Hi Jim,
>1. The IP3 data posted at the Ten Tec web site, the
>curve for the Orion, was collected with the two strong,
>intermodulating test signals OUTSIDE the roofing filter
>pass band!
>
I wonder about using that word "intermodulating" the way you have.
Please correct me if I am wrong, because I want to understand this. It
is my understanding that the test setup is such that the two signals are
generated by separate signal generators, and are combined through
appropriate attenuators and power combiners so that there is no (or at
least very little) non-linear mixing going on in the output stages of
the generators or anywhere else, except in the radio being tested.
Intermodulation products created in the radio (in this case the stages
before the roofing filter) are what we are intending to measure. If the
signals are "intermodulating" it is in the radio under test, and that is
what we are attempting to quantify.
Ken N6KB
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