The only reason to cycle either NiMh or NiCad is to check to see if they are still up to capacity, maybe once or twice a year. The way the batteries are used in transmitters and receivers never creates the so called memory syndrome which is pretty much a myth anyway. If you are using the slow chargers that usually come with the transmitter/receiver package, just charge over night before the fly day and enjoy. No need to discharge first either even if you never flew since you last charged them. As to discharging by turning on the transmitter and letting it run, there are two cautions. Do not run for an extended time with the antenna collapsed as it may damage the output stage as the energy normally radiated as RF is now dissipated as heat in the output stage. If you run with the antenna up, make sure there is no one else within two miles trying to use that frequency while you polluting the airwaves with needless RF.