Hi, Jim.
Thanks for the nice explanation. I really finally 'got it' when you talked
about the actual dBm. I now know that if I am trying to receive a weak signal
on 160m, and a S9+60 (-13dBm) signal is on an adjacent frequency, I will be
able to hear a signal near the MDS of my Omni VI+ (at 5kHz). (Yeah, but what
about the rock crusher that is only 750Hz away?...guess I need to measure it...)
Anyway, the reason I responded is to ask you to elaborate on the IMD. Can you
explain IMD in terms of dBm? If I have a receiver spec of, say, +20dB IP3, and
an IMD3 of 100dB, what does that mean in terms of actual signals? Can you
explain using my real world 160m example. Let's say two S9+60dB signals mixing
into my passband. How strong would the resulting spurious signal be?
Thanks!
Marty Ray, N9SE
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