10 Meter Mobile

HTX-100 on the Jeep's dashI realized on October 12, 2013 that it had been eleven months since I had last made an HF contact of my own. I made some during Field Day 2013, but those weren’t really mine. There were several reasons why I couldn’t get on the air. I had lots of receive noise, little time, and an uncomfortable ham shack. I believe that I have solved these problems.

The noise that I was receiving was, by far, the worst inhibiting factor. My inverted vee dipole was picking up RF from the Ethernet wiring in my neighborhood and home. It was causing birdies every 25kHz on 10m. To add to that annoying S9 noise, powerline noise plagued me during most of the day. Turning on my Realistic 100HTX was a painful and disappointing task.

Since I moved to my new home, I was hoping all that would change. Boy, was I wrong. I attempted to mount my dipole in the attic, and it fit perfectly. The only problem: S9 noise across the entire 10m band! Even using a random wire antenna resulted in the noise. After a week or two of being frustrated by this, I decided to do a test.

I took the radio and the random wire antenna to the Jeep. I hooked up the radio to the power supply and inserted the random wire antenna. To my surprise, it was quiet. I heard a little birdie every once in a while, but it was hardly audible. I knew what I needed to do.

Gumdrop mounted to the luggage rack of the JeepI searched MFJ for a 10m vertical and a hitch mount. Since my birthday just went by, I had a little gift money left over. When it arrived I immediately did a quick install and ran 50 feet of LMR-400 to the radio in my garage. I fired it up to find a very quiet receiver. It was also midnight, and there were no stations to talk to either.

The next day I was able to make two contacts. It is not as easy to burn through pileups with 25 watts and a non-ideal vertical behind a large vehicle, but it sure beats the heck out of S9 interfering noise.

After testing that out, I routed coax through the Jeep. I placed my radio on the dash. I still had two problems. Having the antenna behind my vehicle still resulted in a good amount of noise. It is even worse with the engine running. After a little research I decided that there wasn’t a good enough ground plane under the antenna.

My Jeep Commander mobile stationIt was time to “ditch the hitch.” I took the gumdrop antenna connector off the hitch mount. I drilled a hole through the rear luggage rack and mounted the gumdrop antenna connector to the rack. I put the rack back on the Jeep and routed the coax. Wow! That made a world of difference.

Now I am able to make mobile contacts without a “hitch.” The only problem is that my Jeep is almost 11 feet tall. Drive through service will not be possible. My wife doesn’t really like it either, but she said, “well, if it works.” That means that it is what it is.

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