Data transceiver for commands in remote control systems - has gain controlled amplifiers keeping voltage in coupler filters level and uses same frequency for transmitting and receiving

摘要

The data transceiver, which is used for instructions and commands in remote control systems, uses the same frequency for transmitting and receiving and transmits only in one direction over a two-wire line. A BP filter (3) is connected to the 2-wire line via a coupler (4). The output of the BP filter is connected to two amplifiers (1, 2) and the amplifiers can be switched in and out. The gain of the two amplifiers is controlled (St) by a signal characterising transmitter or receiver readiness and is arranged so that roughly the same signal level appears at the BP filter for both transmission and reception.