Paul Burridge wrote:

Can someone kindly confirm what the hell "IP3" is?? I can only think
of "3rd order intermodulation products" which might easily be
completely wrong. It would be helpful if whoever first uses an
uncommon abbreviation would have the courtesy to state what it meant!
(as is customary first time around)
snarl, hiss, etc

I agree it's discourteous to use an uncommon abbreviation without
explanation. But IP3 is a very common abbreviation when discussing mixer
or receiver performance, and it's reasonable to assume that anyone more
than superficially involved in receiver or mixer design or application
has at least heard the term. Or that they can at least do a simple
google search. (It really doesn't take any more time than making an
angry newgroup posting!) A google search of "IP3 mixers" brought about
2500 hits. I'm sure that if you read one or two of them, you'll get the
idea.

Roy Lewallen, W7EL