Tektronix 1502C User Manual

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Appendix C: Operator Troubleshooting
1502C MTDR User Manual
C–5
At power on during initialization only.
The instrument changed the gain while adjusting the pulse to be two divisions
high and the change in the gain circuitry did not make the expected change in the
signal size.
Have the instrument repaired. If no other error messages occurred and the pulse
is present, distance measurements can be made. Do not make loss measurements
until the instrument has been repaired.
ERROR:
Acquisition Initialization
TYPE: 
Vertical Position failure
Pulse base off top of LCD
ERROR:
Acquisition Initialization
TYPE: 
Vertical Position failure
Pulse top below base of LCD
ERROR:
Acquisition Initialization
TYPE: 
Vertical Position failure
At power on during initialization only.
The instrument attempts to center the pulse before making it two divisions high.
These messages indicate that the waveform could not be properly placed on the
display. This usually means that the offset or gain circuitry on the Main board is
not working properly.
The instrument must be repaired. If it is possible to adjust the pulse vertically on
the display and no other error messages have been displayed, it might be possible
to make measurements. If the pulse is not two divisions high, do not make
measurements.
ERROR:
Acquisition Initialization
TYPE:
Leading edge of pulse not found
ERROR:
Acquisition Initialization
TYPE:
Top of 50 nsec ramp not found
This message can occur at power on initialization only. These are common error
messages because they are triggered by many kinds of failures and come from
one of the very first routines that the instrument executes. They are usually fatal
Occurrences:
Meanings:
Remedies:
Message:
Occurrences:
Meanings:
Remedies:
Message:
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