BUILD A T.T.M.L.

What is it? It’s a “Tic Tac Meter Loader” – a device to test your airborne battery packs under a load at the field. While nothing will replace good sound battery maintenance such as cycling, this simple unit will tell you if you got a good charge last night, if it’s still safe to get one more flight in, and when to pack it in and go home. A simple design by the Battery Clinic guru, Red Scholefield. http://www.rcbatteryclinic.com/

Here’s what you need: An empty, clean Tic Tac breath mint container (flavor optional), a pair of jacks suitable to accept you probes on your digital multi meter, a #44 light bulb, and a male plug for the type of radio you have. The bulbs are available from Radio Shack and jacks are available from any electronic supply house (try http://www.mouser.com)

At the bottom of the case, drill a hole and bring your radio lead out through a small grommet. Mount your jacks in the cap, add a short wire, then solder the #44 bulb in PARALLEL with the wires going to your plug.

When you plug your multi-meter into the T.T.M.L and the plug into your model’s charge jack, the bulb will light and the voltage you read will be your battery pack under a 250 mAh load. The load will dispel any false readings you might get from a dry or weak battery cell. Here are some target numbers to look for:

4-Cell Pack 5-Cell Pack

After charging .

& before flying: less than 5.0v. less than 6.25v

means a BAD pack

After flying, a

reading of: 4.8v. or greater 6v. or greater

It’s O.K. to continue

When reaching a

reading of: 4.6v. or less 5.75v. or less

GO HOME!