ARES Boom Box
This ARES Boom Box is based on the wiring design of WX2NJ's original boom box. The transceiver is a Kenwood TM-D700A which is a VHF/UHF dual-band radio with a built-in packet TNC. Also, since it has a remote control head I added jacks on the outside to plug in both the panel and the microphone. A couple of other innovations are Anderson Powerpole outlets for 12 vdc out plus a car lighter socket that accommodates a small goose-neck light or other equipment.
The links below the photo lead to other more detailed pictures taken during the construction of the box. The hardest part of this project was planning component placement. There were lots of inter-dependencies and I would have found it helpful to look at a few other examples during layout. So maybe somebody will benefit from these photographs.
Important Update: A cardinal principle of engineering is that every thing can be improved and the ARES boom box is no exception. I originally built the box in 2004 and have used it for special events and Simulated Emergency Tests (SETs). Almost as soon as it was finished, I started making modifications. Three specific changes matter a great deal to anyone else contemplating construction of such a box.
First, the little LED-based battery voltage indicator is totally inadequate. It simply doesn't have sufficient resolution to help me monitor the true condition of the batteries. To fix this short-coming I simply wired in a small DVM that I bought at Harbor Freight for a few dollars. It's held in place under the lid by two tie-wraps.
Second, and of very great importance, I added a battery booster. The two gel cells are each rated at 6 volts. They're wired in series to produce 12 volts. Unfortunately, even at over charging them to 13.8 volts, I found they lost voltage so readily that my Kenwood TM-D700 quickly became unusable. Indeed, I'm not terribly enamored of the TM-D700 for a number of reasons; one being that it gets flaky by the time my supply hits 11 volts. That's not much headroom when running off of a 12 volt source. So the battery booster solved that problem. I bought the little unit from W4RRY that is advertised in World Radio and listed at http://members.cox.net/w4rry/index.html . It has served well. The booster is also fastened underneath the lid and is held in place with two small bungee cords. Here's a photo of the changes.
Finally, the charging circuit wouldn't get the batteries even to 12 volts. So I've been forced, in practice, to charge the batteries with a normal automotive battery charger. To fix that issue I purchased a PG40 PWRgate from West Mountain Radio (http://www.westmountainradio.com/PWRgate.htm). I have not installed it in the boom box, however, and that leads to another discussion.
I like the boom box, have used it several times, and will undoubtedly use it again; however, with experience my philosophy has evolved. Were I starting over, I'm not sure that I would build a boom box at all. I now believe that it would be more effective to build a mobile power station on wheels, either a self-contained wheeled container or one on a small collapsible hand truck. The foundation would be a deep-cycle marine battery and a commercial 13.8 volt RF clean power supply that are connected via a PWRgate. Then I'd use a battery booster to supply the transceiver. I would also integrate my 120 VAC inverter to potentially run my laptop (for WinLink and packet) along with a small inkjet printer.
In practice the radios are portable; it's the power that's heavy and awkward to transport.
