The Amateur Amateur: Going Mobile

By Gary Hoffman, KB0H
Contributing Editor
August 15, 2001

I traded in my old car and got a newer one. My old car was bright red and had lots of antennas. My neighbors probably thought that I was the fire chief. I was fond of my old car; it was my Amateur Radio training ground. I learned more about radio from that car than from any other source. Cars don't live forever, though, so I had to get a new one.

My new car was wonderful to drive, but it had one glaring omission: It had no ham radio. I'd saved the dualband ham radio from my old car, but I knew that installing it would be a daunting task. Step 1 was to get power from somewhere. The mobile radio's instructions were very specific:

• Do not plug your transceiver into the cigarette lighter.
• Do not connect your transceiver to your vehicle's fuse box.
• Do not tap into any of your vehicle's power cables.
• Do not pass GO; do not collect $200.

The control head prior to the installation of the "variable-tension multi-strand filament immobilizers".

The instructions only approved of one power source--a direct connection to the car's battery. That meant the power cable would have to go through the car's firewall. I had visions of drilling and destroying something vital, severing the brake line, rupturing the fuel line. I suppressed a shudder. There was no way that I was going to do it myself. I needed professional help.

I'd been down this road before. I'd found a friendly mechanic to route the power cables on my old car, but he had moved. I looked around for a new mechanic, but kept finding only unfriendly ones. Basically, if the mechanic could not find a code for the job in his computer, then he wasn't going to do it. I eventually found a mechanic who was willing to route the power cable for me for a simple labor fee (he had no computer).

The mechanic was somewhat hygienically challenged, but he did an excellent job. He ran power cables to both the passenger compartment and the trunk. Without being asked, he also put ring terminals on the engine compartment end of the cables, making it easier to connect them to the battery. He earned a warm place in my heart.

My mobile unit had a removable front end, or "control head." That's where all the knobs, buttons, and "fiddley" things were. Control heads are for those of us who live in big cities. We hide the radio in the trunk and leave only a snap-on control head in the passenger compartment. Mounting the radio in the trunk was easy, since it was dark back there, and no one would notice the big, ugly drill holes I'd made.

Inside the trunk: a spaghetti mid-Western.

Okay, the radio was mounted. All I had to do was to connect the power cable and go get a beer, right? Not quite. The fun had just begun.

Remember the control head? I needed to mount it in the passenger compartment. Otherwise, I'd have to operate out of the trunk.

I found a route for the control cable, and with only a few skinned knuckles managed to run it from the trunk to the dashboard. I connected the cable at both ends with teeny-tiny screws. I worked very slowly and very carefully and used a magnetic screwdriver. This time the microscopic screws did not escape and fall into inaccessible crevices. (As I said, I'd done this before.)

I then spent an hour staring at the dashboard trying to figure out which part of it I was willing to mutilate. My options were limited. I had to be able to reach the control head, but I couldn't put it where it would be in the way or covering up something essential--like the heating/air conditioning vents, fuel gauge, clock or CD player.

That left approximately zero places.

I am good with jig-saw puzzles, however, so I eventually found a spot for it. Hands trembling, I drilled a couple of holes in the dashboard and mounted the control head.

Finished? Hardly. The speakers were next. My radio operated on two bands and had separate speakers for each. In my old car, these had been mounted on the rear deck. It had taken a lot of effort to install them, and I'd made nasty holes during the process. I didn't want to repeat that mistake.

There weren't many spaces on the rear deck of my new car, though, and looking at the underside of the deck, not many places where I could run bolts. Three curious hook-like objects occupied the best spots. Even more curious, each of those strange hooks sat right over a bolt. I checked the owner's manual to see what they might be. Aha! They were hooks, indeed, and designed to secure a child's safety seat in place. Perfect! I had no children, so I could safely remove the hooks and replace them with speakers!

Well, that didn't work. I could not loosen the nuts and bolts securing the hooks. I should have remembered Gary's First Law, which states "It takes a special tool." I suspect that in this case the special tool must be an atomic wrench. Eventually I used Velcro to secure the speakers. (Don't laugh, it worked!)

The next item on the checklist was to plug in an antenna, which was no big deal. The radio was in the trunk, and I was using a magnetic-mount antenna on the trunk lid. Very convenient. The most difficult part of that operation was deciding where to stash the excess coaxial cable.

Your columnist in the trunk--but can he get out if the lid slams shut?

I connected the power cable to the radio. I spent a lot of time wrapping up all of the cables (there seemed to be a lot of them) and finding places to tie them. This was, after all, the trunk. A lot of junk would eventually find its way in there, and I didn't want any of it to snag a loose wire and rip it out of the radio. Last of all, I opened the hood and connected the power cable to the battery.

I climbed into the passenger compartment and admired my work. I pressed the ON button, and voila! My radio came to life!

One cosmetic detail remained. The control head cable was flopping around loose and occasionally got in the way. My wife Nancy provided a couple of variable-tension multi-strand filament immobilizers,^* and I used them to secure the cable to the dashboard.

And how well did the radio work? Well, that's a story for another time.

*bobby pins

Editor's note: ARRL member Gary Hoffman, KB0H, lives in Florissant, Missouri. He's been a ham since 1995. Hoffman says his column's name--"The Amateur Amateur"--suggests the explorations of a rank amateur, not those of an experienced or knowledgeable ham. His wife, Nancy, is N0NJ. Hoffman has a ham-related Web page. Readers may contact the author via e-mail at [email protected].

© 2001 American Radio Relay League