Re: Replacement Electrode for CHECKER 1 pH Tester

Be sure to buy it from a place that has fairly rapid turnover, as they don't have a great shelf life.

And my advice would be, unless you experience has been markedly different, to not bother with this new probe and invest in a better meter that has a better probe. My first Checker1 probe did not work well at all (had been on the shelf far too long before I purchased it) and the replacement I bought worked great -- but only for about a year and a half before it went completely haywire, in spite of being stored properly in the recommended buffer solution. All the advice I've gotten is that the probe is the most important part of a meter and the Checker1 probes that you can get for as low as 12 or 13 bucks (US) just won't cut the mustard for long.

I'm still a little wary of Hanna products given that they sell a product that from my experience is so unreliable, but people seem to have had generally excellent experience with the pHep5 and so I'll probably be buying one of those real soon.

Richard

How are you calibrating it?

You use a 7 first, then a 4. I then compare to a 10 and 3, all (3, 4,

7, and 10) come out in spec for me... The 7 sets the offset of the probe; the 4 sets the slope of the line. Both are necessary to calibrate it. I use some Potassium Bitartrate in distilled water for a 3.55 sometimes too, just make sure you use more than can disolve in the water.

Are your buffers moldy? If so, they need replaced.

I may be able to help if you give me additional details if this was not enough. Regards, Joe

Tech support thought it was a dirty electrode... got some cleaning solution and will try again tonight and report.