The rfRXD0920 device is a single conversion superheterodyne receiver that supports both ASK and FSK modulation formats within a frequency range of 850 to 930 mhz. The rfRXD0420 device is a single conversion superheterodyne receiver that supports both ASK and FSK modulation formats within a frequency range of 300 to 450 mhz. UHF ASK/FSK/FM Receiver