Couldn't help adding my two cents here.
I must agree with John's original comments - based on "conventional RF design wisdom" the bandwidth of a 10.7MHz IF is generally much less than +/- a few hundreds of kHz. Unless something unusual is going on there will likely be real problems with adjacent channel interference.
A snippet of the ar5000e.html URL cited above by Krzysztof follows:
"The receive circuitry is a triple conversion superheterodyne with IFs of 622MHz, 10.7MHz
& 455kHz. Multiple switchable IF bandwidth are available in both the 10.7MHz and 455kHz IF
stages: 3kHz, 6kHz, 15kHz, 30kHz, 110kHz, & 220kHz with provision for an optional 500Hz
Collins mechanical filter."
These values make sense for a communications receiver. There are three
sequential IFs (good design technique but can be a bit pricey) and the
bandwidth specified for the second and third IFs is quoted in the tens and
hundreds of kHz. Again, it is unlikely that the hundreds of kHz bandwidth
values are available at the third IF (455kHz) but more likely available from
the a tap of the second IF (10.7MHz).
As Krzysztof also notes there is a quote on the page referenced by the same URL
which follows:
"The AR5000 is ready to plug straight into the optional SDU5500 spectrum display unit for
"real time" band occupancy evaluation and measurements in both frequency and dBm signal
level. The 10.7MHz I.F. output of the AR5000 has a suitable 10MHz bandwidth ideally matched to the
SDU5500."
Now this is really curious. I would not be surprised to see a 10MHz bandwidth
available from the *first* IF (622MHz) but am dubious of the claim as written.
It *is* possible but would be highly unusual.
Need to look into this a bit more but getting sleepy, sleepy, sleepy...
Best regards,
Joseph