Rectifier/NST Protection

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

Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" <MaverickIce00-at-aol-dot-com>

Hi all!, 

I have some questions concerning a full wave rectifier connected to the 
output of a NST and how it compares with an RC Filter like Terry's. 

1) Would the rectifier eliminate any need for the filter array? I believe it 
would, since diodes only allow current to pass through in one direction. I'm 
already planning on building a filter regardless, but I thought it would be 
fun to throw in a couple hundred diodes with my order to Digi Key in a couple 
of days. 

2) What are suitable diodes for this application? I have already narrowed it 
down to the 1N4007--- line, but there are 4 pretty cheap ones that look like 
they might just work. They are: GCT, DICT, MSCT, and GICT, if there is any 
important distinction between them (besides cost)? I'd rather go with the 
cheapest ones (which are 1N4007GICT -at- $0.032 a piece, they're normal silicon, 
compared with silicon rectifier for DICT & MSCT (if there's any difference) 
and glass passivated (whatever that is :-))for GCT. I'd like to steer clear 
of the glass stuff (it's more expensive -- $0.104 a piece 8^0)and since 
there's only a $0.002 difference between the last three, I can afford to 
drift :-) 

3) How 'immune' would a 20 kV rectifier be against the RF of the primary 
circuit? RF is always destroying NSTs and I though that maybe something 
similar might happen with a rectifier of this type. 

I would basically wire at least 20 in series (6 kV tranny) for each leg of 
the transformer, giving a safety factor of about 2.3 (should I go higher?). 
Using the advice from Sundog and others, I would include a 10 megohm, 1/2 
watt resistor between each diode, for added safety. It has also come to my 
attention that the tank capacitor will still be fully charged after the power 
has been removed with a DC power source, but won't the resistors in the MMC 
just bleed off any charge? Thanks ahead of time! I'll be sure to have some 
more questions later as I continue building my TC. Whoa, 1 AM... better get 
some more coffee... :-) 

Happy Holidays! 

- Josh Hunsaker - 

Denver, Colorado 
Email/AIM: MaverickIce00-at-aol-dot-com 

BTW: I found a couple of guys who 'think' they might have a suitable tranny 
for me, and with any luck, I should have a tranny by the end of this week, 
although it will be tough, with the holidays just around the corner...