Units; Command Used; Fast Mode - Keysight Technologies EPM-P Series Programming Manual

1 Power Meter Remote Operation

Units

The power meter can output results in either linear or log units. The internal units
are linear and therefore optimal performance will be achieved when the results
output are also in linear units (since the overhead of performing a log function is
removed).

Command used

In Free Run mode, FETCh? must be used to return a result.
In other trigger modes, there are a number of commands which can be used, for
example, MEASure?, READ?, FETCh? Note that the MEAS? and READ? commands
are compound commands - they perform a combination of other lower level
commands. In general, the best speed performance is achieved using the low
level commands directly.
Trigger count
To get the fastest measurement speed the a TRIG:COUNT must be set to return
multiple measurements for each FETCh command. For average only
measurements a count of 4 is required but 10 is recommended. In normal mode
(peak measurements) a count of 50 is required to attain 1000 readings per
second.

Fast mode

In the highest speed setting, the limiting factor tends to be the speed of the
controller being used to retrieve results from the power meter, and to a certain
extent, the volume of GPIB traffic. The latter can be reduced using the FORMat
REAL command to return results in binary format. The former is a combination of
two factors:
– the hardware platform being used.
– the programming environment being used.
94 Keysight EPM-P Series Programming Guide