Possible yes, but results will probably not be what you expect. Go through this thread (
http://forums.radioreference.com/sp...57-running-one-scanner-multiple-antennas.html) - a 'sticky thread' that's all about this topic for details.
Two things to think about:
* First, to do it correctly, you'll need something to isolate the frequency ranges from the two antennas. A duplexer with one side that goes through 160 MHz or so and the other side that includes the 800 - 870 MHz range.
* Second, an easier (cheaper and less noticeable) option would be to get a single antenna designed to cover those two bands. The Larson tri-band 150/450/800 is a quality antenna that should do the job quite well. I have several and they work well for me. Since it uses the standard NMO mount, you can easily swap it in and out as desired (I swap between this and various single or dual band antennas as my needs/desires change (like using a shorty low profile antenna for garage access or a long, high gain antenna when traveling long distances).
