Keysight 34959A, Руководство пользователя

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Keysight 34959A User’s Guide 21
Installing a Custom PC Board
The remaining space in the breadboard module is available for installing custom
circuitry. Fifteen 3.18 mm (0.125”) diameter holes, countersunk on the bottom of
the sheet metal base, are provided for mounting the PC board to the base. The
maximum allowable height of the board and attached components above the
base, including spacers, is 23 mm. Assuming a PC board thickness of 1.6 mm, you
should use 5.1 mm long spacers and M3x0.5mm thread flathead screws. The
figure on page 25 provides the dimensions of the largest PC board which will fit
the breadboard module, the locations of the countersunk mounting holes, and
their location relative to the ribbon cable headers and Dsub ports.
If you utilize a PC board with the maximum allowable dimensions, it may be
necessary to first remove the Keysight-supplied PC board (34980A backplane
interface with ribbon cable headers), install the custom board by inserting the
Dsub connectors into the ports provided, secure the custom board, and then
reinstall the Keysight-supplied PC board. When the module assembly is complete,
replace the sheet metal cover and install the module in an available slot within the
34980A mainframe.
Extending the Breadboard Connections During Development
During development of your custom circuitry, you may need to work with your PC
board on a test bench, outside the confines of the breadboard module. This
should be done by using ribbon cable extenders and extra length of Analog Bus
connection wire. Once your final PC board configuration is achieved, these leads
should be shortened to allow fixed installation of the PC board inside the module.
Spacing and Insulation Requirements for High Voltage Applications
If your planned use of the 34959A breadboard module will involve the application
of high voltages (>30V
rms
AC or >60V DC), refer to appropriate electrical
standards for high-voltage circuit spacing and wire insulation requirements.
CAUTION
Use of the Y1132A Service Extender from the 34980A mainframe to the
breadboard module is not recommended, because the Service Extender is
not rated for the 300V potentials available on the breadboard’s Analog Bus
connectors.