7
The SoilStik automatically recognizes buffer solution
pH’s of 4, 7, and 10. Buffer solutions of pH 4 and 7 are
included with the meter. Although it is possible to cali-
brate to all 3 values, a two-point calibration with a
buffer of 7 plus 4 or 10 (whichever is nearest to the ex-
pected sample value) is always recommended. A one-
point calibration (with a value closest to the expected
sample value) is also valid. For best accuracy, always
calibrate at the sample temperature.
Calibration Procedure
1. Put a small amount of buffer solution in a small plas-
tic cup (provided). For multi-point calibrations, pH 7
should be calibrated first, followed by 4 and/or 10.
Place the electrode into the buffer solution and momen-
tarily press the
CAL/RECALL
button.
2. The SoilStik will automatically recognize the calibra-
tion solution. After the
CAL/RECALL
button is re-
leased, the LCD will display
CAL/RECALL
. The pH
calibration value will then flash on the LCD.
3. When calibration is complete, the SoilStik automati-
cally displays the
END
symbol and returns to normal
operation mode. Note: If the calibration solution is more
than 1 pH unit different from pH 4, 7, or 10, the SoilStik
will assume an error has been made, abort the calibra-
tion and return to normal operation mode without
changing any internal calibration constants.
4. The appropriate circled indicator ( , , or ) will ap-
pear on the LCD when a calibration has been com-
pleted with a given calibration buffer solution. The cali-
bration constants are stored until a new calibration is
performed.
5. For a two- or three point-calibration, repeat steps 1
to 4. As additional calibrations are performed, addi-
tional circled indicators will appear on the LCD.
Calibration