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Converting diodes to resistors



Original poster: "S & J Young by way of Terry Fritz <teslalist-at-qwest-dot-net>" <youngs-at-konnections-dot-net>

Semiconductor failure experts,

I fried (over easy) a string of  15 1N5408s in my DC resonant charger power
supply.  Usually I have the spark gap across the supply & resonant choke and
the cap in series with the primary.  But I noticed in Richie Burnett's site
he showed the cap across the charging power supply and the gap in series
with the primary.  So I tried it.  BIG MISTAKE!  The RF caused a smoky and
stinky voltage breakdown in one of the MOTs I used for the charging
inductor.  The RF also wiped out a diode string.

Question:  The diodes all still have the usual forward characteristics, but
the reverse resistance on all of them has gone from higher than 200 megohms
when they are good, to around 12K.  They vary from 5 K to 20 K.  So, just
curious, what did the RF do to the diode junctions to make them act like
resistors?

--Steve Y.