A TRX (Transmission / Reciving ) sequencer help to protect the radio equipment from damage. If you use a LNA ( Low Noise Pre-Amplifier ) and a PA ( power amplifier ) together with your transceiver it's important to switch off the pre-amp first before applying power/ptt to the PA and TRX. Otherwise you could easily kill your pre-amp.

The right TRX sequence:

- Pre-Amplifier OFF

- COAX Relay ON

- Amplifier ON

- Transmitter ( Transciver ) ON

- Transmitter ( Transciver ) OFF

- Amplifier OFF

- COAX Relay OFF

- Pre-Amplifier ON

NB.

S1 = Power Switch

S2 = LNA ( Pre Amplifier ) Online / Offline

S3 = PA ( Power Amplifier ) Online / Offline

RV1 = Set TRX Delay

PTT = Close to ground to enable sequence

+++ Use always Coax to wiring Sequencer to Users (  RG58 is OK ) Screen is grounded !! +++

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