Getting The Best Speed Performance; Speed; Trigger Mode - HP E4418B Programming Manual

Power Meter Remote Operation

Getting the Best Speed Performance

Getting the Best Speed Performance
This section discusses the factors that influence the speed of operation
(number of readings/sec) of an HP E4418B/E4419B power meter.
The following factors are those which have the greatest effect upon
measurement speed (in no particular order):
• The selected speed i.e. 20, 40 or 200 readings/sec.
• The trigger mode (for example, free run, trigger with delay etc.).
• The output format i.e. ASCii or REAL.
• The units used for the measurement.
• The command used to take a measurement.
In addition, in 200 reading/sec mode there are other influences which are
described in "200 Readings/Sec", on page 1-68.
The following paragraphs give a brief description of the above factors and
how they are controlled from SCPI.

Speed

There are three possible speed settings 20, 40 and 200 readings/sec. These
are set using the SENSe:SPEed command and can be applied to each
channel independently (HP E4419B only). The speed setting controls the
cycle time of the measurement i.e., 50ms, 25ms and 5ms respectively.
In 20 and 40 readings/sec mode, full instrument functionality is available;
200 readings/sec is available only for E-series sensors and averaging,
offsets, limits, and ratio/difference math functions are disabled.
Refer to "Specifications" in chapter 5 of the User's Guide to see the
influence of these speed settings on the accuracy and noise performance of
the power meter.

Trigger Mode

The power meter has a very flexible triggering system. For simplicity, it
can be described as having three modes:
1-66 HP E4418B/E4419B Programming Guide