Telemetry system for long-duration transmission of data from a transmitter with a limited power supply, in particular in conjunction with an implantable organ replacement, with an active receiver component containing an oscillator with a first inductor which is interconnected with a detector to determine temporal changes in the oscillation amplitude and/or frequency present at the inductor, with a passive transmitter component containing a second inductor which is interconnected with a switching element with temporally variable electric characteristics, where the second inductor forms part of a resonant circuit with the oscillating circuit frequency of the oscillator as a resonant frequency.
