[Elecraft] Need a Fuse on the K3's Power Line?

[Jarmo Blomster]

If you do not have fast fuses in 12V DC wire you may end up with loose and
broken PCB traces in RF board, also the connectors can be damaged.

I bought a used K3 #6913, the seller said that he had messed the polarity
with car battery. That caused a major circuit board problem in the trace
that lead to KPA3 in RF board. The seller had fixed the problem temporarily
but it really need better fixup to keep it working.

He hadn't put fuses in the DC wires as the manual suggest, maybe he just
trust the 20A circuit breaker of the KPA3. Obviously that is not adequate
protection. Maybe also Elecraft engineers can do something to the reverse
polarity protection to make it more robust, to my mind the protection is
not adequate if it results loose PCB tracks, eventough support so claims.
At least Elecraft should supply fast fuses in the 12V DC line to prevent
other damages, maybe a humble manual note is not enough.


Here is a picture of what is the result if you don't have the fuses in
place.
https://plus.google.com/photos/103676169039107946672/photo/5889028521722277378

73 de OH9VD/Jarmo