Rich Measures wrote:
> IMO, adding more words is not always better, Ian--unless one is
>getting paid by the word! Adding to Ken Stewart's well-worded statement
>on page 11.9 in the ARRL Handbook seems like gilding a lily.
Well, the extra words were essentially Ken's own, and he was happy to
provide them. The key piece of additional information was that older
rectifiers broke down in a destructive arc, but modern ones break down
in an avalanche mode that doesn't have to be fatal.
>bottom-line is that rectifier "equalizer" resistors can CAUSE reverse
"...because they can produce a low-impedance source of damaging current
to any diode that may have reached avalanche potential." (W3VVN)
>The puzzler is why did Mark Wilson and David Sumner publish 1200 words in
>the 9/94 issue of *QST* which contradicts what Ken stated in the
Rich was entitled to be puzzled about that.
As an afterthought to my previous posting, it's worth noting that the
K2AW 14kV diode strings are generally being used at only 25%-30% of
their PIV rating. Their reliability proves the point: the surest way to
avoid diode breakdown is use lots of them - PIV is cheap!
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
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