Tektronix 2715 Personal Computer Connections to Test Instrument

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 meterto the computer through GPIB
cables. Connect the instrument to be testedto 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.
Runningthe 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 measuringthe signal amplitude at one power divider output (refer to
Figure 5--22), then calculating the amplitude present at theinstrument’s RF Input
at the other power divider out put. The error in displayed flatness is then corrected
according to the calculated pow er available at the RF Input.
The CHAR program is designedto measure and record the difference in amplitude
between the power meter and the instrument’sRF Input.1
Ifa 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 meteris used, test setups
for characterizing the power divider output ports are shown in Figures5 --23 and
5--24. The power meter output of the power divider is characterizedby measuring
itsoutput amplitude, with a power meter,across the frequency range while the DUT
output,with min loss pad, is terminated with the 75 Ωtermination as in Figure 5--23.
The power meter and terminationconnections are then made as in Figure 5--24 to
determinethe response of the DUT output with the power meter output terminated.
The amplitude differencebetween the power meter and DUT outputs is then stored
in a data file for later use by the flat ness test.
To maintain a traceable calibration standard, this ch aracterization must be
performed whenever the power divi dero r any pads are replaced. Werecommen ded
dedicating these components to this test system to minimize characterization
requirements.
1Output of them in loss pad connected to powerdi vider device under test(DUT)
output.
Personal Computer
Connections to Test
Instrument