To zero the sensor without calibration, press the Cal/Zero front panel key
and the Zero soft key, then select the appropriate sensor.
Note that if only one sensor is connected, the A-B selection is not dis
-
played and the zeroing process begins immediately.
The message changes to SENSOR x ZERO . . . . On successful comple
-
tion of the zeroing operation, the buzzer sounds. Sensor calibration should
be performed next.
If the sensor fails the zeroing operation, the message SENSOR x ZERO
fail nxnnn is displayed. The hexadecimal error code '
nxnnn
' indicates the
detailed reason for the failure, which is usually due to excessive RF noise.
The sensors can also be zeroed using the GPIB ZERO command (see
Chapter 6, “GPIB Operation”).
5-4
SENSOR CALIBRATION
Referencing power sensors to the ML2430A Series 50 MHz, 0.0 dBm cali-
brator is recommended. Sensors should be zeroed before being cali-
brated, either as a separate operation (Section 5-3) or in conjunction with
calibration (Section 5-5).
To reference the sensor, connect the sensor to the ML2430A Series 50
MHz, 0.0 dBm reference output connector labeled CALIBRATOR or an
-
other 50 MHz, 0.0 dBm reference.
When the sensor is first attached, the message SENSOR x NOT ZE
-
ROED (where
x
= A or B as appropriate) is displayed. Perform the sensor
zeroing procedure described in Section 5-3 to zero the sensor.
To calibrate the sensor after zeroing, press the Cal/Zero front panel key
and the Cal 0 dBm soft key, then select the appropriate sensor.
Note that if only one sensor is connected, the A-B selection is not dis
-
played and the zeroing process begins immediately.
On successful completion of the calibration operation, the buzzer sounds.
If the sensor fails the calibration operation, the message SENSOR x CAL
0 dBm invalid is displayed.
5-2 ML2430A OM
SENSOR CALIBRATION PROCEDURES
NOTE
When a Universal
Power Sensor with op
-
tion 1 fitted is changed
from T-RMS mode to
F-CW mode the user
should perform a new
zero/cal
ML2430A
Cal/Zero Zero Sensor A
Sensor B
Figure 5-1. Sensor Zeroing Key Sequence
ML2430A
Cal/Zero 0 dBm Sensor A
Sensor B
Figure 5-2. Sensor Calibration Key Sequence
