Hand held TDS meter options

[Myka]

I currently have an HM Digital TDS-3 meter and I despise it. It is horrible to try to calibrate with the screwdriver that you move a billionth of a mm and the meter goes up by 50 ppm. The Hanna TDS-1 uses the same type of screwdriver calibration. I'm looking for something easier to calibrate.

The only hand held TDS meter that I know of that doesn't use a screwdriver for calibration is the HM Digital COM-100 meter. It is also top of the line, and rather pricey.

Anyone know of any other TDS meter that doesn't use that stupid screwdriver calibration?

EDIT: Just found the Hanna HI 98311 Waterproof Low Range meter self calibrates like their pH meters. Excellent! However, just as pricey as the HM Digital COM-100 meter!

EDIT 2: The Hanna Primo has automatic calibration with 1382 ppm fluid. It suggests 2% +/- accuracy, but I wonder how accurate it is when it is very close to 0? I will send email. This meter is only $20.

[Binare]

Walmart in the rv isle, costs 10 or 15 bucks if memory serves me correctly.

[Myka]

Originally Posted by Binare

Walmart in the rv isle, costs 10 or 15 bucks if memory serves me correctly.

How is it calibrated?

[sitandwatch]

The Walmart one does not have a calibration, turn it on stick it in the water and you get a reading.

[Myka]

Originally Posted by sitandwatch

The Walmart one does not have a calibration, turn it on stick it in the water and you get a reading.

Hmmm...I don't like that idea.

[Binare]

You hold the button till it reads zero, then put it in your water. Not entirely sure why calibration is necessary on some these. Out of liquid it should always read 0. The walmart one works good enough for our needs, filter replacement.