Transmit-receive aerial reversing circuit - uses inverter delay chains to control aerial and supply relays

摘要

The reversing circuit controls a change-over relay connected to a transmit/receive aerail and has a delay circuit to delay the relay such that the aerial relay operates before the relay that connects in the d.c. supply voltage when changing over from receive to transmit. The supply relay operates before the aerial relay when changing over from transmit to receive. - The delay circuit consists of several inverters forming two chains each with RC components. The first chain is assigned to the supply relay (G) and the second chain to the aerial relay (A). The charging time of the RC capacitors is much greater than their discharging time.