Agilent Technologies 4294A, Programming Manual

Page: 58 / 518

58 Chapter 4
Preparing For Accurate Measurement
User Calibration
User Calibration
Selecting either 7mm or PROBE while setting the adapter allows you to use the user
calibration functions. To turn the user calibration functions on or off, use the command
given below. If no user calibration coefficients have been retained, the user calibration
functions cannot be turned on.
• “CALST” on page 276
To measure open data, short data and load data for calculating the user calibration
coefficients, use the command given below.
• “CAL{A|B|C}” on page 274
NOTE
User calibration data and fixture compensation data are measured either at fixed points
preset by the Agilent 4294A (fixed measurement points) or at sweep measurement points
set at the time of command execution (user measurement points). In the former case, the
compensation coefficient at a sweep measurement point is obtained by interpolation. To
select points for measuring data, use the “CALP” command on page 275.
To set standard values to be used in measuring these data, use the commands given below.
• “DCALOPEN{G|C}” on page 288
• “DCALSHOR{R|L}” on page 289
• “DCALLOAD{R|L}” on page 287
After measuring individual data, execute the command given below to calculate the user
calibration coefficient and to store it in volatile memory (RAM).
• “CALDON” on page 274
NOTE
To calculate the user calibration coefficient, all of the open data, short data and load data
are required. If you execute this command before measurement of the data is fully
completed, an error occurs and the command is ignored.
To suspend the above process, execute the command given below.
• “CALQUI” on page 275