Agilent Technologies E4419B User Manual page 127

• UART Configuration - confirms that the baud rate, stop bits and parity
• Local Loop Back - Tx and Rx on the UART are internally connected and a
• RS232/RS422 Loop Back - A message is sent via the UART and transceivers
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.
A read or write is performed on the display RAM. If the value which is written
is read back correctly, a pass is recorded, otherwise a fail is recorded.
The liquid crystal display/light emitting diode (LCD/LED) control circuits are
tested by making separate voltage measurements via the multiplexer and
digital signal processor. If the expected voltages are measured, a pass is
E4419B Power Meter User's Guide
settings are correctly configured on the UART.
test message is sent to confirm correct operation.
using an external loop back connector (refer to the Agilent E4418B/E4419B
Service Guide).
Power Meter Operation 2
105