Hi!
For some hours now I'm sitting in front of the computer, modelling a new and of
course much much nicer :) preselector-filter for 500kHz. With a 3-inductor
nodal capacitor-coupled bandpass, a 12kHz passband seems to be a good tradeoff
beetween insertation loss (2-3db), passband ripple (1db) and shape (-24db at
518KHz, -43db at 531kHz).
So far I haven't noticed any transmissions below 500.000kHz (SK6RUD) and above
abt. 507kHz (Gus' SSB-Tests).
So I ask myself and now You :) , would You say it's important to keep the full
rx range from 495kHz to 510kHz and pay the price of a worse stopband
attenuation, or do You think, it's unlikely to hear any transmission at the
band corners?
vy73
Dennis
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