A probe having at least one conductivity cell defined by a pair of electrodes formed as printed circuitry on a substrate of insulting material such as a printed circuit board. The probe is adapted to be immersed in the solution to be measured, and may or may not include a thermistor on the substrate to compensate for variation in solution temperature. The exposed area of the electrodes and the distance therebetween can be accurately and precisely controlled to provide consistent cell constants in probe manufacture.
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