Thanks, but I solved the problem! The problem turned out to be an electrical earthing issue. I am measuring flowing water discharged to river. When I was running on battery power for the laptop everthing was fine, but if I connected to the mains, it all went wrong! BUT if I removed the probe from th...

HI

I am wanting to correctly measure pH via DrDAQ. I have buffer solution of 4,5 and 10.

Does anyone know how I set it up? Someone suggested using scaling and table lookup, but that is only applicable for linear relatioships?