Karl-Arne said:
>It is not only the spectral purity of all oscillators involved that count, but
also the aggregated noise properties of the amplifiers and level control loops.<
I wasn't strictly considering them, but it's very true, they're another set of
limitations. There was a paper at last week's conference in London on
linearising using multiple feedforward loops, and in response to a question,
they said that noise was a problem and eventually limited the performance -
they were looking to get very good performance for multi carrier naval
equipment where one PA drives a wide band antenna with several exciters on
different frequencies.
> it is still uncommon to find better noise floors than -150 dBc/Hz at 20 kHz
> spacing
for "production" HF equipment.<
I'd have thought that was a pretty aggressive figure to meet!
So some of these parameters being paraded out these days for ham gear just
aren't applicable under other bits get cleaned up...
Still, you can kid some of the people some of the time.........
73
Peter G3RZP
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