The problem is that you have no way of knowing if you got a bad bottle or not, or, how bad it is, especially if it's not so WAY bad as to be totally unbelievable like that bad one I got.
A 'single' bad bottle in a batch number that is supposedly good indicates a quality control problem. EVERY bottle should be checked before shipping and was obviously not. The means of checking [at least for comparison] came in the form of a metalized plastic sachet of sol designed to be the test container. [Cut off top and insert meter] When using the sachet as intended, the uS reading quickly rose and rose with no end in sight. When I filled a plastic baggie with that calibration solution and tried again, the reading quickly dropped and stabilized. But since the original package had apparently contaminated the sol when the electrical current from the meter hit it, the baggie test is worthless. Good Solution/ Bad sachet? Something is seriously wrong there. There is a table of uS to temperature relationships on the calibration sol bottle. If the PWT is temperature compensated as claimed, why would this be relevent? ..and if it's not...? No instructions concerning this that I have found. On the other hand, the factory calibrations seem to be pretty consistant over several years time. It "used" to be "certified" but isn't any longer. I seriously doubt that Hanna uses a calibration solution to adjust their meters at the factory. PWTs are pretty good instruments but a calibration difference of +/- 4 or 5 uS, while probably not a big deal for their intended purposes and still useful as a comparison between batches for a single individual, is a major problem when people in different locations..measuring different things with different meters...get riled up beause their meter isn't saying what they think it should. I use an auto off that's keyed to a voltage/current/conductivity relationship. The CS always reads virtually the same uS at shutdown for me, using my meter, regardless of which of many generators I used to make a batch. But now and then, someone can't get a reading of more than 6 or 7 uS. In every case, they have recalibrated their meters. All I can tell them is send me your meter and I'll see if it reads the same as mine in the same liquid. I STILL can't say which one is correct. I can make their generator make their meter read anything they want it to... and vise versa. I could make a batch and send it to Frank Key and get some numbers and take those conductivity and total silver content numbers on sheer faith as being correct. That might be useful, BUT, CS changes with time and I've had batches change from absolutely colorless to pale yellow in transport with all that vibration and temperature shifting while in airplanes. As we all know by now, agglomeration changes uS readings and they will invariably drop a couple to several points overnight. [ total silver content doesn't change] I have a big batch sitting here stabilizing now. In a week or so, I'll send it to Frank. Hopefully it won't change in transport and I'll be able to tell smaller lies. [But I STILL may not know how big they are.] Another portion of the same batch will go to the local NCDNR water lab in Raleigh NC [Depending on the state of my friendship with a receptionist there who will sneak it through under the table because the NCDNR lab ONLY does state work and nothing for the public] This time, I'll ask what process they use to test it. [Maybe I should air mail it to myself first?] Just before sending the samples off, I'll meter it with two PWTs. One PWT with the factory calibration and one that has been re-calibrated with the 'good'? calibration solution. BTW, I won't be using that data to 'contest' Franks data because I still won't know if either of them are correct if they are different, or which one is correct.... if any of them are. Putting anyone 'on the spot' is not my intent. Humm. I think there's enough to send some to Ole Bob too. Thing is, till I get at least two people to agree on 'something', No one can claim anything. So far, no good. Ode At 03:20 PM 10/10/2003 -0700, you wrote: > >----- Original Message ----- >From: "Mike Monett" <31dtzj...@sneakemail.com> >To: <silver-list@eskimo.com> >Sent: Friday, October 10, 2003 1:41 PM >Subject: [silver_list] Re: CS>Re: Measuring very high ppms > > >> >> The Hanna PWT would be an excellent method if I could find some way >> to guarantee the calibration. Steve Young's idea to make resistive >> standards might be an excellent solution. > >> Mike Monett > >Mike, > >The meter can easily be calibrated if you use the calibration solution from >Hanna. I got one box of 16 bottles of solution that was defective and Ken >got one of the bottles. It was the only batch I have gotten that was >defective in many years. I think you can generally trust the solution to do >what it was intended to do....allow calibration of the PWT. > >It will be very difficult to use a standard resistor since the sensing >electrodes are not easily accessible and the meter would have to be >disassembled to get at the electronics. Not something the average person >would want to do. And it's really not a good idea when all one has to do is >use the factory solution. > >Trem > > >> >> >> -- >> The silver-list is a moderated forum for discussion of colloidal silver. >> >> Instructions for unsubscribing may be found at: http://silverlist.org >> >> To post, address your message to: silver-list@eskimo.com >> >> Silver-list archive: http://escribe.com/health/thesilverlist/index.html >> >> List maintainer: Mike Devour <mdev...@eskimo.com> >> >> > >
