Philips PM3350A - Page 43

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4 APPLICATIONS
4.1.3. TRIGGER MODE
In trigger mode the following selections can be made:
- Time-base trigger mode
by using the TB TRIG MODE key.
The time base can operate in three modes:
AUTO the horizontal sweep normally starts when a trigger occurs. II no
trigger is detected within 100 ms after the last sweep then a
sweep start automatically occurs. This means a trace is always
visible on the display.
TRIG horizontal sweep will only start on a trigger pulse derived from
the selected trigger source.
SINGLE horizontal sweep runs only once alter it is armed by the RESET
key and the receipt of a trigger pulse derived from the selected
trigger source.The mode is very useful to capture single events.
If the display mode is ALT {alternate), a special selection of single shot can be
made in the application preselect menu (APPL),
- enter the APPL menu by pressing MENU and keep it pressed. Then press
AUTO SET,
- select the CRT softkey APPL,
- select the CRT softkey SNGL_SHOT,
- select the CRT softkey FIRST or MULTI
FIRST = single shot Is always done on channel A (provided this channel
is active).
MULTI = single shot alternates between A, B and ADD (provided these
functions are active).
Leave the application preselect menu again by pressing the AUTO SET key.
The chosen SNGL_SHOT setting remains selected after leaving the application
preselect menu.
4.1 USS AS AN ANALOG OSCILLOSCOPE