Faq - Tenma 72-6802 User Manual

F
AQ
The probe waveform is distorted.
You might need to compensate the probe. For details, see page26.
Note that frequency accuracy and duty factor are not specified for
the probe compensation waveform and therefore it should not be
used for reference purpose.
The trace line does not appear on the display.
Make sure that the trigger mode is in the AUTO mode. In the
NORMAL mode, the trace does not appear unless a trigger
condition occurs.
The alternate trigger (TRIG ALT switch) does not work.
Make sure that the ALT/CHOP switch is released (ALT position).
The TRIG ALT switch does not work in the CHOP mode.
The frequency counter in the LCD display does not work.
Make sure that the TRIG ALT switch is not pressed. The frequency
counter does not work in the alternate trigger mode.
The TV trigger does not work.
Make sure that the video synchronization signal is positive. The TV‐
V/TV‐H trigger works only when the synchronization signal is
negative.

FAQ

The input signal does not appear on the display.
Check the following settings.
• The coupling mode is not set at the GND mode, in which the
waveform does not appear on the display. See page22 for details.
•
The appropriate trigger source is selected. See page19 for details.
The oscilloscope accuracy does not match the specifications.
Make sure the oscilloscope is powered on for at least 30 minutes,
within +20°C – +30°C. This is necessary to stabilize the oscilloscope.
For more information, contact your local dealer, Tenma website
www.tenma.com., or MCM Electronics at www.mcmelectronics.com.
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72-6802 User Manual