Agilent Technologies E4418B, User Manual

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Power Meter Operation 2
E4418B Power Meter User’s Guide 99
Serial Interface
Four tests are available for the serial interface: UART configuration, local
loop back, RS232 loop back and RS422 loop back. Both the RS232 and
RS422 loop back tests require a specially wired connector - refer to the
Agilent E4418B/E4419B Service Guide .
•
UART Configuration - confirms that the baud rate, stop bits and parity
settings are correctly configured on the UART.
• Local Loop Back - Tx and Rx on the UART are internally connected
and a test message is sent to confirm correct operation.
• RS232/RS422 Loop Back - A message is sent via the UART and
transceivers using an external loop back connector (refer to the
Agilent
E4418B/E4419B Service Guide ).
Option 001 Battery
This test checks that the capacity of the Option 001 battery has not
decayed below 70% of its original value. The test is only performed on
power meters fitted with Option 001.
Calibrator
The reference calibrator is turned on (indicated by the POWER REF LED)
and measured internally. A pass or fail result is returned.
Keyboard (Front Panel only)
The power meter enters a mode where you are invited to press any key.
When a key is pressed, its name appears on the screen. You can check
that the power meter is displaying the expected name when the relevant
key is pressed. This is a check that the power meter is receiving the
correct keyboard signal. Pressing the same key twice sequentially exits this
mode and returns you to a display that lists all the keys that were not
entered. If the test is exited without all the keys being pressed, a list is
displayed showing all the keys which were not selected.
Display
Three tests are available for the display: the display assembly, display
RAM and bitmap display.