I am having some difficulty finding a bridge rectifier of 3 Kv and 3 amps.

??

thanks
greg
N6GS

On Apr 11, 2:41 pm, (GregS) wrote:
I am having some difficulty finding a bridge rectifier of 3 Kv and 3 amps.

??

thanks
greg
N6GS

Make your own, from single diodes. 1kv at 3 or 5 amps are easy to
find.

The ARRL handbook might be helpful for building you own. You might also
try Peter Dahl. Here is a link to his rectifiers.
http://www.pwdahl.com/dahlcatalog/WEBCLISTU.pdf


GregS wrote:

I am having some difficulty finding a bridge rectifier of 3 Kv and 3 amps.

??

thanks
greg
N6GS



--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P

Also do not forget load sharing resistors and bypass caps...
"GregS" wrote in message
...
I am having some difficulty finding a bridge rectifier of 3 Kv and 3 amps.

??

thanks
greg
N6GS

Hi Greg,

In addition to Joe's suggestion, Linear "Amplefire" guru Richard Measures
talks about rectifiers he http://www.somis.org/D-amplifiers3.html
For reasons of heat-dissipation (and I expect also cost), he's not too fond
of the epoxy-encapsulated HV rectfiers -- he prefers to build his own stack
on perforated circuit board. If you want to heed his advice, you could
build a reasonably tidy bridge with a dozen 1N5408 (3A/1KV) rectifiers.

73,
Bryan WA7PRC

Joe wrote:
The ARRL handbook might be helpful for building you own. You might also
try Peter Dahl. Here is a link to his rectifiers.
http://www.pwdahl.com/dahlcatalog/WEBCLISTU.pdf


GregS wrote:

I am having some difficulty finding a bridge rectifier of 3 Kv and 3
amps.

??

thanks
greg
N6GS



--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

It would be wise to NOT use load-sharing (aka equalizer) resistors &
capacitors. With modern rectifiers, if more than one diode is in a string,
there will be no problem as long as they are of the same type number. See
http://www.somis.org/D-amplifiers3.html.
73,
Bryan WA7PRC

P.Gregory wrote:
Also do not forget load sharing resistors and bypass caps...
"GregS" wrote in message
...
I am having some difficulty finding a bridge rectifier of 3 Kv and 3
amps.

??

thanks
greg
N6GS

Wise?
I could put just as many links saying the opposite , as in series , Not
parralel and not paraletic , few few ohms aint gunna do what you yanks say
"diddly squat" unless you get perfect diodes , read as matched ..paul



"Bryan" wrote in message
...
It would be wise to NOT use load-sharing (aka equalizer) resistors &
capacitors. With modern rectifiers, if more than one diode is in a
string,
there will be no problem as long as they are of the same type number. See
http://www.somis.org/D-amplifiers3.html.
73,
Bryan WA7PRC

P.Gregory wrote:
Also do not forget load sharing resistors and bypass caps...
"GregS" wrote in message
...
I am having some difficulty finding a bridge rectifier of 3 Kv and 3
amps.

??

thanks
greg
N6GS

In article , "P.Gregory" wrote:
Wise?
I could put just as many links saying the opposite , as in series , Not
parralel and not paraletic , few few ohms aint gunna do what you yanks say
"diddly squat" unless you get perfect diodes , read as matched ..paul



"Bryan" wrote in message
m...
It would be wise to NOT use load-sharing (aka equalizer) resistors &
capacitors. With modern rectifiers, if more than one diode is in a
string,
there will be no problem as long as they are of the same type number. See
http://www.somis.org/D-amplifiers3.html.
73,
Bryan WA7PRC

P.Gregory wrote:
Also do not forget load sharing resistors and bypass caps...
"GregS" wrote in message
...
I am having some difficulty finding a bridge rectifier of 3 Kv and 3
amps.

??

thanks
greg
N6GS

I think I am willing to try using them without caps and resistors.
I allready have 1KV 3 A HER308's. And I have a bunch of thermal
epoxy. I just might purchase some of these to make things easier.

http://www.fairchildsemi.com/ds/FF%2FFFPF04F150S.pdf

greg

GregS ) writes:
In article , "P.Gregory" wrote:
Wise?
I could put just as many links saying the opposite , as in series , Not
parralel and not paraletic , few few ohms aint gunna do what you yanks say
"diddly squat" unless you get perfect diodes , read as matched ..paul



"Bryan" wrote in message
om...
It would be wise to NOT use load-sharing (aka equalizer) resistors &
capacitors. With modern rectifiers, if more than one diode is in a
string,
there will be no problem as long as they are of the same type number. See
http://www.somis.org/D-amplifiers3.html.
73,
Bryan WA7PRC

P.Gregory wrote:
Also do not forget load sharing resistors and bypass caps...
"GregS" wrote in message
...
I am having some difficulty finding a bridge rectifier of 3 Kv and 3
amps.

??

thanks
greg
N6GS

I think I am willing to try using them without caps and resistors.
I allready have 1KV 3 A HER308's. And I have a bunch of thermal
epoxy. I just might purchase some of these to make things easier.

http://www.fairchildsemi.com/ds/FF%2FFFPF04F150S.pdf

greg

The parallel resistors and capacitors in parallel with series diodes
dates from the early days of semiconductor diodes.

The resistors were there to "equalize the reverse voltage drops".
The diodes back then weren't particularly great, and there were worries,
I can't remember if real or imagined, that the diodes couldn't handle
the reverse voltage they'd see. The diodes were there to make sure each
saw the same reverse voltage.

The parallel capacitors were to protect against spikes. Again at a time
when there was real or imagined worry that the precious semiconductor
diodes would be easily damaged.

This was the same period that would always warn about heatsinking the
leads of semiconductors when soldering them, to protect them against
heat.

YOu'll see this talk of parallel resistors and capacitors with the
use of series diodes in older handbooks and magazines, and then it fades
away. I doubt it will hurt anything, but either the diodes got better (in
those early days one often had no choice but to put some diodes in series
just to handle average B+ voltages, let alone outright high voltage), or
the whole thing was an illusion, and wasn't actually needed.

Series resistors limit the current, to protect the diodes against current
surges. The 1971 ARRL Handbook says you need them if the winding resistance
of the transformer are too low to do the limiting itself.

Michael VE2BVW

GregS wrote:
P.Gregory wrote:
Wise?
I could put just as many links saying the opposite , as in series , Not
parralel and not paraletic , few few ohms aint gunna do what you yanks
say
"diddly squat" unless you get perfect diodes , read as matched ..paul



Bryan wrote:
It would be wise to NOT use load-sharing (aka equalizer) resistors &
capacitors. With modern rectifiers, if more than one diode is in a
string,
there will be no problem as long as they are of the same type number.
See
http://www.somis.org/D-amplifiers3.html.
73,
Bryan WA7PRC

P.Gregory wrote:
Also do not forget load sharing resistors and bypass caps...
GregS wrote:
I am having some difficulty finding a bridge rectifier of 3 Kv and 3
amps.

??

thanks
greg
N6GS

I think I am willing to try using them without caps and resistors.
I allready have 1KV 3 A HER308's. And I have a bunch of thermal
epoxy. I just might purchase some of these to make things easier.

http://www.fairchildsemi.com/ds/FF%2FFFPF04F150S.pdf

greg

The HER308 looks like a 1N5408 with a specified reverse recovery time. I
like specifications those FFPF04F150S damper diodes. Digi-Key has them
available in only large quantities (non-stocked) but Mouser shows them
in-stock in small lots. Not knowing the dielectric capability of the plastic
TO-220 case, I'd probably mount them (with heatsinks) to an insulating base.

Bryan