At 11/27/2009 18:19, you wrote: > > > >Yep, but the GLB trailing tuned circuits would also > > >improve the realized GaAs Fet device equipped 3rd > > >order performance... as would properly set cavities > > >between a pre-amplifiers output and the receivers > > >input. > > > > No, they don't. They only improve the 3rd order > > performance of whatever is downstream. > >Bingo... but also in reality the trailing filters >would also contribute toward the preamplifiers 3rd >order performance.
There is a way to prove the above: measure the P1dB (or the 20 kHz 2-tone IMD response) of the GLB as a function of frequency. If it tracks the overall gain curve of the unit, then you're right. However, I'd expect the above response to be considerably wider, tracking the response of the input filtering only. Bob NO6B
