Originally Posted by kc0wkp
If you are using the scanner at home you are going to find that you receive a much better signal with a base antenna than a mobile one.
Scanner Master, Ham City, and Radio Shack have some different options. There are also many other companies that have antennas depending on what you want to listen to.
Antennas for Police Scanner Radios
I am assuming you are trying to pick up the DeKalb Co. P-25 system. One thing to try would be using the tune option on your scanner to check the signal strength of the Control channels. If you get a good strong signal you should be good as far as antennas go but if not a good discone or other scanner antenna would be a good option.
To add on to this, I would say get a Yagi antenna if its just one tower site your trying to monitor, then you would need something to mount it outside to as high as you can, and get some good coax. I got 3 of CAY810 Yagis from this site CellAntenna: Yagi and Panel Directional Antennas
they work good I use them with LMR 400. I wouldnt go with a AntennaCraft/Radioshack discone they suck on 800mhz, in my expierence at least. If you can get a decent CC signal in Tune Mode, just not good enough you could go with the AntennaCraft ST2, witch in my expierence blows the Discone out of the water
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