Hi
Thorvald,
I don't remember if you can actually calibrate the tubemeter, but to change settings you will need your computer running. You have to connect the tubemeter via USB and use an older version of Aquasuite which you can find here:
http://www.aquacomputer.de/software.html…tup_4.72.00.exe
The red light does not mean anything if I remember correctly, you can turn off the blinking from the Aquasuite once the tubemeter is connected over USB. You can also set some data logging and adjust the emergency shutdown settings (for those to work I think tubemeter has to be connected via USB and Aquasuite has to be running).
Kind regards,
Boris.