4 Event Sequencer by US4ICI

The 4 Event Sequencer for transverters and power amplifiers (PA) is designed by US4ICI.
You can buy it in my Online Store or on eBay.

This 4 event sequencer has four outputs which able to sink up to 100 v at 7 amps and another output up to 30 v at about 10 amps for LNAs. Each output is protected from transient spike. The delay is adjustable (R4 on the board) from the few milliseconds to seconds. The board has the LED’s allow a visual indication of timing for each port (event).The sequencer use a ground for PTT activation and simply can be activated from any transceivers or transverters. Each board is tested and ready to use. You just need to adjust the desired delay.

  • Technical characteristics:
    – Board Material: FR4
    – Output: 7 A (max)
    – DC voltage: 12 – 30 V
    – Dimensions: 65 mm x50 mm
    – Assembled in Ukraine

The sequence is following:
TX on RX off (PTT to ground)
EVENT 1 (active ground) -> EVENT 2 (active ground) -> EVENT 3 (active ground) -> EVENT 4 (active ground)
RX on TX off (PTT not connected)
EVENT 4 (active OFF) -> EVENT 3 (active OFF) -> EVENT 2 (active OFF) -> EVENT 1 (active OFF)

On this picture you can find the typical connection of sequencer board:

The power line of LNA should be connected to port which labeled TO LNA (look at the picture). This output does provide +12 V (same voltage as on VCC pad of sequencer) on RX and 0 V on TX (PTT active to ground). Do not use this port for something else beside the LNA power. If you need other than 12 V
coming from LNA port you have to remove the jumper (0 ohms resistor circled on the picture) and supply your desired voltage to point A. Do not exceed 30 V.
The sequencer board could work from 12 V to 30 V DC.

All boards that I have in my store are assembled, tested and ready to use. There is no tuning required unless if you want to change a sequence time.
I recommend to perform a PRE-CHECK before installation.
The Pre-Check is :
– apply voltage to the board at GND and +12 V points
– connect the PTT to ground and verify the TX sequence (listed above)
– verify the sequence on RX
– adjust a delay if it needs
– remove the DC power

This simple Pre-Check will show you how board is works. I have some cases where buyers damaged the board before installation and then reported the bad board. I strongly recommend to use a DIOD across all relays that you want to control from this sequencer. It will protect the board and save your nervous system.

Questions are welcome 24/7.

Alex K6VHF

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.