In Part #1 of this series I covered the mission of this Ham-In-The-Box project, requirements and limitations, and the initial challenges that I faced. I also outlined each piece of equipment that would make up the final product. In this article I will cover a step-by-step build process along with tips that I discovered along the way.
Just a reminder of the mission of this project –
To be able to rapidly field deploy a Ham radio, for which I am licensed to use, in the event of any emergency while maintaining a secure and protective storage environment.
Step 1 –
I quickly realized how inconvenient working on the box would be with the box lid in place. So the first thing I did was take the lid off. To take the lid off get a punch and tap the hinge rod out from the inside out. Once you have about 1/2” of the rod exposed then grasp the rod with a pair of vice grips and pull it the rest of the way out of the hinge.
Next, I laid out the components to ensure they would all fit and be accessible as needed. The PWRgate warned about heat being generated by the unit so I decided to install it off to one side where I could install a cooling fan to blow air directly onto its heat sink. I had to implement a “remote head” installation of the Yaesu FT-8900R due to its overall size. If I didn’t the head would be too close to the lid when closed and I didn’t want to take the chance to damage it. It worked out great since it looks like a much cleaner install. I also took care to install the radio as far away from the heat generating PWRgate to avoid over heating the radio.
Step – 2
I laid out the first level of structural material (framing). I cut the upright 1-1/4” angle iron (aluminum) to fit very snugly into the box. The corners of the aluminum actually bite into the plastic. Once I had the uprights cut to length and placed in the box I then placed the lower cross-member into position based on securing the AC power supply that would be placed at the “bottom” of the unit when the box was placed on its side during operation. That was due to the power supply’s weight; it was the heaviest item that would go into the box.
Next came placing the radio. I based the top cross-member’s position based on the radio unit’s size; I wanted the radio to be up and out of the way. I also wanted the rear of the radio to facing outward for access to the power cable, data port and antenna coupling. That positioning also allows for the fan to move the unit’s heated air to the outside of the box.
Here was an issue I ran into; the radio attaches to the mounting bracket with screws that come from the sides of the radio into the bracket. With the bracket mounted to the cross-member I can’t access the screws to remove the radio from the mounting bracket. So I used the regular screws to mount the radio to the bracket but I used #8 bolts with wing-nut/star-washer to install the mounting bracket to the cross-member. To remove the radio unit you remove the wingnuts and then remove the mounting bracket with the radio attached.
Step 3 –
To mount the PWRgate I used a short piece of 1-1/4” angle aluminum to mount the PWRgate to. I used #8 bolts with wingnuts and washers. I had already marked and drilled holes to match mounting the PWRgate mounting bracket to the cross-member. If I have to remove the PWRgate unit it won’t be easy. The left-hand wingnut it tough to reach with my big hands and fingers but it can be done. Trying to remove the bolts and nuts from the units mounting bracket would have been impossible since the unit itself prevents access to the bolts/nuts mounting the bracket to the cross-member.
Now it was time to get the AC power supply placed and secured. But as I was looking at that part of the build I was thinking this might be the time I could combine the structural parts. So I measured and placed a lower cross-member and put it in-place to secure the AC power supply. As I did so I realized that could use that same cross-member and the other lower cross-member as the “base” to install the battery booster too. But I had to space the cross-members to match the width of the booster’s base and mounting holes. A little giggling around and I got it all lined up. Then came the challenge to secure the AC power supply to make sure it wouldn’t move around. But, there was a problem that the height of the AC power supply was just a little too tall for the front cross-member. Solution – cut a small notch in the front cross-member to offset the height issue. The side-benefit to doing so was a very secure mount for the AC power supply. All that being said I did cut a small mounting bracket to mount the AC power supply to both the front and rear lower cross-members. That added extra stability to the overall lower structure. Notice I had to cut out some area of the mounting bracket to keep the AC power supply’s cooling vents free of obstructions.
When I was working at properly placing the battery booster I had to ensure that I could mount a “T” on the antenna connection (SO-239) on the rear of the unit. The “remote” outlet is back there as well but I don’t intend on using that option. I did have to ensure that I could see the booster unit’s LED lights and have access to the button on the front panel of the unit. I also had to give consideration to connections on the top of the unit. All-in-all the placement was near-perfect.
Step 5 –
I felt that the front lower cross member was still not stable enough and could move around too much. I also wanted to start putting in the pieces that would integrate the front panel frame into the rest of the structure. I decided the best way to do that was to run a piece of 1-1/4” angle between the front and rear lower cross-members that would run vertical to tie into the front panel frame.
I used 2 rivets to secure the lower part of the vertical support to the lower rear cross-member. But for the front lower cross-member I used a #8 bolt with wingnut and washer to allow the removal of the front lower cross-member that would help me if I had to move the AC power supply.
Also, I pre-drilled the hole that I would use to secure the vertical to the front panel frame. To connect the two I used a #8 bolt with wingnut and washer. This would allow me to remove the front panel frame if needed.
Step 6 –
So now it was time to start actually installing the different components to the structural frame. I started with securing the PWRgate and then the AC power supply. Prior to installing the AC power supply I installed the fused pig-tail to the power supply and making the connection to the PWRgate.
Step 7 –
I placed a 90° SO-239 connector on the radio antenna to reduce the radical bend in the antenna lead that would connect the radio to the battery booster. Remember the battery booster has a RF sampling port that enables the booster to only boost the battery when the radio is actually transmitting. Receiving doesn’t require or need any boost in battery power.
I also had to make a custom remote head extension cable. It is a 6-wire cable with an RJ connector. I could have bought a cable but making the right length on the spot was easier and cheaper. The cable has to reach from the rear of the radio unit to the remote head.
Step 8 –
One of the easiest parts of this build was installing the remote head mounting bracket. I wanted it fairly low in relationship to my eyes & head. Looking slightly down at a small display screen and buttons is much preferred to looking straight ahead or elevated. I used two self-tapping, self-drilling sheet metal screws with hex heads.
I was going to complete my “build” post today but while diagramming my wire layout I found a flaw and had to do a little re-engineering. Not to worry though, it is coming along just fine, a minor tweak is all. So I will post this part of the build, finish up with Part #3 being the front panel, the wiring, and the antenna.
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