Technical data

4-15
Hardkey and Softkey Reference
LIST IF BW on OFF. enables or disables the ability to set independent IF bandwidths for each segment in a swept list
measurement.
LIST POWER on OFF. enables or disables the ability to set independent power levels for each segment in a swept list
measurement. When on, sets power range mode to manual to set a range for the power values. (The range can be
chosen using the PWR RANGE key.) The power values can be entered using the SEGMENT POWER key. If ports are
uncoupled, the power can be set independently for each port. When off, the SEGMENT POWER key will not function
and the power column in the swept list table will display asterisks. In this case, the power is set by the normal test port
power value.
LIST TYPE [STEPPED]. selects either stepped or swept list mode. For in-depth information on stepped list mode, refer to
“Stepped List Frequency Sweep (Hz)” on page 5-7“.
LIST VALUES. provides a tabular listing of all the measured data points and their current values, together with limit
information if it is turned on. At the same time, the screen menu is presented, to enable hard copy listings and access
new pages of the table. 30 lines of data are listed on each page, and the number of pages is determined by the number
of measurement points specified in the stimulus menu.
LN/MATCH 1. measures the TRL/LRM line or match standard for PORT 1.
LN/MATCH 2. measures the TRL/LRM line or match standard for PORT 2.
LOAD. defines the standard type as a load (termination). Loads are assigned a terminal impedance equal to the system
characteristic impedance Z0, but delay and loss offsets may still be added. If the load impedance is not Z0, use the
arbitrary impedance standard definition.
LOAD NO OFFSET. initiates measurement of a calibration standard load without offset.
LOAD OFFSET. initiates measurement of a calibration standard load with offset.
LOAD SEQ FROM DISK. presents the load sequence from disk menu. Select the desired sequence and the analyzer will
load it from disk.
Local. This key is used to return the analyzer to local (front panel) operation from remote (computer controlled)
operation. This key will also abort a test sequence or hardcopy print/plot. In this local mode, with a controller still
connected on GPIB, the analyzer can be operated manually (locally) from the front panel. This is the only front panel
key that is not disabled when the analyzer is remotely controlled over GPIB by a computer. The exception to this is
when local lockout is in effect: this is a remote command that disables the Local key, making it difficult to interfere
with the analyzer while it is under computer control.
LOG FREQ. activates a logarithmic frequency sweep mode. The source is stepped in logarithmic increments and the
data is displayed on a logarithmic graticule. This is slower than a continuous sweep with the same number of points,
and the entered sweep time may therefore be changed automatically. For frequency spans of less than two octaves, the
sweep type automatically reverts to linear sweep.
LOG MAG. displays the log magnitude format. This is the standard Cartesian format used to display magnitude-only
measurements of insertion loss, return loss, or absolute power in dB versus frequency.
LOG MKR. displays the logarithmic magnitude value and the phase of the active marker in Polar or Smith chart format.
Magnitude values are expressed in dB and phase in degrees. This is useful as a fast method of obtaining a reading of the
log magnitude value without changing to log magnitude format.
LOOP COUNTER. displays the current value of the loop counter and allows you to change the value of the loop counter.
Enter any number from 0 to 32767 and terminate with the x1 key. The default value of the counter is zero. This
command should be placed in a sequence that is separate from the measurement sequence. For this reason: the
measurement sequence containing a loop decision command must call itself in order to function. The LOOP
COUNTER command must be in a separate sequence or the counter value would always be reset to the initial value.
LOOP COUNTER (Sequence Filenaming). inserts the string “[LOOP]” into the file name.
LOSS. accepts a power loss value for a segment in the power meter cal power loss list. This value, for example, could be
the difference (in dB) between the coupled arm and through arm of a directional coupler.
LOSS/SENSR LISTS. presents the power loss/sensor lists menu. This menu performs two functions: 1) Corrects
coupled-arm power loss when a directional coupler is used to sample the RF output. 2) Allows calibration factor data to
be entered for one or two power sensors. Each function provides up to 12 separate frequency points, called segments,
at which the user may enter a different power loss or calibration factor. The instrument interpolates between the
selected points. Two power sensor lists are provided because no single power sensor can cover the frequency range of
the analyzer.