Would an antenna like the Diamond CR8900A (quad band 10m, 6m, 2m, and 70cm) work with a CB as well? I would prefer to run the antenna to both my yaesu ft8900 and my CB with both receiving at the same time. Only one would be transmitting as I cant drive a stick and talk on two radios at once... yet.
Just want to make sure I can get away with only one hole in the roof.
For receive purposes it could work (but I personally would not do it), but not for transmit. The CR8900A is a very narrow banded antenna when you get right down to it, as are many multiband antennas. The 2:1 VSWR curve will not allow the FM portion of 10M (centered on 29.6 MHz) and 11M (centered about 27.2 MHz) to both have a good SWR. One or the other might be possible, but even then I am not sure you could retune the CR8900 to give you 11M and still keep the other bands happy.
For what it is worth the Diamond manual only specifies the 1.5:1 SWR curve, and that is 200 kHz wide. Assuming the 2:1 curve was twice that wide (and that is very unlikely) you would still only have 400 kHz of usable transmit bandwidth. And, FM 10M is about 2400 kHz from the center of 11M.
The other question is how are you going to hook both radios to the single antenna? I do not know anyone who makes a duplexer with a cutoff between 11M and 10M.
T!
