GW Instek GRS-6000A Series - Manual (Page 16)

GRS-6052A/6032A OSCILLOSCOPE
USER MANUAL
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(32) TV—Pushbutton for video sync signal selection
Separate the video sync signal from the composite waveform and direct it to
the triggering circuit. The horizontal or vertical sync signals are selected by
TV pushbutton. The current setting is displayed in the readout under item
(source, video polarity, “TVV or TVH”). Each time when the pushbutton is
pressed, the video sync signal is displayed in the sequences as follows:
TV-V—TV-H—OFF—TV-V
TV-V
Start the main trace at the beginning of a video signal field. The polarity
must match the composite sync polarity (i.e, “ ” for negative sync) to
obtain TV field triggering on the vertical sync pulse.
TV-H
Start the main trace at the beginning of a video signal line. The polarity
must match the composite sync polarity to obtain TV line triggering on the
horizontal sync pulse.
(33) SLOPE—Pushbutton for the triggering slope.
Briefly pressing the pushbutton to select the slope of the signal which is
used for triggering the time base generator. Each time when the pushbutton
is briefly pressed, the slope direction will switch from falling edge to rising
edge, and vice versa.
The current setting is displayed in the readout under item “source, SLOPE,
coupling”.
If in the TV trigger mode, it is synchronized only when the sync signal is
negative. A “ ” symbol is displayed in the readout.
GRS-6052A/6032A OSCILLOSCOPE
USER MANUAL
⎯ ⎯
27
(34) COUPLING—
Pressing the pushbutton to select the trigger coupling. The actual setting is
indicated by the readout (source, slope “COUPLING”).
Each time when the COUPLING pushbutton is pressed the trigger coupling
changes in the sequence:
AC—HFR—LFR—AC
AC
Attenuates trigger signal frequency components below 20Hz and blocks the
DC component of the signal.
AC coupling is useful for triggering on AC waveforms that have a large DC
offset.
HFR (High Frequency Reject)
Attenuates high-frequency triggering signal components above 50kHz. HFR
coupling is useful for providing a stable display of low-frequency
components of complex waveforms and eliminates high-frequency
interference from the trigger signal.
LFR (Low Frequency Reject)
Attenuates low-frequency triggering signal components below 30kHz and
blocks the DC component of the trigger signal.
LFR coupling is useful for producing stable triggering on the high-
frequency components of complex waveforms and rejecting low-frequency
interference or power supply hum from the trigger signal.
(35) TRIGGER LEVEL—Control knob with TRG LED
Turning the control knob causes a different trigger input setting (voltage),
and set to a suitable position for the starting of triggered sweep of the
waveform. When rotate clockwise the control knob, the trigger point moves
toward the positive peak of the trigger signal and rotate it counterclockwise
to move the trigger point toward the negative peak of the trigger signal.