Had a good trial run on 222 after repairing my Larcan SSPA:
K1WHS FN43, W1GHZ FN34, KA1OJ FN42, WB2VVV FN41,
N1SV FN42, W9KXI FN12, K1PXE FN31, WA2LTM FN20,
WA3NUF FN20, W1XR FM19, WA1PBU FN42, K2RMX FN20,
WC2K FM29, WA1MBA FN51, WA3EOQ FM09, K1FSY FN31,
AA2SD FM29, WA1RKS FN32, KC2SGV FM29, W1AIM FN34,
W1AIM FN34, WA3DRC FM28, and an almost Quansheng contact
with KC2KAE/QRP FN20. Frank was in the noise but it was close.
What I learned from all this is that these protection circuits work
great for load faults, but do nothing for internal circuit failures
like a chip cap going up in smoke in the Drain RF circuit.
Also one of the FETs proved to be a much faster acting
fuse than those glass fuses Larcan uses to protect them.
But not fast enough to stop the board from getting charred.
Now I know why there's so many failed MOSFET and LDMOS
amps being sent back for repairs. Why not spend a bit more
on lower ESR caps, because that would hurt their repair business.
73 and TNX Ron WZ1V
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