Example 4C: Power Meter Calibration - Agilent Technologies 8719ET Programmer's Manual

Programming Examples
Measurement Process Synchronization Examples

Example 4C: Power Meter Calibration

NOTE This example program will not work with HP BASIC for Windows.
For increased accuracy of the analyzer's PORT 1-output power, a power meter calibration
is available. This measurement-accuracy enhancement technique is described in your
analyzer's user's guide. The example described will perform the sample and sweep
calibration under GPIB remote control.
The power meter is usually connected to PORT 1 for the forward measurements. Its
address must be set correctly and it must be connected to the GPIB. The power meter
address can be set by pressing: and
SET ADDRESSES ADDRESS P MTR/GPIB
Local
using the and keys or the numeric key pad to complete the process. The
appropriate command must be selected for the model number of power meter being used.
Press until the model being used is displayed between the brackets.
POWER MTR: [ ]
The correction factors for the power sensor are entered into the analyzer. All of these steps
are explained in your analyzer's user's guide.
The number of readings-per-point must also be selected before starting. The number of
points directly affects the measurement time of the calibration sequence. The power meter
must be triggered and read by the analyzer for each trace point. Typically, two
readings-per-point is considered appropriate. More than two readings-per-point could lead
to unacceptable processing time.
To control a power meter calibration via GPIB, the analyzer must be set to pass-control
mode. The analyzer must step to the next point in the sweep and read the power present at
the power meter sensor. For this operation to take place, the system controller must set up
the measurement and then pass control to the analyzer to read each data point in the
sweep. After reading the data point from the power meter, the analyzer passes control back
to the system controller. The analyzer then sets up to measure the next point and again
requests control from the system controller. This process continues until the analyzer
signals that the entire sweep has been measured point-by-point.
The following is an outline of the program's processing sequence:
• An I/O path is assigned for the analyzer.
• The system is initialized.
• The number of points in the trace is set.
• The number of readings-per-point is set.
• The frequency span is set.
Chapter 7 7-75