The cloth junction is a piece of fibre/cloth that interfaces the electrode to the meter. The 'cloth' can sometimes become dirty, moving it around can rejuvenate an electrode - don't ask me how, I assume it remakes the electrical connection by being moved.
The instructions I received with mine don't mention the junction at all, and there are no bespoke replaceable parts for it. I assume that if you were to order a replacement electrode then the cloth would be packaged with this? I'm not going to open mine until I have problems, the old adage ' if it works, leave well alone!'.
I have not checked my calibration for two weeks, just done one now and it's 7.05 @ 22.5 deg C
I think I can live with that little rise.
How are you getting along with your Hanna Meter, Peat? I had to recalibrate mine after only ten days or so, the readings went 0.5 high.Glad you mentioned using the 4.01 buffer for storage, one place I shopped said to use 7.01 but I went with the 4.01 on your advice. Found a MSDS sheet for the storage solution and it has a PH of 3.5. Hope I don't have to recal every two weeks but it's easy enough. Otherwise, this is a fine piece of equipment, I use it right alongside the Bluelab almost every day and they both take about the same amount of time to get an accurate reading. Thanks for the info!
Oh, do you have any clue what the "cloth junction" in the sensor is and how to pull it out 1/8" every now and then? I can't find any info about it other than the replacement probes mentioning it.
You can store it with pH 7.01 but the Hanna customer service chap told me it was better to store it with 4.01.
They do a storage solution, which I ordered but was out of stock. I e-mailed them asking if it was OK to store at 7.01 and they said use 4.01 I bought the bottles of pH buffers, I felt that they would be cheaper in the long run and I could dictate how much I wanted to use.
I read the manual on yours a few days ago and was also surprised by the difference. I don't know if I have a bad unit or it's just lousy but I'm going to return it, the readings are all over, it showed distilled water at 8.8 then 7.2 then 8.8 again within a few hours. I found a nice price on your Hanna here so ordered one with sachets of 4.01 & 7.01cal solutions. If I read correctly I can store it with 7.0 PH solution in the sponge, correct? I have two different ways to measure PH and now don't trust either. Hate it when that happens.
Interesting how your manual says to use distilled water to store your tip. My manual, in large bold letters, says do not use distilled water to store the probe tip - always use the storage solution or pH 4.
When I have finished with mine, all I do is rinse under normal water and shake the excess off. Place the unit back in it's cap (with sponge) and that's it - no wiping round with a tissue. The glass electrode should never be allowed to dry out, by blotting with paper isn't this going to dry it out? As well as possibly damage it? Oh well, that's what you manual says (bedtime reading for me , need to get out more!), so it must be right...
I'm going to give mine a couple of weeks before I check the cal again, see how stable it is.
This is for sure the best place to grow cukes, Beth. I'm sure you've read Peat's glog, he's doing great just using an AG Classic. If it continues to take over his house maybe he could train some tendrils to be cup holders or train a big loop, top it with plexiglass and have a new coffee table.
Peat, I hit the poor li'l hydro store down the street and they had one PH meter - only one, poor guys. They sold me this one for $40 plus another $10 for 8oz bottles of 4.0 and 7.0 cal. solution. I dip it in the solution and stir then try to read the tiny LCD readout (no memory so I have to do some contortions). When I'm done I have to rinse it in distllled water and blot everything with a tissue, The little glass electrode is way over on one side and it's hard to get a tissue around it. There's a sponge in the electrode cover that is kept slightly damp with distilled water. There's no auto-off so I have to remember to turn it off. All in all it's not bad for $40 but yours is head and shoulders better.
I used the tube and drops kit to test the 7.0 solution and it reads ~6.6. Distilled water read 6.8 while the meter showed 7.2. Quite a difference.
Bruce - this one has a compartment in the lid with a piece of sponge. You soak the sponge in the buffer, usually 4, and simply place the instrument back in it's protective cap, the sponge keeps the tip wet.
Beth - you have come to the right place to grow cukes.
Thanks for the comments. I've been back and forth. I think for my purpose, a separate EC meter makes sense. pH strips are fine for the readings we need. No sense getting too complicated from the get go! Heck - I just want to grow cucumbers!!
Nice one, Peat. I like the self calibration and accuracy. How do you store it? I may just have to make a run to the big hydro store and see what they've got. I haven't had a new gadget all week, my $6 kit is past half gone in only six months.
It's a Hanna model, waterproof (much safer in case I drop it in the water!) and temperature compensated. For the 'ultimate' calibration you need two pH buffers, 7.01 and 4.01 It will work perfectly well on only the one buffer calibration though - pH 7.01
Buffers are generally available in pH 7 & 4, this one, for some reason, uses 7.01 & 4.01
The calibration procedure is simple with this model, just put it in the relevant buffers and it sets itself up - no manual adjustment required. Calibration is only once per month, I find it much simpler, quicker and less messy to use than the liquid & chart. I held of buying one for now as they won't last forever, at some stage the tip will need to be replaced and it's essential that it's stored correctly - if the probe dries out then you could cause damage, treat it well and it will last though.
Always buy one with a replaceable electrode, stay away from the cheaper ones without this - if they go then all you can do is put them in the bin!