Have Radio will Travel Part Two
Last time we talked travelling with your HT (handy talkie). This month I would like to cover a bit most of the mechanics of traveling with a radio.
Many hams have a mobile radio installed in their vehicle. If this is an interest to you, you need to consult someone who has a mobile rig already installed. This is more complicated than just plugging your rig into the cigarette lighter (read “accessory”) outlet. A mobile rig should be wired directly to the vehicle battery.
If you are considering using your HT as a mobile rig, it works fine for me, and it may meet your needs, too. I bought a Baofeng UV-5R radio specifically for my van. I run it off the battery inside the radio. You can also get a battery eliminator that will replace the battery and plugs into that accessory outlet that we just mentioned. Do keep in mind one thing- an HT will not usually put out more than a few watts. I have seen mobile rigs that put out as much as 100 watts. Its signal will go farther. I have found for the Metro Atlanta Area that four or five watts suits me. I have been in Lawrenceville and had full quieting while talking on the Atlanta Radio Club repeater downtown.
If you are thinking of just putting the whip antenna on your HT while driving around, forget it. It just won’t work. Why? Your vehicle acts as a giant screen, often called a Faraday Cage. The only signal that gets out will be through the windows.
Why not use the metal in your vehicle to your advantage? Put an antenna outside and use the vehicle as a counterpoise. (Remember that term from your technician studies?) Basically an antenna system consists of a radiator and a counterpoise. You might want to start by getting a magnetic (mag) mount antenna. These have a giant magnet at the bottom. Place it in the center of the vehicle and run the antenna wire through a convenient door. Be sure and get an antenna that has the frequency bands that your radio has. Most new techs get a 2 meter/440 radio. Make sure your antenna can do both bands. I purchased one as one of my first accessories. I never tuned it, but that might be a good idea for optimal performance. I didn’t had any test equipment at that time. I just connected it to the radio and it worked.
There are other types of vehicle antennas, but the mag mount is the easiest to install. The best thing with one of these is that if you sell your vehicle or need to move the antenna to another vehicle, it is a simple task.
Your antenna will have a PL-259 plug on it. Most HTs have a tiny “SMA” plug or a variation of it. You will need a cord to connect the radio to the antenna. Your best bet is to take the radio to the local ham radio dealer and have someone get the right connection for you. If you have an Elmer, he or she can help you.
If you are traveling locally, your radio likely is programmed for the local simplex and repeater frequencies. Going out of town, you will encounter different repeater set-ups. Also, in some instances, simplex frequencies may not be the same. There are at least a couple web sites that will have the information to program your radio for your destination. The ARRL sells a repeater book, and also has a traveler’s repeater guide on compact disc. I make a file on my computer with my HT’s software and entitle it with the destination city. If you are good at it, you might be able to program repeaters for an entire trip.
This column is not meant to be an all-inclusive guide for traveling with your two-way radio, but it will hopefully get you started.
Good luck!
73, David Harden, KJ4CMY