User Manual LW120
ernal references. The LW120 has two reference options: Standard
00ppm and TCXO – 1ppm. An external reference input is provided
applications requiring better accuracy and stability. Click on th
ctivate the external reference input.
By selecting an external reference you are disabling the
internal reference circuit. If you do not have a 10 MHz
reference connected to the instrument, the output will
generate erroneous frequencie
Sequence Advance
ext
– 1
for
e
Internal button to select the Internal reference, or the External button
to a
WARNING
for the sequence generator. Advance options are: Auto, Stepped,
Single and Mixed. Refer to the LW120 manual to find out more when
and how to use these advance modes. You should be careful while
selecting modes because it is possible to cause settings conflict, for
example, if you select the Single option and you forgot to change your
trigger mode to Triggered.
The External Internal switch selects the trigger advance source.
External - enables the TRIG IN connector at the back of
trigger generator to the trigger advance circuit.
Besides the grouped controls, there are five other buttons available on
the Arbitrary & Sequence Panel. These buttons provide access to
(from top to bottom) W
Panel from the screen. The Wave Composer will be discussed
separately in this chapter. The Segment and Sequence Tables are
described below.
If you want to learn more about segment control, you should refer to
section 3 o
w
b
rument with this option.
ing such a long memory to store waveforms does not necessari
an that you have to use the entire memory every time yo
nload a waveform. On the contrary, the LW120 allow
mentation of the memory so that up to 4096 smaller waveform
d it with waveform data, define the next and load with data, then
s.
The Sequence Advance group provides control over advance modes
the
instrument. Internal – disables the trigger input and routes an internal
ave Composer, Sequence Table, Segment
Table, Main Panel. The last button removes the Arbitrary & Sequence
Using the Segment
Table
f this manual. In general, the LW120 can generate arbitrary
aveforms but before it can generate anything, the waveforms have to
e downloaded to the instrument from a host computer. The
waveforms are downloaded as coordinates and are stored in the
LW120 is a place designated as “waveform memory”. The waveform
memory has a finite size of 1Meg, or 4Meg if you purchased the
inst
Hav
ly
me
u
dow
s
seg
s
could be stored in the waveform memory. There are two ways to
divide the waveform memory to segments: Define a segment and
loa
ArbExplorer 5-13