[TenTec] New Sherwood Presentation - Powerpoint & Audio

[Alfred Lorona]

Terry, N4TZ/9  has touched on an important point that has long been a 
priority on my list of receiver specifications that are relevant and those 
that are less relevant. Two tone IMD is not at the top on my list. A related 
parameter which is similar but not identical is receiver desensitization. 
This requires only one off freqeuncy signal, not two. And there is not a 
precise frequency requirement as with two tone IMD. In adddition, I have 
also noticed that often a still more pernicious phenomena is transmitted 
broadband phase noise. Several field day operations have been ruined 
primarily by these two types of interference and not two tone IMD. I also 
wish to add that two tone IMD is more serious on CW becaue both signals are 
always transmitted at full power. On the other hand, with SSB, both 
transmittiers must hit peak power simultaneoulsy for a third order product 
to be generated in the receiver. Due to the instantaneous peaks of speech 
that occur at a sporatic manner, the probability of this happening is 
greatly lessened and when it does happen, the interference is an extremely 
short spurt.

73, AL, w6wqc