By Ken Adachi <Editor@educate-yourself.org>
http://educate-yourself.org/products/tdsmeterdescrip.shtml
 

TDS stands for Total Dissolved Solids. This meter is often used by the water industry to measure the level of minerals in water, however it gives a relatively accurate reading of colloidal silver concentration in parts per million (ppm). The only way to obtain a true ppm measurement of a collodial silver sample is to send it out to a lab equipped to analyse the CS. That can be time consuming and expensive. Most producers of CS are now rating their ppm with a TDS meter and adding the nomenclature "TDS" after the ppm number. For example, 10 ppm TDS, means 10 ppm as measured with a TDS meter.  For our purposes, it's more than accurate enough. It takes all the guess work out of trying to figure how concentrated your CS solution is. This meter works equally well measuring standard DC CS or the high voltage AC CS such as Merlin's Super Silver. These  TDS model1 meters with automatic temperature compensation are brand new  from Hanna Instruments, one of best names in laboratory measuring equipment. Specifications as follows:

Range:          0 -999 ppm (mg/L)
Batteries:      4 x 1.5v Alkaline (Life approx. 150 hours)
Resolution:    1 ppm
Dimensions:  150x30x24 mm (5.9x1.2x0.9")
Accuracy:     +/- 10ppm
Weight         85 g  (3 ozs.)
Typical EMC
Operating Environment:  0-50 degrees C/ 95 % RH
Deviation:      +/- 1% F.S
Temperature Compensatrion   0-50 degrees C (41-122 degrees F).

The meter comes with a sturdy, snap lid plastic case and jeweller's screwdriver for re-calibration if desired. All units are factory calibrated and include calibration test results. To test the unit, you can dip it in distilled water up to the max level indicated on the side on the meter. You should get a reading of zero. After measuring each CS solution sample, you should rinse with distilled water in between and when finished. Available on the Products page for $70.donation plus shipping (Item #3S). See picture below: