Filter
Top Products
Adjustment Procedures
2715 Spectrum Analyzer Service Manual
5-57
Use the following procedure to connect the PC to the instrument.
1. Connect the signal generator and power meter to the computer through GPIB
cables. Connect the instrument to be tested to the computer through a GPIB
or RS--232 cable. See the 2714 & 2715 Programmer Manual for a descrip-
tion of the RS--232 cable requirements.
2. Apply power to the instrument and test equipment, then allow a warmup of
at least one hour.
3. If applicable, set the GPIB address of the 2715 to 1.
Running the Test Equipment Characterization Program (CHAR). The flatness test uses
a power divider and power meter to compensate for flatness variations in the
generator, and for losses in the test system cabling. The flatness test performs this
correction by measuring the signal amplitude at one power divider output (refer to
Figure 5--22), then calculating the amplitude present at the instrument’s RF Input
at the other power divider output. The error in displayed flatness is then corrected
according to the calculated power available at the RF Input.
The CHAR program is designed to measure and record the difference in amplitude
between the power meter and the instrument’s RF Input.
1
If a dual channel meter is used, then both outputs are characterized at the same time
using the setup in Figure 5--22. If a single channel power meter is used, test setups
for characterizing the power divider output ports are shown in Figures 5--23 and
5--24. The power meter output of the power divider is characterized by measuring
its output amplitude, with a power meter, across the frequency range while the DUT
output, with min loss pad, is terminated with the75 Ω termination as in Figure 5--23.
The power meter and termination connections are then made as in Figure 5--24 to
determine the response of the DUT output with the power meter output terminated.
The amplitude difference between the power meter and DUT outputs is then stored
in a data file for later use by the flatness test.
To maintain a traceable calibration standard, this characterization must be
performed whenever the power divider or any pads are replaced. We recommended
dedicating these components to this test system to minimize characterization
requirements.
1
Output of the m in loss pad connected to power divider device under test (DUT)
output.
Personal Computer
Connections to Test
Instrument