Philips PM3350A - Page 47

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4 APPLICATIONS
- Trigger level
by adjusting the TRIG LEVEL rotary knob.
For repetitive signals, a stable, Jitter-free display will only be obtained if each
time-base sweep Is triggered at precisely the same point on the signal waveform.
The trigger level is adjusted with the TRIG LEVEL rotary knob.
- Trigger coupling
by the trig COUPL key.
Six modes can be selected for trigger coupling:
P-P Peak-to-peak triggering gives automatic ranging of the TRIG
LEVEL knob, the ranging being determined by the peak-to-peak
value of the signal. DC signals are rejected.
DC DC triggering; the full bandwidth of the trigger channel is
available, while the level range of the rotary knob is more than
± 3 divisions.
In this mode, the trigger level can also be shown with the LEVEL
VIEW key. By pressing the LEVEL VIEW key, the trigger level
will be shown as a DC voltage, related to the vertical mid of the
oscilloscope screen (vertical mid = 0 volt). After adjusting the
TRIG LEVEL rotary knob press the LEVEL VIEW knob again to
return to the original screen.
TVF tv frame triggering allows triggering at the slow TV frame (field)
synchronisation pulses; the TRIG LEVEL rotary knob is
inoperative.
TVL tv line triggering allows triggering at the fast TV line
synchronisation pulses; the TRIG LEVEL rotary knob is
inoperative.
LF In this mode the signal used for triggering is first passed
through a low-pass filter with a cut-off frequency of 50 kHz.
All components with high frequencies are rejected.
HF In this mode the signal used for triggering is first passed
through a high-pass filter with a cut-off frequency of 50 kHz.
All components with low frequencies are rejected.
4.1 USE AS AN ANALOG OSCILLOSCOPE