19
5.5
Trigger Menu
I NTERNAL
E
EXTERNAL-
MANUAL
LI NE
REMOTE
- 2. 40 t o + 4. 60
50
Hi Z
TRI GGER
I NTERNAL
TERM
50
LEVEL+
1. 00
BURST OFF I NT TRI G:
FRQ
00 001 000. 00
Hz
PER
000. 001 000 0
s
BURST REP PERI OD:
0 000 000. 002 000
s
BURST PULSES N
1
OF TRI GGERS M
2
BURST COUNTER
0
1
2
3
4
5
6
7
8
9
10
1 t o M - 1
00 000 000. 01 t o
10 000 000. 00
Set by user
Set by P400
N + 1 t o 65535
0 t o OF TRI GGERS - 1
ON
OFF
Figure 7. Trigger Menu
Press the TRIG key to display the Trigger menu. Place the cursor on Line 1 of the
display, and use the spinner knob to select the trigger source. If spurious triggers
might constitute a hazard, press the STOP button before altering any trigger menu
items, and press START only after all desired trigger setups have been edited.
When internal trigger mode is selected, the P400 is triggered by the internal DDS
generator at the rate shown in Line 4, FRQ. Line 5, PER, is set by the P400 to
display the period corresponding to the trigger frequency in Line 4.
When external mode is selected, the P400 accepts a trigger applied to the trigger
connector on the front panel. E responds to a rising edge, and
EXTERNAL- triggers on a falling edge. The trigger level can only be adjusted when
using EXTERNAL trigger mode.
The TERM item on Line 2 allows the external trigger input to be selected as high-
impedance (1 Megohm) or as a 50-ohm termination.
When MANUAL triggering is selected, press the START button to trigger the P400. If
the START button is held down, the P400 will continue to trigger at about 3 Hz.
