Radio transceiver circuit - contactless connection of antenna to receiver or sender

摘要

The transceiver has electronic switches allocated to the connections, made conducting or blocked by a reversible control d.c. voltage. The switch in the connection between sender and antenna consists of two PIN diodes connected in parallel and in the connection between the antenna and receiver of one PIN diode. The junction point between switches and antenna is earthed through an h.f. choke in series with a resistor. The resistor value is such that about half the control d.c. voltage drops across it.