Tektronix 7834

DETAILED OPERATING INFORMATION
Graticule
The graticule is marked on the inside of the crt faceplate,
providing accurate, parallax-free measurements . The
graticule is divided into eight vertical and ten horizontal
divisions . Each Full Scan division is a 0 .9-centimeter square
divided into five minor divisions . A Reduced Scan graticule
is etched in the center of the Full Scan graticule . Each
Reduced Scan division is exactly one-half of a Full Scan
division
(0 .45 centimeter) . The vertical gain and horizontal
timing of the plug-in units are
calibrated to the graticule so
that accurate measurements can be made from the crt . The
illumination of the graticule lines can
be varied with
the
GRAT ILLUM
control
.
Figure 2-3 shows the graticule and defines the various
measurement lines . The terminology defined here will be
used in all discussions involving measurements
from the
graticule . Notice the
0%, 10%, 90%, and 100% markings on
the left side of the graticule . These
markings are provided
to facilitate rise-time measurements .
SECOND CENTER TENTH
VERTICAL VERTICAL VERTICAL
LINE

LINE

LINE
Light Filter
Figure 2-3 . Definition of graticule measurement lines
.
The tinted crt face-plate filter
minimizes light reflections
from the face of the
crt to improve contrast when viewing
the display under
high-ambient-light conditions . This filter
may be removed
for waveform photographs or for viewing
high-writing-rate
displays . To remove the filter, pull
outward on the
bottorn of the plastic crt mask and remove
it from the crt bezel . Remove
the tinted filter ; leave the
clear plastic face-plate protector installed
and replace the
mask . The face-plate protector
should be left in place at all
times to protect the crt face plate from scratches .
WARNING
Operating Instructions--7834
Do
not
remove
the clear plastic implosion
shield covering
the
crt face plate, the crt
implosion shield
provides
protection
to the
operator from crt implosion .
An optional mesh filter is available from Tektronix (in-
cluded with Option 3) . This filter provides shielding against
radiated EMC (electromagnetic compatibility) from the
face of the crt . It also serves as a light filter to make the
trace more visible under high-ambient-light conditions . The
mesh filter fits in place of the plastic tinted filter . Order the
filter by Tektronix Part 378-0603-00 .
Control Illumination
The CONTROL ILLUMINATION switch sets the
illumination level of the A and B INTENSITY indicators,
the A and B TRIGGER SOURCE switches, and of the
lighted push button switches on the plug-in units . The
positions available are OFF, MEDIUM, and HIGH . This
switch is located on the rear panel of the 7834 . The
CONTROL ILLUMINATION switch does not affect the
function-indicator lights (such as triggered or single-sweep
ready lights)
.
Intensity Controls
The A INTENSITY control determines the brightness of
the display produced by the plug-in unit installed in the A
HORIZ compartment ; the B INTENSITY control deter-
mines
the brightness of the display produced by the plug-in
unit installed in the B
HORIZ compartment . The READ-
OUT intensity control affects the
brightness of only the
readout portion of the crt display .
> `J CAUTION
lM/~a~a\i\i
.
./~
Crt phmphar damage can occur under adverse
conditions . Avoid any condition where an
extremely bright, sharply-focused dot exists on
the crt Also, remember
that the
light
filter
reduces the apparent light
output from the crt .
The beam current is limited during X-Y mode operation
or
when either, or both, time-base units being displayed are
set for a slow sweep
rate
.
This reduces the danger of damag-
ing the crt . esphgr with a
stationary or slowly moving
spot .