Tektronix 5110, Инструкция по эксплуатации

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Operating lnstructions-5110
GENERAL OPERATING INFORMATION
Intensity Control
The setting of the INTENSITY control may affect the
correct focus of the display. Slight adjustment of the
FOCUS control may be necessary when the intensity level
is changed. To protect the crt phosphor, do not turn the
INTENSITY control higher than necessary to provide a
satisfactory display.
WARNING I
Damage to the crt phosphor can occur under
adverse conditions. Avoid any condition where an
extremely bright, sharply focused spot exists on the
crt.
Apparent trace intensity can be improved by reducing
the ambient light level or using a viewing hood. Also, be
careful that the INTENSITY control is not set too high
when changing the time-base unit sweep rate from a fast
to a slow sweep rate, or when changing to the X-Y mode of
operation.
Display Focus
If a well-defined display cannot be obtained with the
FOCUS control, even at low INTENSITY control settings,
re-setting
of the internal astigmatism adjustment may be
required (adjustment must only be made by qualified
service personnel).
To check for proper setting of the astigmatism adjust­
ment,
slowly turn the FOCUS control through the op­
timum setting with a signal displayed on the crt screen. If
the astigmatism adjustment is correctly set, the vertical
and horizontal portions of the trace will come into
sharpest focus at the same position of the FOCUS control.
Beam Finder
The BEAM FINDER switch provides a means of
locating a display that overscans the viewing area either
vertically or horizontally. When the BEAM FINDER switch
is pressed, the display is compressed within the graticule
area and the display intensity is increased. To locate and
reposition an overscanned display, use the following
procedure:
1. Press the BEAM FINDER switch, hold it in, then
increase the vertical and horizontal deflection factors until
the display is within the graticule area.
2. Adjust the vertical and horizontal position controls
to center the display about the vertical and horizontal
centerlines.
3. Release the BEAM FINDER switch; the display
should remain within the viewing area.
Graticule
The graticule of the oscilloscope is marked on the
inside of the faceplate of the crt providing accurate, no­
parallax measurements. The graticule is divided into eight
vertical and ten horizontal divisions; each division is 0.5-
inch (1.27 centimeters) square. In addition, each major
division is divided into five minor divisions. The vertical
gain and horizontal timing of the plug-in units are
calibrated to the graticule so accurate measurements can
be made from the crt.
When making time measurements from the graticule,
the center eight divisions provide the most accurate time
measurements. Position the start of the timing area to the
second vertical graticule line and set
the time-base unit so
the end of the timing area falls between the second and
tenth vertical graticule lines.
Trace Alignment
If a free-running trace is not parallel with the horizontal
graticule lines, set the TRACE ROTATION adjustment
(rear-panel adjustment) as follows; Position the trace to
the center horizontal line and adjust the TRACE
ROTATION
adjustment so that the trace is parallel with
the horizontal graticule lines.
Calibrator Signal
The internal calibrator of the oscilloscope provides a
convenient signal source for checking basic vertical gain
and sweep timing. The calibrator signal is also very useful
for adjusting probe compensation, as described in the
probe instruction manual. The output square-wave
voltage is 400 millivolts, within 1%, and the square-wave
current is 4 milliamperes, within 1%. The frequency of the
square-wave signal is twice the power-line frequency. The
signal is obtained by clipping the probe to the loop.
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