A Mobile Mount for Radio Control Heads
Matt Roberts - matt-at-kk5jy-dot-net
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
Figure 1: The Prototype with TS-480 Controller
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."
After using the mount in Figure 1 successfully for some time, I picked up an
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.
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.
Figure 2: Second Prototype with IC-7100 Controller
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
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
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
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.
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.
Figure 3: Third Prototype, for IC-7100
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.