HP HP 8712ES, Руководство пользователя, Страница: 67 / 507

ES User’s Guide 3-15
Making Measurements
Using the BEGIN Key to Make Measurements
BEGIN Key Overview
The key sets up a generic instrument state for the testing of
various types of devices.
The key has two different behaviors, depending on whether
you are selecting a new device type, or a new measurement type.
Selecting a New
Device When you use the key to select a new device type and
measurement, the analyzer does the following:
• presets the analyzer (except for external reference parameters, and
trigger mode)
• takes a sweep
• autoscales the measurement
• places a marker on the maximum or minimum point (depending on
the type of measurement)
• makes the marker active
• modifies the sweep time (Option 100 only)
See Table 3-1, “Measurement Configurations from the BEGIN Key,” for a
table of parameters for each measurement type.
Selecting a New
Measurement Once you have selected your device, you can use the softkeys to select the
measurement you wish to make. When you select a new measurement, a
preset is not done. It is assumed that you are simply changing
measurement types and that you may have already changed some of the
analyzer's parameters (such as frequency, power, etc.) for your DUT. In
this situation, you would probably not want these parameters changed
for subsequent measurements.
NOTE
If the new measurement selected is a broadband measurement such as
power, or conversion loss, the start frequency is limited to at least
10 MHz. Therefore, if your customized setup contains a start frequency
below 10 MHz and you choose power, or conversion loss, the start
frequency will be changed to 10 MHz. The stop frequency will remain
unchanged, unless it was set to below 10 MHz.
The BEGIN Key
and Measurement
Channels The key is designed to work when measurement channel 1 is
active. However, it does change the mode of measurement channel 2 as
well.
BEGIN
BEGIN
BEGIN
BEGIN