This is event sequencer for proper RX to TX transition, and the return to RX mode. This sequencer based on modern STM8s CPU. Internal CPU clocking guarantees high precision and long-term stability, NO CAPACITOR, no external timing network, everything is digital. Sequencer has four high current MOSFET switches on output, they switching in 3 step (stage) with delay. Delay time can be selected by onboard jumper from two values – 15ms or 45ms.Three of MOSFET output port is “OPEN DRAIN” and “ground” active. Fourth MOSFET output port has external DC +12-30 input line (+IN) that switched ON (to +OUT line) in RX mode and has same timing diagram as stage2.
Output ports not protected, just BARE DRAINS, so – be carefull, don’t forget to use diodes in parallel with relay coils.
Sequencer can be switched to TX or RX mode by two ways – by external footswitch or from USB. You can use USB TX/RX switching from PC with any amateur radio software via RTS signal of virtual COM port. Sequencer uses CP2102 as USB to COM interface and doesn’t require a manual Windows (for Windows VISTA and later) driver installation.
• TECHNICAL SPECIFICATION
Board size is 65 x 50 mm
Output ports: 4ports, 50v/3a max
Input ports: Footswitch, USB
Delay time: 15 ms or 45 ms, onboard jumper selectable
DC input: +9-24v/0.1A max