Power Meter Operation
Zeroing and Calibrating the Power Meter
2-8 Agilent E4419B User’s Guide
If you calibrate the sensor before zeroing it, the message changes to 
“Please Zero ChA” or “Please Zero ChB” depending on which channel the 
sensor is connected to.
The Zero/Cal Lockout facility can be enabled/disabled through either the 
System Inputs menu or the Zero Cal menu as follows:
Press , , ,    or .
Press ,  ,    or .
Calibrating the Power Meter
Calibration sets the gain of the power meter using a 50 MHz 1 mW 
calibrator as a traceable power reference. The power meter’s POWER REF 
output or a suitable external reference is used as the signal source for 
calibration. An essential part of calibrating is setting the correct reference 
calibration factor for the power sensor you are using. The Agilent 8480 
series power sensors require you to set the reference calibration factor. 
The Agilent E-series power sensors set the reference calibration factor 
automatically. During calibration the wait symbol is displayed. Offset, 
relative and duty cycle settings are ignored during calibration.
Note   During calibration the power meter automatically switches the 
power reference calibrator on (if it is not already on), then after 
calibration it switches it to the state it was in prior to the 
calibration.
Calibration Procedure Using Agilent E-Series Power 
Sensors
The following procedure describes how you calibrate the power meter with 
an Agilent E-series power sensor. Since the power meter automatically 
downloads the Agilent E-series power sensor’s calibration table there is no 
requirement to enter the reference calibration factor. The power meter 
identifies that an Agilent E-series power sensor is connected and will not 
allow you to select certain softkeys. The text on these softkeys appears 
grayed out.
More
Must Cal Off On
Zero
Cal
More
Must Cal Off On
HP4402.book  Page 8  Thursday, November 30, 2000  1:39 PM