With no-fumes electric power, it is possible to test motor/prop/ESC combinations on the kitchen table—especially valuable during the building season here in the Midwest. To control the ESC, all that is necessary is to generate the 1.0 ms to 2.0 ms five-volt pulse that the ESC expects, using the 5-volt power conveniently provided by the ESC (intended to drive the servos in an R/C power system). A full system will include the measurement of current, voltage, power, and RPM. The photo shows such a system. The Medusa Research “Power Analyzer” continuously displays the first three parameters, and can send them to a laptop to graph and, later, print. The battery-powered light is needed to measure RPM because otherwise the fluorescent light produces its 3600 RPM.

But the same little black box produces just what the throttle channel on an R/C receiver puts out, so it can be used also to program the ESC (e.g., the Electrifly ESC is programmed for brake ON by using the sequence full throttle, off throttle, full throttle, off throttle) as well as “running up” the motor on the flight line and checking the RPM (just like the fumers).

The smarts behind this black box is the same PIC microcontroller as used with the timer/controller in the preceding thread. The LED flashes when 5-volt power is applied from an ESC. The potentiometer has a knob; at full counterclockwise it produces a 1.0 ms (0.001 second) pulse at about 50 Hz and at nearly full clockwise and beyond it produces a 2.0 ms pulse, with 0.01 increments. If anyone is interested in trying one of these boxes, send me $12.50 and I’ll get one in the mail within a day or two. (Will Hubin, 719 Cuyahoga St., Kent, OH 44240, whubin@kent.edu)