Using a Modified Marine Battery Box
Living in the city lights I need to travel a bit to find dark skies. While some on my local haunts,
such as Withlacoochee River and Chiefland, have AC power available others, like Crowley, don't (at least without a 1,000 ft extension).
Portable 12v power seemed like a reasonable solution. Back in 2003 I considered the commercial astronomy power packs on the market bit felt that their
cost was too high for the small amount of power that they offered. Dew is a big problem in Florida and the dew heaters get a workout. Twelve volt deep cycle
batteries were easy to get locally and all I needed was a box to put it in. Poking around the web I saw some great ideas for building wooden
battery boxes. My concern was making them rain proof enough to handle the Florida monsoons. I decided to start with an $8 marine battery box
(that was the 2003 price. In 2024 about $13) from Wal-Mart and it worked so well I ended up building three of them.
All modifications were made to the removable lids of each box. The basic version has two 12v lighter sockets
each with its own fuse protection (a must!!). For the lighter sockets I chose a marine version because it is rust resistance and has a built-in flip-open cap.
Beside each socket is the fuse holder for that socket. Don't rely on each item plugged into the box has its own fuse. Add the fuses to the box even if they
are inline inside the lid and keep a few spare fuses in the battery box if there's room (I use an old film container). The red rectangles are reflective red tape.
Since I took the inside lid photo I added another lighter socket and fuse to it. One for the G11 mount, One for the ASIAir Plus and one to charge a cell phone
with a small car charger plugged in.
Inside of the lid after 20 years in January 2024. Further down is the updated lid wiring in May 2024 where 15v output was added.
Inside the lid is a marine power block (you could use a crimp to save some cost) that ties everything together.
I use Outdoor Goop to seal everything and prevent the wires from moving around. I was amazed at how well it sticks to the black plastic of the box.
The 5A fuses may need to be adjusted as needed. If your go-to motors have a maximum combined draw of 5A you would likely want a 6-10A fuse so that you are able
to slew both motors at the same time.
Below is the first lid that I made and it has some bells and whistles. I added a volt meter, On/Off switch and a
red LED and three 12V sockets. Later models used the battery clips as the On/Off and I picked up a battery tester that plugs into the lighter socket
to test voltage. The LED works great, but was never used. It has been in use now for over twenty years without a problem. The photo below is from 2024.
