Compact 12-Volt Power Center
Joe Beshar
You will find this compact 12-volt power source ideal for charging your electric-model batteries right out on the flying field, without the hassle of having to go back and forth to your car for a charging source.
A photo shows men carrying the power center along with the flight transmitter resting at its side, grasped by the transmitter handle, conveniently freeing the other hand to hold the model. Now, isn't that compact? One trip from the parking lot to the field to get to your flying.
The unit is nine inches wide, 7½ inches deep, and 10½ inches high, and weighs only 9½ pounds.
At the field the power center is not only useful for charging your electric-model motor batteries with the 12-volt power available, but also for running a retract air compressor, peak-charging of receiver and transmitter batteries, running an electric fuel pump, running a glow-engine starter, or charging a glow-plug lighter Ni-Cd battery.
The condition of the battery in the power center is displayed on the test indicator panel. Three lights on is normal; two is low; and one on is "dead." When charging is required, the power center battery can be charged while driving to the field or at the field by connection to the power receptacle on your car dashboard.
Construction
Wood required is a 20 x 24-inch piece of 1/4-inch plywood. I used lauan; a 2 x 4-foot piece costs less than $5 at Home Depot. A piece of 3/4-inch pine 1 x 8-1/2 inches serves as the handle and 7 x 8-1/4 inches serves as the base. Detail dimensions are shown on plans.
Assembly is started using Elmer's carpenter glue as the ends are clamped square (this glue is used throughout construction).
A photo shows the battery location with battery base position holders screwed in place and the handle and side panel, which need to be glued. Also shown is the shelf, which is installed on top of the battery. Note that this panel is not glued but press-fit so it can be removed in the event that the battery needs to be replaced.
Finish using water-based polyurethane; any other durable finish may be used if desired.
A photo shows the wiring and assembly with shelf and handle removed for clarity; note installation of power output poles with charger alligator clips in place (Radio Shack fuse holder 2700364 and rocker switch 275-694).
Velcro® is used to hold the charger in place and a steel plate attracts the magnet under the test indicator to hold it in place.
Joe Beshar <REDACTED>
Transcribed from original scans by AI. Minor OCR errors may remain.
