Re: Where to get high voltage diodes?

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

Original poster: "Richard Williams by way of Terry Fritz <twftesla-at-qwest-dot-net>" <richardwwilliams-at-earthlink-dot-net>

Hi List,

I bought 50 HV diodes from Moteva for my DC power supply. Unfortunately they
have a minimum order of $50. In my case though that wasn't much of an issue
since I wanted a lot of these anyway. With 40 of them I constructed a 60Kv
full wave bridge at 1 amp, two strings of 5 in each leg. Haven't checked or
tested about the current dividing unevenly per leg because of the slightly
different forward voltage drops across the diodes but I'm only running 100ma
right now anyway.

http://www.moteva-dot-com/moteva/main_page.html

THV512T
Most Popular Microwave Diode
SPECIFICATION 12KV 550mA
REPLACEMETN FOR HVR-1X-3 and HVR-1X-4

1-24 $1.20
25-Up $0.99


Rick Williams
Salt Lake City

----- Original Message -----
From: Tesla list <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Wednesday, August 29, 2001 5:18 PM
Subject: Re: Where to get high voltage diodes?


> Original poster: "Steve Cook by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<steve-at-g8cyerichmond.freeserve.co.uk>
>
> I use strings of 1N4007's which are good for 1kV -at- 1amp, for 10kV I use 15
> in series, no equalising resistors, they are not needed and are a serious
> cause of probs. I then coat the whole with epoxy or hot melt glue.
> ----- Original Message -----
> From: Tesla list <tesla-at-pupman-dot-com>
> To: <tesla-at-pupman-dot-com>
> Sent: Monday, August 27, 2001 7:04 PM
> Subject: Where to get high voltage diodes?
>
>
> > Original poster: "Garry F. by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <garryfre-at-pacbell-dot-net>
> >
> > About six months ago (It seems a year), I paid someone on the list for a
> > high-voltage rectifier circuit. They had made an MMC for me and it works
> > excellently, and they were talking about how I could have DC voltage and
> > have an assync gap and I also thought this would be great for preventing
> > voltage ring-up and so I took them up on the offer and to my
> dissapointment,
> > the circuit has never been forthcoming. ;-( I mentioned it three times
and
> > I've decided to give up for two reasons ....
> >
> > #1 The fellow sent me an MMC that was worth far more than I paid for it
> even
> > worth more than what I paid for the MMC after adding in what I paid for
> the
> > rectifier.
> >
> > #2. The individual is just flaking out and I don't want to be a pest
about
> > it any more. He hasn't even cashed the money order.
> >
> > I guess this further makes the point that for the most part we can trust
> > each-other to deal honestly with each-other, *but* we are still human
and
> > some of us tend to put things off, sometimes forever.
> >
> > I hope this note to the list will motivate the person to either build
the
> > thing or just come out and say they haven't the time to build it but I
> won't
> > be holding my breath.
> >
> > This still leaves me without a rectifier and I could just guess around
as
> to
> > what parts I need, or I could ask here and make sure I get tried and
true
> > parts. (Remember the exploding MMC dabacle?)
> >
> > I remember I need diodes in wheatstone config, but I think I am
forgetting
> > something else.
> >
> > The NST is a 12kv/60ma nst. Has anyone any suggestions on parts to get
and
> > how many of these diodes to  put in series? I would guess I would want
at
> > least 15kv of diodes to make sure I have some buffer, but I don't know
> about
> > current. Maybe I need several in parallel to distribute the current so
as
> to
> > reduce over-heating. I just don't know and I don't want to guess around
> > because I think I would be doomed to guess poorly.
> >
> > Thanks in advance.
> >
> >
> >
> >
>
>
>