Hi Vic, from 1996 ARRL Handbook, DIODES IN SERIES, page 11.9:
"There used to be a general recommendation to place a resistor across each
diode in the string to equalize PIV drops. With modern diodes, this practice
is no longer necessary." It goes on to explain why then concludes with:
"In fact, shunt resistors can actually create problems..." and why again.
The 1N5408 qualifies. I use 16 of these in each leg of a fullwave putting
out 4KV - no probs.
73, Bill N2BC
-----Original Message-----
From: Vic Rosenthal <rakefet@rakefet.com>
To: Amps reflector <amps@contesting.com>
To: <amps@contesting.com>
Date: Saturday, July 03, 1999 11:49 AM
Subject: [AMPS] PS diode equalizing
>
>What's the current view on equalizing caps and resistors across diodes in
>rectifier strings? The ARRL handbook says you should put a 0.01 mf
capacitor
>and (I think) 1000 ohms per volt resistor across each diode. I dimly
recall a
>discussion in which this was said to be *not* advisable. I'm using 5
1N5408's
>per leg of a fwb with 2400 vac input.
>
>73,
>Vic, K2VCO
>Fresno CA
>
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