Dale Parfitt wrote:

Only problems with a BP filter (aside from its gradual skirts,
unless it has 5 poles or more) is you will have to disconnect
it to listen to other freqs and its attenuation on the likely
culprit, FM broadcast, will be minimal.

The scanners are dedicated to airband (providing feeds to LiveATC.net)
so removing the filter isn't an issue. I installed an AOR ABF-125
filter tonight, and the overload problem seems to have been solved. I'm
still not overwhelmed with the quality compared to what I get from my
airband transceiver, but that's $300 vs. $100, I guess. I might try the
FM notch filter, too, and see if that makes things any better, but for
now, at least I'm up an running. Thanks to everyone for their help /
suggestions...