Awesome MicroMobile® MXT275 Install How-To
Hello JL Forums gang. My build continues. In this thread I'm installing a Midland MXT275 radio and MXTA25 ghost antenna.
The first challenge was where to put the antenna. I reached out to Midland to ask about a few locations (I was thinking about the mirror and the hood) and the pluses and minuses of each...here is their reply:
Compromises are the norm when choosing and mounting an antenna, but I'll just list some general points that improve performance. I doubt that mirror mounting location will give acceptable performance.
1. The best place to mount an antenna is in the center of the highest metal surface on the vehicle, often the roof. If the metal surface is the hood, center mounting is not practical, and one side of the cowl is generally used.
2. All our antennas perform better when mounted on a ground plane, meaning a metal surface beneath the antenna. The larger the surface the better, but a minimum of 1/4 wavelength radius (about 6" radius at 462 MHz) is a general rule.
3. Using a permanent mount will normally give better performance than a magnetic mount.
4. If using a mount like the MXTA24, the antenna will perform better if the saddle washer contacts with metal that is also bonded with the vehicle chassis and transceiver ground.
5. Mounting the antenna next to a vertical metal surface will shield it from radio signals, and block the radiation pattern, from that direction. Plastic, fiberglass and glass surfaces will also block the signal to some extent, they but not as much as metal surfaces.
6. Consideration should always be given to maintaining the minimum separation distance from the antenna to humans, when choosing the mounting location and before transmitting. This distance is listed in the owner's manual RF exposure statement, 2-3 ft for the MXT line.
Using these guidelines, I chose the hood as my place to mount the antenna...I have no intention of dropping the windshield so out came the drill bits and cut off wheel...
This location gave the least amount of compromise and good distance from me and my passenger. Also, I liked the location because it is different than others I've seen. Being a little different is ok.
I crudely hacked a couple holes in the inner structure of the hood in order to run the antenna inside the hood. No real reason other than I wanted to hide it. I do plan to clean up the holes this winter, making them look less...shitty.
I used some vacuum hose to protect the cable where it exited the hood structure.
Rather than fight with existing grommets in the engine bay, I removed the cowl and ran the cable through the seal where the windshield frame meets the tub. I secured the cable with zip ties in a few places to keep chaffing from vibrations to a minimum.
After getting the cable into the cab, I ran down the side of the dash and tucked it behind the trim.
I then ran it under the scuff plate and coiled the extra cable under the rear floor vent.
For power I tapped into the front cigarette lighter power with a tap and bundled the junction up and stuffed it all back into the dash.
I ran the antenna cable and power through the center console so I could mount the the radio on the back of the console. Everything is still able to be disconnected incase I need to remove the radio.
I am incredibly happy with the range and performance of the radio thus far and will report more on its performance as I get more hours on it.