3-4
Calibrating the Model 820
Model 820 Technical Reference Manual
Step 10
Pressing the
d
key will initiate a calibration
change. Do that now:
In this screen, an error message
initially prompted for a reset(see
step 12 to reset). The difference
between the current and the last
calibration is 0 dB. If the level is
not stable enough for proper cali-
bration, the Model 820 will exit the
calibration mode without chang-
ing its calibration level. The “c”
indicates the instrument is cali-
brating.
The Model 820 will wait until the
reading is stable (indicator is
SsSsSs...., then adjust the offset for
the proper reading CcCcCc..... An
improper calibration offset (for
instance, something greater than
34.0 dB) may indicate that the cal-
ibration tone was shut off before
calibration was completed, or that
polarization was not properly set.
You may repeat the previous steps
or perform a Cal check.
Step 11
To Reset the Model 820 for re-calibration, press
U
and
R
.
The display will ask if you want to
“Reset ALL Data?” You do.
Step 12
Press
e
. Reset is complete and the instrument
will return to the calibration mode.
Step 13
To leave the calibration mode, press
c
.
