>Has anyone had a chance to play with the ICOM 756-PRO??
I'm told it's good. How good, I don't know.
24 bits sounds good, but I guess it's at low frequency. Figure you want one
bit toggling on internal noise, and two bits at the top end to handle the
fact that the ADC has to handle the peak voltage, not the rms. This gives
you a theoretical 126dB range from noise floor to overload (AGC doesn't
apply because you've got to handle signals outside the bandwidth of the AGC
loop) which should be pretty good. But the analogue circuitry prior to the
ADC has got to be able the handle the signals without distortion and feed
the ADC at a level and frequency such that its noise doesn't dominate. So a
crystal filter probably gets needed to protect that circuitry.
It seems peculiar to me that every 'advance' in receiver technology that
I've seen in the last 40 years (and I'm only 53) has always initially
produced worse performance than the old technology it was supposed to
replace. Eventually, of course, the advantages shine through.........
73
Peter G3RZP
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