I previously had a business radio transciever in the 450.150 range in my pickup and it was hooked up to a thru the glass Larsen antenna. I have since taken out the radio as I changed jobs, and have hooked my BCD996XT Scanner to it. It seems to pick up local transmission in the 154.000 range and the 450.000 range but seems limited in the 700.000 to 850.000 range with the trunked systems. The mast is a straight whip mast about 12" tall. Is it possible to change the whip to something else that might work better as a all round antenna?
If it's an on glass antenna, you may have to contact Larsen to see if you can just "swap whips". There may be loading in the glass mount that wouldn't allow even the proper band whip to operate properly.
Went by the local Radio Shop today and had them change out the Larsen antenna. They said it would not work as well as the Radio Shack model 20-011 thru the glass antenna. Both are loaded for different bands. The install was quick and the Radio Shack multi band antenna seems to be working alot better than when it was hooked up to the Larsen.