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Leaving RC transmitters on for long periods of time with the antennas retracted or collapsed, as shown, is a bad idea.

Q-9: When I get home from the flying field I usually leave my transmitter and receiver on for approximately eight hours, until they are almost completely discharged. Then the night before I fly I recharge using the RC manufacturer’s charger for 15 hours. Is this a good process?

A-9: I’m not in favor of your process at all! Leaving your transmitter and receiver on for eight hours will probably take the batteries all the way down and they might even go into reversal. That fact alone could easily ruin a battery pack.

I assume that when you leave your transmitter on for that long period, you have the antenna retracted or collapsed. If so, the transmitter output circuit is detuned and the output current may be exceeding normal operating parameters. Therefore, you are doing your transmitter no good in this regard.

On the receiver side, as the batteries wear down the servos will get jittery. Then later the control may go hard over, resulting in a stalled servo or more likely a damaged servo gear. In both cases, the only way to discharge a battery pack, be it transmitter or receiver, is with a standard discharge or cycling device.

These units are set to cut off or stop discharging when the voltage gets to something near 1.0 volt per cell. By using such a device you will never take a Ni-Cd or NiMH battery down too far! But even more important, you shouldn’t be taking your batteries down after each flight session. The so-called "memory effect" has always been a debatable subject.

The best recommendation is to cycle or discharge-test your battery packs every month or two. Your way is unnecessarily losing you a great deal of battery life.

—Bob Aberle