The case against synthetic voltage

When attempting to power sensitive electronics, i.e. receivers and servos directly from the propulsion battery we have had several major issues and they all revolve around the motor and controller. Several things are happening all at one time and can cause many different symptoms and makes it very difficult to diagnose the problem. The first thing that we noticed that cause a problem is the voltage spikes when loading and unloading the motor. We have seen voltage change as much as 3 to 8 volts with load and a great big spike when the load suddenly goes away. I do not have to tell you what happens to performance of most electronics with large voltage swings in short periods.

The next problem related to voltage is the continued drop in voltage and increase in current during the period of performance and the loss of power to the servos. The other problems we have encountered is the switching power supplies in BEC’s and the chopped power reaching the servos and receiver. We have had many unexplained gremlins in our systems when getting ripple in the power to our systems. Our solution is far too expensive for modelers and more complicated than most would be willing to proceed with. If there is sufficient space and allowance for an extra ounce, the best solution we have found is to use a separate power supply (battery) for the servos and receiver. That has increased our reliability many fold and reduced the overhead in both time and money.

- Project Manager, United States Naval Research Laboratory