"Ron Hardin" wrote in message
...

It's just a noise rush, but not white exactly. The giveaway is that
it's on
only one sideband of the station you're trying to hear. If you hear
it on the
LSB, the offending IBOC station is 10 kHz higher (not lower as you'd
expect);
and if on USB, then 10 kHz lower.


I'm not sure I understand. The spectrum plot shows two symmetrical
peaks off the carrier frequency. The noise I observed was consistant
with that.


So you need selectable sidebands to tell, or at least a BFO and notice
whether
the noise pitch goes up as you tune up (in which case the IBOC station
is higher)
or goes down (in which case the IBOC station is lower), starting from
the
interfered-with station.
--
Ron Hardin



I turned the BFO on, and scanned across the noise. I didn't think to try
to discriminate between a upper or lower sideband transmission. I was
trying to tell if there were multiple carriers in the sideband noise. I
don't think there was, but I wasn't checking it out very long. I played
with it for a couple of minutes, then I got on the computer to check if
there was an announcement of WGN was going IBOC. There wasn't, and by
the time I got back to the radio, everything was quiet. It's been quiet
since.

Frank Dresser