setup, which I have been able to run at low power a few times.
As with many on our list, progress has been mainly dependent on the slow
trickle of funds I have allowed myself to put into the project. I am
at the point now where the most recent run produced 1 foot streamers
into open air, and I was able to sucessfully control power by varying
the break rate on my ASRG, which pleased me greatly. The sound was cool
too, somewhat like a whiny siren that changed up and down as I dialed
my variac. 

Then my cap (party plates in oil in a bucket, very crude) popped. Time
to get out the salt and foil and drink some beer!

then my MOT reactors started to flash over (naturally, they aren't in
oil or anything) and my PS started to eat diodes which (naturally) aren't
protected or anything. 

Anyway, I'm satisfied enough with results so far to start putting together
the final version, and I had a few questions. 

Does anyone have any advice on a diode protection filter arrangement?
I like Greg Hunter's arrangement, I thought I would use those 10kv /
.001 uFd ceramic caps at all electronics, one in parallel with each (MO)
diode. Is this too much capacitance?  

Then I was thinking of using a pair of power resistors after the de-Q-ing
diodes and before the reactors (one per HV leg) to attenuate spikes from
the reactors, as well as those from any flashovers that may occur in
the future. What would be a good value? 1k ohms? 100 ohms? Also should
I use chokes too for an LCR  network, or should I not bother because
the reactors serve this purpose? what about a safety gap? where would
it go? seems like anywhere i put it it would power-arc.
Any advice would be helpful before I pour tens and tens of dollars into
components :>)

My shematic is similar to the one on Greg's site, "speculative DC reactor
setup". I will post pics and details soon, but feel I should make a little
more progress first. My power switch is still an old power strip and
a bamboo chopstick (i'm not gonna touch that thing!) :>)

Also, a filter that instantaneously clamps outflow of funds as exuberance
begins positive cycle would be helpful.  

Cheers,

-- 
Wells Campbell
wellscampbell-at-onebox-dot-com