The even longer answer is UHF TV antennas come in many flavors but all in all they make excellent directional UHF scanner antennas when the elements are mounted vertically. I cut the "nose" off a combo antenna, drilled mounting holes in the back end of the boom, slapped it on a rotor and the first phrase that came to mind in my best fake Joisey accent (or maybe Bugs Bunny) was "geez, dis sucka woiks like dem Gangbustahs deah".
Oh don't forget the 300 ohm balanced impedance isn't something a scanner likes very much so just put an ordinary outdoor TV balun and some RG6-U quad shield coax on it. Like Captain Beefheart said; "Tasty lil' sucker!"