14.
Determine if the sample read in Step 13 is acid or alkali and record your answer on the
TRS.
15.
Depress the STANDBY pushbutton (figure 19).
Figure 19
16.
Rinse the electrode with distilled water and wipe it before proceeding with the next
measurement.
NOTE:
STANDARDIZATION MUST BE ACCOMPLISHED FOR EACH BUFFER
PRIOR TO READING SAMPLES OF THE APPROXIMATE SAME pH.
17.
Using the buffer pH4 and the fixer sample repeat Steps 7 through 16. Then continue
with Step 18.
18.
Leave the STANDBY pushbutton depressed.
19.
Slide the sleeve over the filling hole.
20.
Immerse the electrodes in clean distilled water (figure 20).
Figure 20
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