HP 81200, Руководство пользователя, Страница: 88 / 240

Setting Global System Parameters How to Set the Clock Characteristics
88
HP 81200 Data Generator/Analyzer Platform User Guide, Revision 2.1
2
Enable the type of clock. External reference clocks can have 1, 2, 5, or
10 MHz.
3 If you have chosen an external reference or external source clock,
connect the clock.
4
Check the availability of the clock signal.
An external reference clock can be detected by clicking the Detect
button. The frequency of an external source clock can be measured by
clicking the Measure button.
If you have specified an external source clock and after you have
connected it and measured its frequency, you can use the clock multiplier
which is controlled from the lower right-hand corner of the window. The
clock multiplier enables you to multiply the applied clock frequency by any
integer factor between 1 and 256.
Only restriction: The frequency of the external source clock must exceed
1.302083 MHz.
How to Set the System Clock Parameters
You can specify the desired period or the desired frequency. Both is
equivalent.
Figure 28 Clock Parameters
To set the system clock parameters:
1 Accept or change the unit.
The Parameter Editor displays default units and has default vernier
steps. Both can be changed (see
“How to Change Units and/or Vernier
Steps” on page 69
).
2
Set the desired Frequency or Period .
If you need more than one clock frequency, it is recommended to enter
the basic frequency. This usually yields the highest resolution. Other
frequencies can be derived by multiplying or dividing the base frequency
by factors which are multiples of 2.
If you have typed a number, terminate your input with the Enter or
Return key. This updates the other field (Period or Frequency).