[Amps] please help with weird problem - culprit found

[Joe Subich, K4IK]

> From: Floyd Sense
> 
> The situation with the receive antenna input is well known 
> among Icom 765 users who operate on 160.  KD9SV makes a nice 
> little protection unit that can be used with the 765 and any 
> other transceiver with a separate receive antenna input.  It 
> grounds the receive input on the rig as well as disconnects 
> the receive antenna during transmit (controlled by your PTT 
> line).  Here's a link for those interested
> http://www.radio-ware.com/products/fes.htm .  

Not only is the "problem" well known with the 765 ... it exists 
in all of the Icom radios, the Yaesu FT-1000 series radios, and 
most other rigs that provide provisions for either an external 
receive antenna or transverter.  I have seen feedback and/or 
damage related to the use of external receive antennas, SO2R 
operation and/or multi-transmitter contest operation since the 
late 70's (Drake TR-7, Kenwood TS-830, etc.).  

These issues are some that the top SO2R and multi-op station 
designers take extreme care to avoid. 

73, 

   ... Joe, K4IK