Scanner Antenna vs FM/Am Car stereo Antenna

[crownvic1]

I recently replaced my antenna for my Uniden BCT8 III Trucker Analog scanner with a Metra Roadworks Car Stero replacement cellular style mast. I was told that this would work for my scanner . But now my scanner only scans. I didn't want the long bulky style antenna. I belive by doing this i just made the scanner useless. Can only provide some insight?