[Elecraft] K3 RX protection

[brian]

Really screwed up.  I was using a pulse generator (5 V, 50 ns wide, 10 
milliseconds between pulses) to look at the health of the antennas/coax.

Connected it to the wrong coax.  Result it went into the K3.

First indication something was wrong: The the scope traces looked goofy.

Oh ###!!!!

Happy to say the K3 appears to have survived without apparent damage.

Don't do this at home.

73 de Brian/K3KO