S/W 2.10 options for the vacuum desoldering pump (on H/W 2.1S):
13. Desolder Mode -> INCHING or VALVE
INCHING mode, the handle shake switch turns on a vacuum pump motor, for T seconds.
VALVE mode, the handle shake switch turns on a vacuum solenoid valve, and the pump motor- which runs for T seconds extra for the reservoir tank.
I think you can connect a (wand) pushbutton in place of the shake switch.
14. Pump Set -> On Time -> 30 sec.
edit: Found a schematic for adding these pump features to older controller boards and more info.
Older STM32 T12 2.1S controller blank PCB is available as a
shared project over at PCBWay, if you want to build one. Same schematic as what I posted earlier.
I find the KSGER store on Aliexpress is expensive, but the quality is very good for the stations. A few accessories, like the stands are a complete ripoff and don't fit anything very good.
Aluminium FX9501 handle is really good. The T12 tip does not stick out so far like other handles, so it (handle) gets warmer. It's aluminium tube and silicone cable and grip.
Have not found a stand that really works well, it has a 16mm collar 2mm thick at the end. I might have to CNC machine something.