Speed Controller Adjustments for Droid #2, Power for Switch 15 for Droid #1

With droid #2 inheriting droid #1's transmitter/receiver, I needed to recalibrate the Sabertooth 2x32 speed controller settings to match those sent by the 10CAG transmitter. I never did calibrate this transmitter with the Sabertooth 2x32 speed controller on droid #1, instead using trim values to make adjustments. With Dimension Engineering's DEScribe software, I can tune the speed controller so that its expected min/neutral/max servo pulse settings match what the transmitter is sending, and zero-out those trim values once and for all.



Nominally, the minimum servo pulse setting should be 1 millisecond, the neutral/idle position should be 1.5 milliseconds, and the maximum servo pulse setting should be 2 milliseconds. Using the DEScribe software and the associated Device Monitor application, I can see that these values sent by my transmitter for the steering and throttle channels are actually a bit outside those values. I jotted down what the Device Monitor application reported for each of those settings, and used DEScribe to program them as the expected values. (This will be need to be done for droid #1 and its new radio as well.)



Next, I worked on getting power to Mike Senna's Switch 15 box for droid #2. The electronics in this box run on 3.3 volts. There's a voltage regulator in the box that can downstep 6-28 volts to 3.3 volts. The trainer port in the back of the Futaba trasmitters provides power on the middle two of its six pins (negative on the center-top pin, positive on the center bottom pin). In the case of the Futaba 10CAG transmitter, 9.6v are supplied on these pins when the transmitter is turned on. I purchased some connectors for the trainer port a while back, so I grabbed my last spare and soldered it up.



Good to go, for droid #2 at least. I actually already had this set up for droid #2, but the trainer port on the new Futaba 14SG transmitter was somewhat finicky in accepting the old connector cable I made for droid #1, so I transferred the cable for droid #2 to droid #1, and made this new cable for droid #2.

Also note that since the new Futaba 14SG transmitter for droid #1 runs on a nominal 6.0 volts, and that's the minimum that the voltage regulator in the Switch 15 box is rated for, I plan to replace that regulator with one that matches the 14SG's voltage.