The DUPLEX EX line of receivers is intended for operation with DUPLEX Tx transmitter modules in the 2,4GHz band and are fully compatible with the previous version of the DUPLEX. Thanks to the fully digital and bidirectional communication between transmitter and receiver there arise completely new aspects in the model remote control branch. One of the most important advantages is the operation without crystal, moreover the low susceptibility towards interference, the high range up to the limit of visibility and the possibility to follow anytime the onboard state of the model and its functional parts. An additional satellite receiver RSat2 complements the receivers R9, R10, R11, R12, R14 and R18. This receiver is a full DUPLEX system receiver offering the complete functional spectrum of the system. Instead of classical servo pulses the output of the RSat2 receiver offers a PPM signal only. This PPM signal is furtheron processed by the receivers R9, R10, R11, R12, R14, R18 or by compatible RC equipment which requires a PPM signal at the input.