Battery Boxes

I built a battery box out of a case from Harbor Freight. I had seen a similar box sold by Powerwerx for $259.99. Given the availability of these boxes at a much lower price ($34.99) and the cost of the parts involved ($140.78, with a bigger battery), I thought I’d be better off building a box at a reduced cost (~$176). I would also have the advantage of adding more PowerPole connectors instead of a cigarette lighter socket. If I ever need to plug into such a socket, I have a PowerPole to cigarette lighter socket adaptor that I made from spare parts.

While I did not compute labor costs in the box construction, I included all the parts (except the wiring, which I had lying around the shack). I find building little things like this relaxing. So, the labor costs aren’t really an issue for me. I didn’t even time how long it took me. If you find this laborious, You may want to just buy a box from Powerwerx.

Box Construction

To build this box, I had to drill 3 holes in the side that were big enough for the panel mounts. The three panel mounts I decided to include were a combination USB A/USB C/Voltmeter, and two mounts that house two PowerPole connections each for a total of 4 PowerPole connections.

I figured I could run a radio, an antenna tuner, and a light, which would use up three PowerPole plugs. I could use the fourth plug to simultaneously charge the battery if I’m somewhere with access to electricity or if I want to use a portable solar panel.

To drill these holes, I found that a stepped drill bit helped me select the right-sized hole for the size of the panel mounts. While not all panel mounts require the same size hole, they’re similar. This bit will help you step your way toward the right size so that the threads fit through but not the collar of the panel mount.

Once the holes are drilled, take the nut off the panel mount, slide the mount through the hole, and tighten the nut back on the panel mount until the collar of the panel mount is secure against the side of the box.


Wiring is fairly simple. The USB charger comes with its own wire that has a ring on one end for the battery terminal and clips that fit into the back of the panel mount. It’s important to make sure that you get the polarity correct. A ‘+’ for positive (the red wire) and a ‘-‘ for negative (the black wire) is etched in the plastic. If you have trouble seeing them, a flashlight from a cellphone helps a lot.

When it comes to the PowerPoles, you have to be a little more attentive.

Make sure you use the right gauge of wire for the power you want to pull. I probably overdid it with 10 AWG wires, which kept me from putting multiple wires in a ring connector. With four think ring connectors, I barely got the battery screws to hold them down. However, I wanted to be able to pull enough amps to run my 100W radio and didn’t want to worry about which PowerPoles could handle which current. Having the 10 AWG wires on all of them makes that possible.

It is a best practice to use red for positive and black for negative. Doing so will make it less likely that you will attach the wires to the battery incorrectly.

Make sure that the wires are long enough to reach from the battery terminals to the PowerPoles. Put the rings on one wire end and PowerPole inserts on the other. Place the inserts into the PowerPole housings. Then, attach the rings to the terminals of the battery. Red to the positive screw and black to the negative screw.

Preventing Rattling

Once this is done, you’ll want to secure the battery. This step will keep the battery from rattling around when carrying the box by its handle. Fortunately, the box came with a bunch of foam rubber that can easily be separated to match the shape of whatever is being stored in the box. Carefully tear the rubber (along the perforations) to match the large area between the battery and the panel mounts. Then, use the scraps to fill in the area between the battery and the front of the case.

Testing the Battery

At this point, you’re ready to test the battery.

A button on the USB panel turns on the connectors and the voltmeter. Press the button and verify that the battery is charged. The full charge will be somewhere around 13.8V. If the voltmeter doesn’t show anything, the wiring polarity is likely incorrect. The battery probably needs to be charged (see below) if the voltage is too low.

Plug a USB cable into each port and verify that it charges your phone. This is probably what you’ll use it for. In my case, I use it to power a Raspberry Pi. If you want to do this, you’ll need a USB C port labeled PD.

Once the USB system works correctly, check the polarity of the PowerPole ports with a voltmeter. If the voltage is negative with the red lead connected to the red side and the black lead connected to the black side, you’ve wired it backward. If they are all positive, plug a device into each port and verify it has power. If so, you’re good to go.

Charging the Battery

To charge the battery, simply hook a charger to one of the PowerPole ports. I use NOCO chargers. I take the adaptor that comes with the charger and convert it PowerPoles to make this easier. For a battery this size, I use the 1 amp model. Be sure to set the charger’s battery type to the type of battery you put in the box. I use LiFePO4 batteries, so I set the charger to 12V Lithium.

Parts List

Here are the parts other than wires and connectors that I purchased to build this box.

Making an Emergency Power Lamp

A lot of people have lanterns, Flashlights, and candles for lighting when a power outage occurs. I’ve started building my lamps into my radio power supply so that they’re independent of power mains. In essence, my shack works the same way whether the power is out or not. In this article, I’ll go through my solution and touch on the drawbacks that I was trying to avoid.

The first drawback was battery power lost in converting DC to AC. I could just run a normal lamp plugged into an inverter that is attached to my LiFePO battery bank. This wastes power that is lost in the conversion from DC coming out of the batteries to AC going into the lamp. In order to avoid this loss, I want to keep the entire system on DC power.

The second drawback is the form factor. I want normal lighting without figuring out where to place the lantern or how to hold the flashlight correctly. Lamps are nice because they’re positioned for optimal lighting and can stay there.

To address both of these concerns, I found some 12 volt DC-powered light bulbs. I can put them in the lamp and run the lamp on my battery. I could accomplish this with a simple lamp plug to power poles converter, which would run totally on DC, but would also let me use the lamp with AC power and an AC bulb. However, this raises more concerns.

The third concern is that an AC bulb should not be plugged into DC and a DC bulb should never be plugged into AC. While it is unlikely that I would make this mistake, someone else in my household that doesn’t understand how this system works might make this mistake.

To add a bit of Poka-yoke (mistake proofing) to my solution, I cut off the plug. This ensures that the lamp will never be plugged into AC again. I put power poles on the wire coming out of the lamp. It is important to get the polarity right when wiring this up. When the light manufacturers make the light, they don’t have a standard for which wire goes to the lightbulb case and which goes to the lightbulb tip. You can find this out by using a multimeter to test the continuity between each of the wires and the center connector in the socket. Whichever wire goes to the center connector, that’s your red power pole, the other is your black power pole. If neither of them connects to it, you most likely have the lamp switch in the off position.

The fourth concern is that lamps are not as simple as they used to be. When selecting a lamp be sure to pick one that is just a lamp. If you select one with a USB charger or AC outlet built-in, your conversion from AC to DC would also be sending DC to these circuits, which could have undesirable outcomes ranging from higher current draw to fire. Be sure to select a simple lamp that doesn’t have other features that rely on the AC input. I chose a desk lamp so that I’d always have lighting for my radio desk.

All that’s left to do is to plug it into a battery supply. Obviously, that supply has to have power poles coming out of it in order to plug into it. I have my batteries going into a power pole distribution box, into which I plug in my lamps. I’ll have another blog entry detailing the battery box that I’ve constructed to make the light portable enough to be moved around the house.

My UHF/VHF Setup on the Island

I was on a simplex net tonight on Bainbridge Island. I was explaining what equipment I have and promised to email the net members with more details.

Once I wrote it, I thought it might be nice to post here.

My 25W base station radio is the Leixen VV-898E. I don’t like it because it doesn’t work with Chirp. The lower power VV-898 works with Chirp. It frustrates me to no end that one works where the other doesn’t. It scrambles the radio programming info on the 25W. I mainly bought these so that I could recommend low-cost solutions to new hams if they worked out. Now that I know about the Chirp problem, I’d probably recommend the BTECH 25×4 mobile for a high-power solution. 

My antenna is this one. I bought it to get me over the hill behind my house so that I could check into the 9 O’clock Net. It did not disappoint. I also have a Arrow Antennas OSJ 146/440 that I just bought. I haven’t tried that out yet, but have high hopes. I’m planning to use it on my bus with my 25-foot mast that I use for Field Day dipoles.

My mast is something like this. I did not pay as much as Amazon is asking. I found it in a Boise Army Navy store for a much lower price.