A transmitter system for wireless communication with implanted medical
devices includes a transmitter circuit having a resonant network the
resonant frequency of which is adjusted by a feedback circuit in order to
minimize the current drain from the power source and maximizing the power
source life. The transmitter system may be powered by a power supply
block which uses commonly available RS-232 signals of a host computer as
a raw power source, combined with a high value storage capacitor to
provide power for the wireless medical data programmer. A feedback
circuit monitors the charging current as well as voltage impressed across
the storage capacitor in order to maintain the charging current at
maximum level during the charging time and in order to stop the charging
once the full charge of the storage capacitor has been reached.