Two things are demonstrated here: using the Trigger Master to reduce RoF (motor speed), and make 2-round bursts (instead of the default 3-round burst).
Reducing motor speed means a lower Rate-of-Fire. This can be useful to get more authentic rates of fire from guns (many airsoft guns fire about 900rpm, when a more realistic RoF is 600-700 for most rifles. Some WWII subguns like the MP40 fired around 500rpm.)
Reducing RoF by electronically lowering the motor speed is the best way to do it. It maintains motor and battery power, and maintains a STABLE speed! The other way to reduce RoF (with a low-capacity or low-voltage battery) just means you get less motor power, unstable speed, and a quickly dead battery!
A 2-round burst is more authentic for guns like a UMP (which actually have 2 round bursts in the real versions).
Of course, you could also do any of this just for your own personal preference too.
To lower motor speed, it’s pretty straightforward. To get the RoF I got in the video I reduced the motor speed by 40% (4 trigger pulls in the configuration).
To get a 2-round burst you lower the burst time option in the configuration. Start with about 15-20 trigger pulls, then try firing a burst. If you are now shooting some 2 and some 3 round bursts, you need to reduce it some more. The more bursts are 2-shot and the fewer are 3-shot, the closer you’re getting to the right number. Reduce the burst time until you’re consistently shooting 2 round bursts. (I get a 3 round burst every 5 or 6 times, but I consider that “good enough” and left it at that).
The Trigger Master will remember any settings you change in the advanced configuration.
If you ever get screwed up and want to do a full reset (reset back to factory defaults to start over again), just pull and hold the trigger after the six vibrations in the advanced configuration. Consult the full documentation for details.
After the full reset, disconnect and re-connect your battery and fire 5 shots in semi-auto. The Trigger Master will now be completely reset (it forgot anything you changed in the advanced configuration) and will be trained for your gearbox timing — ready to start again from square one.
You can’t break your Trigger Master by playing around in the advanced configuration. Worst case, just do a total reset to forget everything you did and go back to square one!
YouTube Video Demo: