21
The channel dependencies indicated on Lines 6 and 7 are updated automatically by
the P400 and appear on this menu for convenience. Dependencies are not alterable
by the user on this page, but they are set by the user on menu pages for Channels A
through D. If a channel is in delay/width mode, its fall is shown as WD.
5.7
Channel A through D Menus
- 4. 30 t o +11. 80
- 5. 00 t o + 4. 10
+
-
CHANNEL:
A
ON
POLARI TY
+
VH
+ 4. 00
MODE
/
VL
+ 0. 00
A RI SE REL TO:
T0
+000. 000 100 000 000
A FALL REL TO:
T0
+000. 000 200 000 000
1
2
3
4
5
6
7
- 999. 999 999 999 999 t o
+999. 999 999 999 999
Set by user
Set by P400
A
B
C
D
ON
OFF
- 999. 999 999 999 999 t o
+999. 999 999 999 999
D/ W
/
DELAY
RI SE
WI DTH
FALL
T0 A A B B C C D D
T0 A A B B C C D D
Figure 9. Channel A through D Menus
There are four channel menus. A typical menu, Channel A, is shown. Press the
appropriate button on the front panel to select the desired channel menu.
VH is the selected channel’s output’s high level, and VL is the low level.
If polarity is set as positive and the channel is quiescent (non-triggered), output
voltage level is VL, and the active pulse level is VH. If polarity is set to negative, the
output is inverted, i.e., VH is the quiescent state, and VL is the active output level. If a
channel is set to OFF, it remains at its quiescent level.
Note that VH and VL levels are as measured into a high-impedance load. If external
50
Ω
termination is used, output levels will be one-half those shown. For example, to
produce ECL levels with an external 50
Ω
termination to ground, set VH to –1.6 V and
VL to –4.0 V. The P400 output should not swing more than 5 volts while driving high-
impedance loads (see Section 6).
When a channel mode is selected as D/W, the output pulse is characterized by by an
initial delay followed by a width. In this mode, Lines 4 and 6 will show “delay” and
