A Mobile Mount for Radio Control Heads

Matt Roberts - matt-at-kk5jy-dot-net

Published: 2016-12-17

One of my favorite radio activities is mobile operation.  I don't tend to talk while I drive, but I do like to listen in on HF activity when I am out on a long trip.  I have also been known to enter Field Day as a 1C station from time to time, while parked in some summer shade.  One of the biggest challenges to mobile HF radio is mounting the radio--and more importantly, its remote display and controls--in an effective location.  Every year, new cars come out, and the automobile maufacturers leave less and less driver-facing space unused.  The cars I drove in my teenage years had room for huge Motorola control heads, stacked on top of each other.  Today, I find it hard to place a single tiny FT-857D control head anywhere in reach of the driver's seat.

One thing new cars seem to have in abundance is cup holders.  Since cup holders get used for beverages and everything else, it seems modern trim designs have at least two such locations for front-seat passengers, and sometimes for the back-seat passengers, too.  So rather than wasting this space for something as useless as a cell phone, I set out to find a solution that would exploit my vehicles' cup holders as an effective mobile mount.

Something to remember about the humble cup holder in a modern car -- they excel at their intended purpose.  Beverage containers come in all manner of shapes and sizes, and a well designed cup holder will accept any sane shape of beverage container, and keep it very secure during all manner of big-city traffic maneuvers.  The reason for this is probably more than user convenience.  People tend to spend their groggy commute time in the company of hot coffee or tea, and the last thing you need is for your car to dump hot liquid all over you while you try to drive.  My plan was to exploit this design property to devise a mobile mount that would hold my radio's control head just as steady while on the road.

Amazingly, there aren't many prefab products available for using a cup holder for a mobile radio head.  For that matter, there aren't many good mounts for radios, period.  I have tried several different options, but they are all too flexible and/or cheap to be used reliably to hold a control head in place, and some are just inconvenient to use.  Since I couldn't find what I wanted online, I set out to build one.

Protype Mount Protype Mount
Figure 1: The Prototype with TS-480 Controller

The Prototype

The first mobile mount started life as a plastic cup from Eskimo Joe's, a local burger joint (who, incidentally, sells T-shirts to the entire world).  I used rather thick tie wraps to secure the base of a TS-480 control head to the cup, through some holes drilled in the cup.  Once the ties were snug, the mount was an instant success, as shown in Figure 1.  The console shown is in a 2012 Toyota Camry (a poor excuse for a car if there ever was one).  The parts for the mount were nearly free, with the evening soda order being $1.99 or so.  The mount placed the control head where it was easy to see, easy to control, and most importantly, it made the control head absolutely immovable while the car was in motion.  The radio head didn't block any vehicle controls or displays, so it was a good fit.  I also used this mount in a 2005 Chevrolet truck, where it was again an excellent fit.

The prototype mount worked well because the TS-480 has a stand that can be easily tied to the plastic cup.  The stand was meant to be used at a desk, but since the stand's base is substantially larger than the rim of the cup, the stand also works well when tied down to the cup used as a "surface."

Plan B

After using the mount in Figure 1 successfully for some time, I picked up an IC-7100 to use in the truck, to replace the combination TS-480 and FT-8800 with a single radio.  The new radio also has a remote control head, but it does not have the kind of stand that the TS-480 has.  On the IC-7100, the bottom of the control head is the stand.  So a new mount was needed to allow me to use the new radio the same way as the old one.

Protype Mount Protype Mount
Protype Mount Protype Mount Protype Mount
Figure 2: Second Prototype with IC-7100 Controller

The IC-7100 is apparently intended to be mounted via a 1/4" bolt on its base, much in the same way that a camera is attached to a tripod.  This seemed like a solid way to attach the radio to the car.  On a recent shopping trip, I found a cheap foam insulating mug that is meant to hold a cold beverage can.  Apparently these aren't all that popular, because the item was on clearance, but it served as the main ingredient to the next version of my mobile mount.

After some tinkering, I found that an inverted aluminum can served as an excellent replacement surface that fit perfectly into the foam mug.  To this, I attached a 1/4" fastener, to which to attach the radio.  To further strengthen the end of the can, I attached a metal plate to the stud, and pulled it snug to the bottom of the can, which is the top of the mount.  The finished product can be seen in Figure 2.

The fastener used is a 1/4"x1.25" bolt, and the washers are 1" fender washers.  I used stainless steel because I like it, but zinc-coated hardware of this size is also commonly available at hardware stores.  The stud turned out to have just over 1/8" of extra thread after the radio is attached.  Extra washers can be added between the radio and the stud to provide extra support if desired.  I also used split washers on both nuts to prevent the hardware from working loose after repeated assembly cycles.

The only "critical" dimension is between the plate and the bottom nut on the can.  The plate should be flush with the rim of the can, and the top edge of the nut underneath should be almost flush with the plate." This allows the nut on top of the plate to pull the plate flush with the nut underneath, to obtain a snug fit, but without distorting the curved part of the can so much that it crushes it.

The blue and white mug is made from a relatively firm foam material, that would be excellent for smaller cup holders, where a little squeeze is needed to get it to fit snugly.  The hard plastic from the first prototype is better for cup holders that already have some kind of soft insert material installed.  The cups are a common give-away you get with dinner at places like Eskimo Joe's or Rib Crib, but amazingly they can be purchased online, as well. :-)

Mix and Match

I combined these approaches to make a third mount, which has the 1/4" stud for the IC-7100, but also uses the rigid plastic cup, which is shorter and wider than the foam mug.  That mount is shown in Figure 3.  As you can see, there are all manner of ways to fit a mobile radio controller to a cup holder.  Most mobile controllers will include hardware for mounting at an angle to a flat surface, which means that a metal plate attached to a cup is really the only additional hardware needed.

The metal plates I used were the bottom metal cover from old project boxes from Radio Shack.  These are the kind of black plastic boxes that are sold for hobbyist projects, and each box comes with two bottom covers, one that is plastic and one that is metalic.  I always used the plastic ones, because they look better, so I have a small pile of aluminum plates in my scrap collection.  There are plenty of other sources of such material.  The local steel and welding supply shop might even give you scraps that are large enough to cut into a similar size.  Remember to remove sharp edges with a file if you cut your own plates.

Protype Mount Protype Mount
Figure 3: Third Prototype, for IC-7100

A nice feature of this approach is that it can provide a solid mount, as one would expect from a more permanent installation in the vehicle, but it is completely and easily removable, when needed.  So when I want to move the radio to a new car, or if I just don't want the radio in the front seat with me today, I can lift it out of the cup holder, spin the mug off the control head, disconnect the wire, and voila!  Installing it again is equally simple.

The cost is hard to beat, too.  The component cost for all prototypes was less than $3, combined.  And the utility is far better than any commercially available product I considered.  The attractiveness of the installation depends on the selection of materials. :-)  A local ham suggested that I fill the cup or can with plaster, or other similar material, in order to add rigidity to the container, and to move the center of mass down a bit.  He has better mechanical skills than I do, so I may try his suggestion if I can find an appropriate material locally.

Note that the safety of mobile installations is of paramount importance.  K0BG devoted an entire section of his excellent mobile radio website to installation safety, and another section to operational safety.  It is worth a read over that information as an introduction to the safety issues associated with mobile operation.


As with all open source technical information, if you attempt to use any information contained above, you do so at your own risk, and you are entirely responsible for the safety of your installation and its operation.

Copyright (C) 2016 by Matt Roberts, All Rights Reserved.