Tandem match TX-RX unit for LDMOS MOSFET tube amplifier 1200W
TX-RX unit is intended to provide the switching of amplifier between receive and transmit modes.
Input signal is PTT line from transceiver.
When PTT input goes low, the relays directs the signal from transceiver to PA input and from PA output to antenna. When PTT is high (RX mode) the antenna is connected directly to transceiver.
The second tandem match is used as a high SWR detector with incorrect, spontaneous switching, failure of the LPF.
More than 50% of the transistor amplifier failure occurs due to incorrect or spontaneous switching of the LPF.
When there is a spontaneous switching of the LPF, which depends on the interference to the band decoder, transceiver, computer, etc., then the combustion of the transistor happens. The leads disappear right after that. You can not find the problem.
You need to have control over the state of the LPF.
Size 130 x 70 x 25(h) mm