[Elecraft] K3 on-channel strong signal overload?

[Paul Christensen]

> (In an extreme case, you could even be
> exceeding the useful range of the TR switch PIN diodes. The FT817, if
> I'm not mistaken, uses a TR relay.)

Some "scratch-paper" calculations in a 50-ohm system:

Assuming it really is the T/R PIN diodes, they would conduct at just under 
one volt.  In a 50-ohm system (and highly dependent on the PIN 
configuration), that's roughly a 10 dBm signal -- or stated another way, 10 
mW of power dissipated at the Rx front end.

It would be an interesting exercise to momentarily bypass the T/R PIN diodes 
and re-test with the same driveway setup.  So, even if this really is the 
cause, it would probably be a safe assumption that the K3 will still handle 
strong signals far better than most other receivers -- until an outrageously 
high value begins conducting PIN diodes.  That solution might call for 
replacement of the solid-state T/R with a relay.

Thanks, but "no thanks."

Paul, W9AC