1296MHz (23cm) Masthead Preamplifier

This project was built to replace the SSB Electronics SP23 preamplifier previously used. The SP23 amplifier can only handle 100W and was thus not adequate after the 23cm power amplifier was upgraded to a Beko HLV-350.

The preamplifier consists of a G8FEK preamplifier module together with a changeover relay capable of handling 400W. Separate feeders are used for TX and RX. The preamplifier is powered by a voltage applied by a bias-T to the RX feeder which energizes the preamplifier and relay.