For those of us who use radio scanners, does anyone use an aftermarket antenna? More specifically, car antennas? Do they increase range enough to justify the expense?
I had a mobile antenna on my old pick-up truck. I bought it at Radio Shack; it was the sort of antenna that was applied to glass as seen below. It definitely helped pulling in distant transmissions and I didn't have to worry about fussing with a cable through my window and wind-whistle. I sold the truck long ago and never replaced it in my new truck. I got tired of having to disconnect it and reconnect the rubber duckie antenna every time I parked and ventured away for a photo. I see some magnetic mount scanner antennas that look really nice and would probably be a fine bet for good reception, but you'll have the cable-through-the-slightly-opened-window thing.
Danny Harmon on youtube had a video last year about his portable rig. the Diamond RH77CA antenna he mentions is a great compromise if you don't want an external whip on a magnet - I have several friends who have them on their handhelds.
I bought a different antenna for my hand helds, years ago. That was a big help. And I have used an external magnet mount 1/4 wave just like what he shows, for years and years now. It works. BTW- Mine has blown off. When I was passed by a semi rig going the opposite way. Whooom. The massive bubble of air he was pushing knocked it off! And it also scratched the paint..... Speaking of paint, I would suggest you find some sort of very thin material you can put between the magnet and your vehicle, as the magnet base can scratch your paint, when trying to remove it.
I carry three - the rubber duckie because of its ease of carry and durability, a flexible whip antenna perhaps 18" long and a longer telescoping antenna. The whip antenna offers some extra range, but its length gets annoying sometimes. The telescoping antenna gives excellent range, but I use it only when I'm waiting for a while in one place because its not flexible and has extra long length that makes carrying it difficult.
Back in the 1970's I was working a lot for an engineering company, out in the "fields'. Our hand held radios were Motorola, excellent. But they all had telescoping antennas. Even as careful as we could possibly be, we constantly bent and broke them.