Philips PM3350A - Page 65

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4 APPLICATIONS
- TRIGGER DELAY SETTING
by pressing the TRIG DEL UP-DOWN key.
The TRIGger DELay setting offers PRE- and POST triggering.
In PRE triggering you can look BEFORE the trigger point. For example, if trigger
delay = -10 divisions, the trigger point is at the far RIGHT vertical graticule line.
What you see is then the signal BEFORE the trigger point.
This mode enables observation of events leading up to the trigger; e.g. to
pin-point the cause of a problem, for instance, a mains (line) transient.
The PM3350A/55/65A/75 all have a maximum PRE triggering of 10 divisions (max
TRIG DEL = -10 div.).
In trigger delay = 0 divisions the trigger point is at the LEFT vertical graticule
line.
In POST triggering you can look AFTER the trigger point For example, if trigger
delay = +10 divisions, the trigger point is one full screen LEFT of the screen
that you see.
This mode effectively stretches the memory capacity anc is for example very
useful wfhen measuring a certain line in a TV pattern.
The PM3350A/65A have the disposal of a POST triggering of max. 2500 divisions
(max. TRIG DEL = + 2500 div,). With the PM3355/75 the maximum POST
triggering is 5000 divisions (max, TRIG DEL = -i- 5000 div.).
NOTE: You can return to the default value of 0 divisions trigger delay by
pressing the TRIG DEL key and then the RESET key simultaneously.
4.2 use AS A DIGITAL STORAGE OSCILLOSCOPE