[TowerTalk] receiver protection

[Joe Subich, K4IK]

> I am looking at a design for receiver protection in an
> SO2R environment that involves a series resistance (#49 
> bulb) and stacks of back to back diodes shunting the receiver 
> input.  The objective is to protect front-end components 
> against strong out-of-band signals, but in the process I 
> don't want to incur an intermod penalty under normal operation.

20 years ago or so DEO (the QSK-1500) had a receiver front-end 
protector that was a Chicago Miniature #12 lamp in the receive 
line followed by a back to back pair of either two or three 
1N4148 diodes in series (can't remember and don't have one to 
take apart) ... lamp was between the diodes and the antenna. 

ICE shows a receiver protector - I don't know what they have in 
it.  See: 
http://www.arraysolutions.com/Products/ice/reconly.html#rflimiter

73, 

   ... Joe, K4IK