E
[email protected]
- Jan 1, 1970
- 0
Hi. I recently made a small mistake. I purchased one of those probe
type "Made in China" soil moisture testers. There was a gardening
workshop, and the UC Master Gardeners group recommended the use of
these meters to prevent over or under watering.
The meter had no reading, even in soaking wet soil. It also had no
reading in dry soil. The resistance, as measured by a DMM , across the
probe tip was infinite. The meter was opened and the probe
disconnected. The measurement of resistance across the D'Arsonval
movement meter was similarly infinite. There were solder blobs and
solder spray across the front of the meter, indicating a sloppy
assembly technique. Since the case was now damaged, and the package
was long since discarded, this meter could not be returned. It is
likely that the probably now moved-on Chinese manufacturer would not
accept it back anyway.
Since the probe part looked like a battery (dissimilar metals), a
current reading was taken on the aformentioned dry and saturated soils.
A reading of 6 microamps and 700 microamps were obtained,
respectively.
Does anyone know the calibrations of the meter, offhand? Are these
rmeasured values representative of the observed range?
If a decent range can be provided, the meter (without the movement) may
be salvageable.
Thanks,
Eric
type "Made in China" soil moisture testers. There was a gardening
workshop, and the UC Master Gardeners group recommended the use of
these meters to prevent over or under watering.
The meter had no reading, even in soaking wet soil. It also had no
reading in dry soil. The resistance, as measured by a DMM , across the
probe tip was infinite. The meter was opened and the probe
disconnected. The measurement of resistance across the D'Arsonval
movement meter was similarly infinite. There were solder blobs and
solder spray across the front of the meter, indicating a sloppy
assembly technique. Since the case was now damaged, and the package
was long since discarded, this meter could not be returned. It is
likely that the probably now moved-on Chinese manufacturer would not
accept it back anyway.
Since the probe part looked like a battery (dissimilar metals), a
current reading was taken on the aformentioned dry and saturated soils.
A reading of 6 microamps and 700 microamps were obtained,
respectively.
Does anyone know the calibrations of the meter, offhand? Are these
rmeasured values representative of the observed range?
If a decent range can be provided, the meter (without the movement) may
be salvageable.
Thanks,
Eric