Specifications

When developing test system
programs, you can open up a
Web Browser to the 34980A/
L4445A, and you can observe
switches closing and configura-
tions changing. The Web Server
can be set to capture every
command/response coming from
any interface: Web Browser, USB
(34980A only), GPIB, or LAN.
The Web Browser is included
in this list because it actually
sends programming commands
(SCPI) to cause changes to the
instrument. This helps with
understanding the sequence of
your test program. That feature
is a Learning Aid. Every time
you interactively close/open
any switch or program any
module to any setting with Web
Browser, the logging feature
actually shows what SCPI
commands were used. You can
cut and paste those commands
into your test program. You
literally don’t need a reference
manual to understand which
commands are needed to set
up a particular module!
Once your test system is run-
ning, you can passively monitor
any channel from up to six
Web Browsers. Bringing up a
Web Browser to the 34980A/
L4445A is always passive when
you connect. Unlike some ven-
dors’ instruments, the 34980A/
L4445A Web Server does not
reset or interfere with any
configuration when it connects.
You have to purposely interfere
with modules. You can even
configure and work with mod-
ules that are not currently
being used by the test system
program!
Of particular importance in
RF/Microwave test systems is
creating switch paths and
sequences that completely set
up different measurements.
The 34980A/L4445A provides
a Switch Sequencer for that
purpose, and that is the topic
of the next section.
Switch Executives vs. Agilent
34980A/L4445A Switch Sequencer
When setting up a test system,
it is important to make sure
that measurement instruments,
sources, DUT test points, etc.
all switch at the right time and
in the right sequence. A matrix
switch allows any point to con-
nect to any other point, so it is
possible to connect two signal
sources together. This must be
avoided.
Some measurement setups
are fairly complex and require
the correct sequence and path
through the switching system.
Some switches operate quicker
than others. Some sources
need settling time after being
connected to a load. In short, a
switch path can include a lot of
switches and require a proper
sequencing of those switches.
That can be a challenge for a
programmer.
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Digital Input
Position Indicators
Continuous Mode
Single Coil Channel
Pulse drive
Open collector
Pulse Mode
Paired Channels
No position feedback