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The Amateur Amateur: Radiomobile

11/17/2008

If you've read my earlier columns, you know that I'm part of an ARES® team. And while I've yet to go on an emergency deployment, I've hauled my equipment to a lot of field exercises and demonstrations. I could just barely squeeze everything I needed into my old Prizm and still have room to get in it myself. Every drive was an adventure, with my equipment shifting this way and that. I was always afraid that a pole or something would surge forward and shatter my windshield. Or impale me.

Drive

So back around February I decided to get a vehicle large enough to comfortably carry my deployment gear. I figured I needed an SUV. Great timing, eh? Gasoline prices were in the stratosphere and SUVs are notorious fuel hogs. But I figured that if I got a really small SUV, I might just be able to feed it. I checked around and the Toyota RAV4 seemed to have a reasonable price and gas mileage. I was still uncertain, though, even as I entered the Toyota showroom.

The salesman, being well attuned to customers' moods, asked me what I needed.

"I need a regular car, but with a big...posterior," I said. "I want to throw a lot of ham radio equipment into the back of it."

"You want a RAV4," he replied.

Okay, so he could read minds.

I went ahead and bought a RAV4. It was the smallest SUV that Toyota makes. It wasn't exactly a highway hippo, more like a baby hippo. Thankfully, it fit in my garage. Parked next to my wife's Toyota Corolla, though, it looked like a M1 Abrahms Tank.

I will say right now that it does exactly what I wanted it to do, comfortably transport a lot of radio gear. Instead of trying to figure out how to get my equipment into my car, I now think about the best way to arrange everything to make loading and unloading easy. And if I have to abruptly hit the brakes, I no longer worry about being decapitated by a flying antenna mast.

You Might Think

The first thing I wanted to do when I got the RAV4 home, of course, was to install a transceiver in it. To me, an installation breaks down into three parts: Route the power cables, install the transceiver and control head and put in an antenna system.

There may be many aggravating moments during a mobile installation, but I find two parts to be particularly nerve-wracking. The first is finding a way through the firewall; the second is mounting the control head. They cause my knees to quake because they are the two points at which I may cause some damage to the vehicle.

Let's start with the firewall. Every mobile transceiver instruction manual tells you to connect your radio directly to the battery. Do not go through the cigarette lighter and do not go through the fuse panel. Well, that's fine, but how do you route the power cable from the battery into the cabin? Or perhaps to the trunk? The firewall seems like an impenetrable barrier.

I had been lucky with three previous installations. In each case I'd managed to find some sneaky little hole that led into the car's cabin. But after looking under the hood of the RAV4, I could find no such convenient passageway. I was stopped even before I had started.

Having no better plan, I got onto my computer and ran a Google search for some set of keywords like "firewall," "transceiver" and "RAV4." The search came up with precisely one hit. Incredibly, it was exactly the same question that I was asking: How do you route power cables through the firewall of a RAV4? And Robert Kozlarek, WA2SQQ, had the answer. There are rubber "boots" which guide wires into the cabin on both sides of the car. They are hidden behind metal struts and I would never have found them myself, so I am eternally grateful to Robert.

Tonight She Comes

I routed the power cables from the battery (yes, yes, I used fuses this time) to one of the boots, poked a hole in it, and ran the cables into the cabin. It was a new experience, not having to bend down (the RAV4 sits rather high) and having a lot of room under the hood. But after I had finished, I developed an unbelievable headache and vertigo. Do new cars have toxic fumes in the engine compartment? Is it a no-no to work under the hood of such a car for an hour?

There being no trunk, I simply placed the transceiver under the back seat. And rather than drilling holes in the dashboard (shudder!) or trying to install some special mount, I put a simple glue-on bracket called "The Bug" on top of the dash. The instructions said that the glue comes right off if heated with a hair dryer. I sincerely hope that's not an exaggeration.

Let the Good Times Roll

The last phase was to put in an antenna system. I knew right from the beginning that this would be a challenge. There was very little overhead clearance when I pulled the RAV4 into my garage. I considered bumper-mount antennas and glass-mount antennas, but what I really wanted was something on the roof. That meant that the antenna either had to be very tiny, or it had to fold over.

I looked at a lot of fold-over options. I came close to buying a motorized mount. I thought it would be cool to roll into my driveway, press a button and have the antenna slowly lower itself. But at the last minute, I decided that I could handle the arduous 5 second task of raising and lowering the antenna manually.

I wanted to install the Diamond mobile antenna that I'd had on my Geo Prizm. Just to keep the car's antenna equipment in the same family, I bought the Diamond K550KM fold-over luggage rack mount.

Installing the antenna mount was a bit of an arduous task. It's not that the instructions were complicated or anything like that. Due to inclement weather, I had to do the installation inside my garage. There just wasn't a lot of room in there for me to maneuver around my new oversized vehicle.

Magic

When all of the work was done everything fit and everything worked fine. I've taken my gear to several events this year and had no problems at all getting it all in and out of my SUV. And I'm already thinking about installing additional transceivers in the SUV. There's plenty of room inside and the power is already routed.

But additional antennas? That's going to take some more thinking.

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 are invited to contact the author via e-mail.

 

Gary Hoffman, KB0H
Contributing Editor



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