Keysight Technologies L4490A, User Manual

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Keysight L4490A/L4491A User’s Guide 37
Hardware Configuration
PC to L4490A/L4491A.
When connecting the PC directly to the
L4490A/L4491A, the LAN cross-over cable provided with the L4490A/L4491A is
used. If your PC supports Auto-MDIX or contains a LAN card with Gigabit data
transfer rates, the cross-over cable is not required. A standard LAN cable may be
used instead.
For network configurations (private or site) that include a LAN switch or router
between the PC and L4490A/L4491A, standard LAN cables are used. Do not use
the cross-over cable.
L4490A/L4491A to 34945EXT.
The L4490A/L4491A controller box is
connected directly to the master 34945EXT and also to the second (slave)
34945EXT if installed in the L4491A (Option 002). +24V is supplied through this
connection. An external supply can also be used with the 34945EXTs for
applications requiring increased switching capacity.
34945EXT to 34945EXT.
L4491A Option 002 adds a second (slave) 34945EXT
module. The second 34945EXT comes connected within the L4491A chassis to
the master 34945EXT using a standard LAN cable between the master’s
Expansion Bus Port 1 and Expansion Port 2 of the second EXT module. (The ports
of all slave 34945EXTs are interchangeable.) Up to eight 34945EXT modules
(including the master) can be used per L4490A or L4491A.
34945EXT to External Power Supplies.
All slave 34945EXT modules external
to the L4490A or L4491A chassis must use an external power supply or supplies.
Note that the supply voltage (+24V, +12V, +5V) applies to all distribution board
banks on the 34945EXT.
The 34945EXT Module
Microwave switches and attenuators are connected to the L4490A/L4491A
configuration through distribution boards (Y1150A - Y1155A) installed on the
34945EXT module (Figure 2-2).
The 34945EXT is divided into four banks organized by channel number. Any
distribution board may be installed in any bank, and multiple distribution boards
of the same type may be installed on the same 34945EXT module. Distribution
boards can be installed or removed with the L4490A/L4491A turned on;
however, the channel drive source (Figures 4-2, 4-3) must be off.
The “I/O ACCESS” LED on the EXT module indicates communication sequences
between the L4490A/L4491A controller box and the 34945EXT.
The Y1156A Verification Board
The optional Y1156A Verification board (not shown) is used to verify the signal
path from the PC to banks 1-4 on the 34945EXT. Verification of the path is
recommended before connecting switches or attenuators to the distribution
boards, or if a problem is suspected. See Chapter 4 for more information.