Tom Rauch wrote:
I agree with Mike on this.
IP3 for a number of reasons is useless for determining anything useful.
Ignore it.
I'd look only at the IMD dynamic range. The Omni 7 doesn't look too bad.
While it is not exceptionally good, it most certainly isn't bad.
73 Tom
Finally, something we completely agree on. You can increase IP3 on the
world's crappiest receiver. If you have a -20 dBm IP3, you can
increase the IP3 of that receiver to +40 dBm by putting a 60 dB
attenuator in front of the receiver. The receiver would practically
useless but the Ip3 would be great. Of course, you have decreased the
sensitivity or increased the noise floor by 60 dB!
IP3(dB_Hz) (measured relative to the noise floor in 1 Hz) would be
useful but we get to know most of what we want from looking at IP3, BDR,
and IMD-DR with the last number, the dynamic range, being by far the
most important of the three.
Bob
N4HY
--
AMSAT Director and VP Engineering. Member: ARRL, AMSAT-DL,
TAPR, Packrats, NJQRP, QRP ARCI, QCWA, FRC. ARRL SDR WG Chair
"If you're going to be crazy, you have to get paid for it or
else you're going to be locked up." Hunter S. Thompson
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