Tektronix 2715, User Manual

Page: 310 / 360

Appendix C: System Messages
C–8
2715 User Manual
MARKER WOULD OVERWRITE NOISE VALUE
Enabling the marker would overwrite the saved Carrier-to-Noise or
Normalized Noise value. Markers cannot be placed on a display saved with
Carrier-to-Noise or Noise Norm’d modes enabled.
MUST BE IN DELTA MARKER MODE
Turn on Delta Markers to obtain desired function.
NO CSO BEATS ARE DEFINED
This message appears when a continuous CSO test terminates because no
beats were specified in the CSO setup menu.
NO LISTENER
A screen plot front-panel operation was attempted to the GPIB port but no
listen addressed devices were available. Place a listen-addressed device on
the bus and reselect the operation.
NO MODULATION ON SIGNAL
Occurs in zero span when CTR MEAS is attempted and there is no constant
frequency modulation on the carrier.
NO QUIET VIDEO LINES FOUND
Quiet lines are retrace lines where no modulation is present. The Carrier-to-
Noise and Composite Second Order tests use quiet lines to take in-service
measurements.The 2715 was unable to automatically find quiet lines to use
for the tests.
NO REFERENCE DEFINED
A function was invoked which requires a valid current reference, but no such
reference exists.
NO SIGNAL (NORMALIZATIONS)
Perform normalizations again. Contact your local Tektronix service center or
representative if message persists.
NO SIGNAL FOUND ABOVE THRESHOLD
There is no displayed signal exceeding the marker threshold value. Thresh-
old can be reset using the MKR/FREQ menu.
NO SIGNAL AT CENTER OF DISPLAY
Firmware/hardware error. Contact service center if message displays
repeatedly.
NO SIGNAL AT COUNTER INPUT
Perform normalizations again. Contact your local Tektronix service center or
representative if message persists.