Front Panel Operation
Publication 31470-001, Rev C, November 2, 2017
2-25
2.4.3.2
Zeroing Only
1.
For only zero one or both sensors, make sure both sensors are connected to the sensor inputs and that
neither sensor is connected to the Calibrator output. When zeroing a sensor, it is best to connect the sensor
to the device under test exactly as it will be used in measurement, and deactivate the RF output of that
device. Zeroing the sensor in place is the best way to counteract system noise which could significantly
affect low-level measurements.
2.
Turn off the source output before zeroing the sensor. The microwave source must output less than -74 dBm
of total noise power during RF Blanking for proper zeroing. The source signal power should be less than -90
dBm.
NOTE:
Sufficient time must be allowed for the module to reach thermal equilibrium with the source. This
could be up to 15 minutes for moderate initial temperature differences.
3.
Press
[CAL/ZERO]
. The meter will check that the sensors are installed and calibrated, then it will display a
menu to select Sensor A, B or both (All) to be zeroed. Select the sensor(s) to start the zeroing process, or
press
[Cancel]
to abort zeroing and return to the Main menu.
4.
The sensor should be zeroed just before recording final readings in the lower 15 dB of the power sensor’s
dynamic range.
5.
The sensor should remain connected to the signal source during zeroing. By turning off the source instead of
disconnecting the detector, the zeroing process automatically accounts for ground line voltages and
connector interface EMF.
NOTE:
Sufficient time must be allowed for the module to reach thermal equilibrium with the source. This
could be up to 15 minutes for moderate initial temperature differences.
2.4.3.3
Calibration & Zeroing (High Power Sensors with Removable Attenuators)
When using a Giga-tronics high power sensor with external attenuator, Giga-tronics power meters automatically
recognize the sensor type and compensates for the attenuation factor. However when performing the front
panel calibration, be sure to remove the attenuator before connecting to the calibrator port. During
measurement, there is no need to enter an offset factor to account for the attenuator loss. The sensor
frequency calibration factors automatically correct for the combined frequency response of the sensor and
attenuator. Because the sensor and attenuator are a matched set, the serial numbers of the sensor and
attenuator are identical. Do not use attenuators from other high power sensors.
1.
Remove the high power attenuator from the sensor.
2.
Connect the sensor to be calibrated from Channel A or B to the Calibrator Output (See Figure 2-14).
3.
Press the
[CAL/ZERO]
hardkey. The meter will automatically zero and calibrate the sensor.
4.
Reconnect the high power attenuator to the sensor.
NOTE:
There are alignment marks (arrows) on the sensor and attenuator. To reduce measurement
uncertainty, align the arrows when reconnecting the attenuator to the sensor.
Содержание 8650B Series
Страница 3: ...Series 8650B Universal Power Meters Publication 31470 001 Rev C November 2 2017 iii ...
Страница 18: ......
Страница 32: ......
Страница 78: ......
Страница 236: ......
Страница 244: ......
Страница 258: ......
Страница 263: ...Menu Structure Publication 31470 001 Rev C November 2 2017 D 3 Figure D 3 Modulation Sensor B Setup Menu Structure ...
Страница 265: ...Menu Stucture Publication 31470 001 Rev C November 2 2017 Page D 5 Figure D 4 Meter Setup Menu Structure ...
Страница 267: ...Publication 31470 001 Rev C November 2 2017 Last page of the document ...