Last Modified: November 29, 2013
Contents: Basics; Doing it Right; Equipment Placement; Mounting Options; Avoidances; Antennas & Things; Odds & Ends;
If you don't take time to do the job right the first time, how are you going to find time to do it over?
Anyone planning on installing radio gear in their vehicles should read (at least) the Bonding, Noise ID, Antennas, Antenna Mounts, and Wiring articles. The latter is especially important if your vehicle is equipped with a Battery Monitoring Systems (BMS) and/or Voltage Quality Modules (VQM). It should be noted that BMS and VQM are acronyms used by Ford Motor Company, and other manufacturers may use different acronyms for these devices. They are a requirement of sorts to meet the fed-mandated Idle Engine Shutoff (EIS), also known by a variety of acronyms.
There seems to be a lot of misinformation about installing amateur radio in vehicles with respect to interference (RFI) of on-board electronics . Contrary to information found across the web, no automobile manufacturer prohibits the installation of radio gear, amateur or otherwise. Nor do any deny warranty claims on vehicles so equipped. In fact, they offer guides on proper wiring. Here at the ones for Ford, and GM, albeit a bit dated. The ARRL web site has information on other makes, here.
Very few amateurs go out searching for a new vehicle with the idea of mounting an antenna on it, or a transceiver in it. Typically, they already own a vehicle, and they decide to operate mobile. Either way, it always presents a problem in some fashion. Minivans, SUVs, RVs, Jeeps, station wagons, crossovers, and plastic-skinned vehicles present the greatest challenges. This generates a lot of emails asking for suggestions about mounting all-things mobile. This article is an attempt to answer those questions.
Whatever your stance on drilling holes, the performance you ultimately end up with is directly dependent on how much time and effort you're willing to expend. Or spend, as the case may be. Almost every mobile installation, there are things which could have been done better. In other words, what seemed like a wonderful idea up front, wasn't so good after the fact. This is of extra concern for those who have never done a mobile install before. Hopefully, the information presented here will minimize the amount of rework.
Speaking of doing it right, look at the photo on the left (click to enlarge). The owner, D. H. Gieskieng, K9CFE (sk), drilled several holes in the roof of his new vehicle to mount his version of a remotely-tuned antenna. Would you do this to your new vehicle?
The Photo Gallery's Other Installs album is a good resource for finding a spot to mount antennas, transceivers, and all manner of ancillary hardware. They are listed in alphabetical order by the call I received them from. In some cases, the calls have changed and/or the vehicle has been traded. If you're looking for a specific call, use the album's search function.
If you've been reading the other articles on this web site, you'd know this important antenna mounting point; It is the metal mass directly under the antenna, not what's along side, that counts! Typically, this requires drilling holes!
If you're really serious about doing a proper installation, here is a bit of sage advise: Purchase a repair manual for your specific make and model from the manufacturer! These manuals contain enough data to tear apart, and reassemble any or all parts of the vehicle. Typical prices hover around $75 to $125. After-market manuals (≈$25), like those sold by Haynes, always cover multiple models. As a result, coverage is generalized, and may actually leave out data you really need to do a competent installation. They're only advantage is their cheap price!
Doing it Right
The amount of work some amateurs will go, to avoid doing their installations correctly (as the left photo will attest to) is amazing! The HOS album of the Photo Gallery has many more examples. These installation faux pas go well beyond the mechanical, and include every facet of the installation, especially wiring (look closely on the left side of the photo at the dash board).
Another wiring faux pas is using an isolated battery charged by the vehicle's existing wiring. The usual (moot) excuse is that they couldn't find an easy way through the firewall. If you think this is your best solution, you're wrong! And think about this. A lot of amateurs receive flak from the spouses about their amateur radio extravagances. The main reason is simply because of the haphazard methodology they're so used to seeing in amateur-related venues around the house. Doing installations correctly is always a mitigating factor in reducing flak from a spouse.
Make everything as automatic as possible. This is one reason why automatic antenna controllers sell so well. Once setup, a single button push finds the correct antenna resonant point. No meters, no switches, just the existing Tune button on the radio. How much simpler can it get?
If you're planning to run an amplifier, now is the time to wire for it, not after you buy it. Remember, rework is always more costly in terms of time and money. The SGC and HL450B have automatic band selection built in—use it! If you use manual control, no matter how careful you are, sooner or later you're going to transmit into the wrong bandpass filter with predictable results. Better yet, with automatic band switching, all you really need to control the amplifier is a switch to turn it on/off, and an LED to tell you when it is on. Incidentally, the Ameritron ALS-500® does have automatic band switch option (ARI-500). Unfortunately, all of the cabling comes out the front of the unit, and it you need a remote on/off, you have to opt for the ALS-500RC as well (or add one to the ARI-500 yourself). Finding room for all of these devices is difficult in most vehicles.
Lastly, make sure you notify your insurance company and/or agent that you have installed radio gear in your vehicle. In some cases, the notification must be in writing. Most of the time, coverage riders are not necessary, but that is not a given. It is always best to check first, not after a loss. By the way, most automobile insurance companies will not cover radio equipment that is not permanently installed. This rules out mag mounts among other temporary mounting schemes.
If there is but one theme to follow when doing any mobile installation, it is Safety. Haphazard and improperly fused wiring, inconvenient transceiver mounting locations, or mounting too close to an SRS device are dangerous practices. Please! Take time to plan your installation, and execute the plan in a diligent manner. While none of us want to be involved in a vehicle crash, statistically one in seven will be at sometime in their lives. A minor knowledge of high school physics is all it takes to understand what damage an unsecured remote head or handheld can do during a crash.
The rule of thumb is, if it is loose, bolt it down! And, contrary to popular belief, there is always a place to properly screw down radios and/or remote heads. If you have to resort to Velcro®, double-sided sticky tape, suction cups, bungee cords, magnets (no matter how strong they are), wedged in blocks of wood, and rubber bands, you haven't studied the issue long enough!
Wherever you mount the your radio or remote head, it should be within easy reach, and easily viewable—not always an easy task to accomplish. Speaking of mounts, don't buy one, and then try to figure out how or where to mount it. That should be done first, and then a suitable mount selected based on the established criteria.
While some folks don't like to drill into plastic interior pieces, if you plan well they won't be easily visible once the radio is removed. The photo at left is a good example. The flexible goose neck is screwed down inside the cup holder. Once the rubber protector is replaced, the holes will not be visible. Note that the controls can be adjusted while resting the forearm on the top of the console. This is an ideal situation for obvious reasons.
Some mobile operators disregard the aforementioned, and continue to mount their transceivers within reach of the passenger side airbag. Their reasoning is often based on the fact that some airbags deploy from the center of the dash, rather than the top of the dash. They ignore the fact that airbags must meet fed guidelines with respect to coverage area. Don't be fooled! Any hardware mounted atop the dash to the right of the steering wheel, is within reach of the passenger airbag! Note the piece of the dashboard laying on top in the photo at right.
There are many places in the interior of a vehicle which should be avoided and/or where extra care should be exercised. One of those is under the seats. It is not uncommon for the side Supplemental Restraint System (SRS or airbags) impact sensors to be mounted within the seat(s) framework, and in some vehicles, the side impact airbags themselves. These devices are directly interfaced to their control system using secured connections. It is possible, albeit remote, to set off an airbag if these connections are mishandled. Disconnecting the vehicle's battery is not a workaround, as these systems have their own internal power source!
Further, cubby holes, center consoles, and storage boxes should not be used. Remember, modern transceivers rely on fans to stay cool, and thus require air flow all around them. This is one of the reasons factory-supplied mounting brackets should be used. In other words, don't place any transceiver directly on any surface.
Because it is tough finding room for all the requisite goodies, even microphone hooks. This leads some folks to use the foot wells to stash gear. If you have to resort to using the foot well, maybe you should ask yourself if that ancillary goodie is really needed.
Do yourself a favor, and resist the temptation to install hardware you really don't need. A good example is a SWR/wattmeter for an FM radio. By the time the meter tells you anything, you'll no doubt already know something is a miss. The only case for installing one on an HF transceiver, is for manually tuning a screwdriver antenna. Even then, the one in the transceiver should be adequate. The same goes for some amplifier remote controls. A good example of that is the one sold by SGC. Since the SG500 amplifier can automatically select the correct band filter, a simple remote control switch is all that's needed. It pays to remember the KISS principle!
There are exceptions, but even some of those can be avoided. For example; One unique feature of the IC-7000 is its video out. The video can be fed to a TVandNav2Go or similar converter, which displays the front panel on the Navi screen, hence no need for a separate video screen. It is considerably safer due to the Navi screen's near perfect mounting location.
If you own an IC-7000, and you don't have a Navi, then opt for a rearview mirror monitor. The unit shown at left is made by the AudioVox division, but others are available. Some models clip to the existing mirror, and may not be suitable for some vehicles. All current models are composite video in, and are compatible with the Icom IC-7000. Retail averages about $200, and some models come with a backup camera as well.
If you use an Icom IC-7000, here is something you should know. The head is easily knocked loose from the factory supplied mounting bracket. However, in the center of the bracket is a 1/4x20 threaded boss. Directly over that boss is a small trapezoidal indentation in the head. A short 1/4x20 bolt can be used to secure the head to the mounting bracket. If you use a longer bolt equipped with a jam nut, the head can also be mounted to a variety of brackets using the bolt as a mounting stud.
If there is one item you should have on board, it's an accurate voltmeter (in dash units aren't very accurate) like the two-wire Martel Electronics QM-100V shown at left. Its current draw is a scant 2 mils, so it need not be switched off.
As noted above, there is one mounting location that should never be used, and that is the top of the dash! Modern Supplemental Restraint Systems (SRS or airbags) virtually cover the whole top of the dashboard, and they literally explode in less than 200 milliseconds! That's about 200 mph! Obviously, any hardware within reach of an SRS (including the suction cup-mounted control head at right), will be flung far and wide when it goes off. As further proof of the dangers, here is a 2.7 MB wmv movie (used with permission of the NHTSA, National Highway Traffic Safety Administration) of an actual deployment. You need to play the movie several times to get the full effect. Note how many frames it takes for the air bag to explode to full size, and how far it reaches across the dashboard. Incidentally, passenger airbags always break the windshield above them, and often destroy the padded dashboard as well.
The mounts listed here, are not the ones shipped with your new transceiver. No matter who made the radio, the supplied (usually at extra cost) mounting brackets are rather brief. They're certainly not universal, but just a basic bracket which can be used to mount the remote head (if there is one), and/or the main body. As long as the mounting surface is flat, and you have lots of available space, they'll do just fine. We all know this is not the norm.
If you're a DIY (do it yourself) kind of guy, just about every decent hardware store carries DIY aluminum. All manner of rod and bar, flat and square, angled or what have you, is available. You can bend it, form it, drill it, and even tap it to suit just about any mounting situation. Unfortunately, not all of us have enough hand tools to fashion such a mounting bracket. Thankfully, adroit manufacturers have come to our rescue (I cover home brew later on).
There are a few companies who specialize in mobile mounts. Ram Mounts is one of them, and they have a very good selection aimed at us amateur radio operators. Their web sites offers a plethora of examples, including model-specific designs. The photo at left is just one of many.
Doug Johnson, W9IIX, has two different lines of mobile mounts, and enough accessories to go with them to mount just about any amateur transceiver. His e-mail address and telephone number are listed on his web site.
Gamber-Johnson, is most likely the largest manufacturer of mobile mounts in the world. Just about every police, fire, governmental, or allied safety organization uses them exclusively. While Ram Mounts' products (and most others) are universal, Gamber-Johnson's are designed for specific vehicles. Next time you see a parked police vehicle, look inside. The chances are you'll see a G-J mount.
Gamber-Johnson also make a first-rate, lockable slide mount replete with a coaxial QD good for up to 512 MHz. Cheap CB slide in mounts aren't much good above 50 MHz, and I don't know of any that are lockable.
In addition, Panavise, Havis, and Jotto Desk all make customized radio mounts for just about every vehicle you can name. Standard model prices vary from as little as $20, to as much as $200. Large custom mounts can run into the thousands.
If you don't drive off-road, a gooseneck mount might be in order. Several companies make them, and they attach via a seat mounting bolt. Checkout Panavise.
There is another aspect of mobile mounts every user should be aware of, and that is the attachment methodologies used. While I'll agree there are some spring clamp mounts, and some rare-earth magnet mounts that are very secure, the really safe method is to use a bolt! This applies to the actual mount, and to the device being held by the mount.
Tac-Comm specializes in what could be called portable mounts. They're unique as they can be stacked, although that is hard to see in the photo. A quick scan of their web site will show you a myriad of configurations. What struck me about them, they could easily be adapted for hump mounting. While few vehicles today have accessible humps, this is a decent alternative for those that do. The basic price of each module is $60, and there are top covers, front protection covers, and even carrying handles!
The modules themselves are expandable, with literally hundreds of mounting hole combinations. It is a niche product perhaps, but they're well made for whatever purpose you put them to.
Commercial mounts are not inexpensive. If low cost is an objective, the the next section is for you.
"If Velcro is so good, why don't automobile manufacturers use it? I think this mounting technique shows the loyalty of a car's owner, actually. It demonstrates a level of dedication towards the preservation of their cars to such an extent that they would rather risk injury or death, rather than drill any holes. My hat is off to them." Mark K5LXP, Albuquerque, NM.
A few things we use, can be safely attached with Velcro®. A microphone hanger comes to mind. Just remember, if you want it to stay put during a crash, it shouldn't weigh more than a couple of ounces. Even then, the more square inches of material, the better.
Some forms of the double-sided tapes are used by vehicle manufacturers to attach all matter of things together. However, the tape they use is made from industrial grade adhesives. Once they're stuck on, they stay stuck! If you know how much of your vehicle was put together using this stuff, you might be surprised. They even use "pin-cushion" fasteners to hold down trim pieces inside of vehicles. If you've ever looked inside a crashed vehicle, you'd know all of trim typically flies off. One could argue that it is designed to do that, but a four ounce piece of trim is one thing, and three pound remote head is another! The safest method is always one that uses screws, nuts, and bolts. If you need to have a removable radio, then invest in a slide mount.
Clearly, some mounting methods are far-less effective and secure than others. The essential element in any method you choose, is safety. If it is easy for you to remove (Velcro® for example), then a crash will remove it, no matter how secure you assume it is. For example, I was recent shown a very clean install of an IC-7000 in a Volvo S40. The head mount was properly attached by using existing screws in the lower dash. The problem was, the remote head was held onto the mount with a magnet, albeit one of those insanely powerful neodymium ones. The proud owner demonstrated how secure the head was by trying to pull it off. Well, all I did was slide the head sideways about and inch, and off it came! This just proves that some things look and sound good in theory, but are poor in practice. It pays to think safety!
The propensity of some amateurs to mount additional cooling fans blowing on their transceiver's heat sink, shows a lack of understanding about thermal dynamics. While it might make the owner warm, and fuzzy (pun intended), it is an inane practice. All transceiver manufacturers publish operating temperature guide lines for their various models. If you're exceeding the published limits, adding additional cooling isn't going to help much. Remember too, it is always best to mount transceivers where they can get an adequate flow of air all around the chassis. Part of this strategy is to mount the transceiver using the supplied mounting bracket, rather than flat against any surface especially carpeting!
Odds & Ends
There is one mounting location you don't want to use, and that is inside a bed-mounted storage box, no matter what it is, or how it is made. The reason is simply moisture condensation. Storage boxes are typically not vented since they're made to be weatherproof. In most areas where there are large variations in moisture and temperature extremes, condensation builds up inside the boxes with predictable results—rust in other words.
Bed boxes are often used as antenna mounts, although there are better solutions. If you do use a bed box, make sure they are properly bonded to the bed. If in doubt, run short (!) bonding straps to the bed on both sides of the box.
As a parting thought.... Neatness counts!