Agilent Technologies 1141A, Руководство пользователя и сервисное руководство

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Operating the Probe 1
Remote Operation
1141A and 1142A User’s Guide 23
CAUTION
If you measure a node having a high dc potential, the blocking capacitors in the ac
adapter will charge to that potential. After making such measurements, discharge
the capacitors by grounding both inputs of the ac adapter. This will prevent damage
by a high voltage discharge into sensitive circuitry when the next measurement is
made.
To use ac coupling:
1
Attach the ac coupling adapter to the input of the probe or the
input of the attenuator adapter.
2 On the 1142A, press Local and Zero offset .
Remote Operation
For automatic test applications, the coupling and offset functions
provided by the 1142A Probe Control and Power Module can be
remotely controlled through the rear- panel standard 9- pin female D
sub- miniature connector. The following table gives the connections.
NOTE
To minimize dc offset errors and potential noise coupling, electrically isolate all
connections between the Remote Input connector and the controlling system.
Function Select
The easiest way to control the function select lines is contact
closures between the lines and Digital common (pin 2) of the
remote input connector. (TTL compatible control signals can be
used; but to avoid problems with ground loops, they must be
electrically isolated.) The following truth table shows the functions
provided by the function select lines. For the Remote Inputs, “0”
represents a closure and “1” represents an open circuit.
Table 3 Remote Input Connections
Pin Function Pin Function Connector
1 Function Select 1 (A1R) 6 Function Select 0 (A0R)
2 Digital common 7 N.C.
3 N.C. 8 N.C.
4 External offset common 9 External offset
5 Shield