This all started when I purchased a handheld scanner to listen to aircraft and HAM bands as I drove around and was out at the airport. The problem was with the "rubber ducky" antenna it came with - terrible range and signal strength. It seemed that if I was not literally on the airport grounds, it wouldn't pick up anything. OK, a simple answer - install an external mobile antenna...BUT not without it's own problems.
I drive a 1998 Ford Explorer. You would think, being an SUV class vehicle, that there would be several mounting options for an external antenna - WRONG! There are no "tubes" on the side mirrors to clamp onto, the lip on the rear hatch is bordered with a plastic molding so "trunk mounts" don't work, the luggage racks are attached with plastic so there is no chassis ground, and I didn't want to install one on the hood lip in front...and, of course, I didn't want to drill holes into the side or roof of the vehicle. There were basically two options left - use a magnet-base antenna or "get creative". Since a magnet base is not that secure and can scratch the paint, I choose the latter. And here is what I came up with:
Knowing the best place for an antenna is as high as it can be, as close to the center of the vehicle as possible - I started looking around and thinking. The luggage cross bars were out (plastic ends - no ground), but I noticed the slide-rails were metal, and the adjustable tie downs actually had metal attachments...which means they can be used to secure something, and will provide a chassis ground connection - important for antenna efficiency and to reduce noise. The gears were now turning! All I needed was a platform for the antenna. So, I cut out a mounting plate from some scrap 1/8" thick aluminum (no rust), marked the rail centerline, drilled two holes, and did a trial fit. It's important to note that the bolts used for attaching the plate are METRIC, not standard. (what a PITA!!) Any-hoo, it worked.
Now I could install any trunk or "lip" mount style antenna on the market - on the roof, and as close to center as possible. I can also do the same thing on the other side for another antenna - perhaps a CB or 2-meter HAM rig. What I choose was more than I really needed...today anyway...but it it has a neat feature I'll show you later. I bought a NMO (Motorola) style, fully adjustable, trunk lip antenna mount. It attaches to the mounting plate with allen screw clamps just like it would to a trunk lid. When mounted to the Explorer, I was able to adjust it to remove the slight angle caused by the curve of the roof - making the antenna perfectly vertical. I ran the thin coax around the front of the luggage rack, through the weather stripping, and down the door column into the cab. TA-DA!!! Mount finished!! For the antenna itself, I choose the MAXRAD MAXSCAN1000BS (black with spring) since the reviews were very good and it performed well in the aircraft band. Man, did THAT make ALL the difference with the reception. Now, where I would only receive signals from 1/2 mile, I get them at 10+. Well worth the trouble!
The special feature, you ask? Well, here it is - I can fold the antenna down and away when not in use or when I need additional height clearance. I've used this several times so far - mostly when entering parking garages.
Where did I get the mount? On-line from Universal Radio.