Tektronix 2236 - OPERATORS FAMILIARIZATION; General Operating Information; Graticule Usage for Measurements; Grounding for Reliable Measurements

Section
3— 2236
Operators
OPERATORS FAMILIARIZATION
1
n П
B
n
п
GENERAL OPERATING INFORMATION
GRATICULE
The graticule is internally marked on the faceplate of the
crt to enable accurate measurements without parallax error
( see Figure 3-1 ) . It is marked with eight vertical and ten hori
zontal major divisions . Each major division is divided into
five subdivisions . The vertical deflection factors and horizon
tal timing are calibrated to the graticule so that accurate
measurements can be made directly from the crt . Also , per
centage markers for the measurement of rise and fall times
are
located
on
the left
side
of
the
graticule
.
1ST OR LEFT
VERTICAL
GRATICULE
LINE
11TH OR
RIGHT
VERTICAL
GRATICULE
LINE
1
1
П
100
GROUNDING
The most reliable signal measurements are made when
the 2236
and the unit
under test
are
connected by a
com
mon reference ( ground lead ) , in addition to the signal lead or
probe . The probe's ground lead provides the best grounding
method
for
signal
interconnection and
ensures the
maxi
mum amount of signal - lead shielding in the probe cable . A
separate ground lead can also be connected from the unit
under test to the oscilloscope GND connector located on
the
front
panel
.
RISE
AND
FALL
TIME
MEASUREMENT
PERCENTAGE
MARKERS
CENTER
VERTICAL
GRATICULE
LINE
CENTER
HORIZONTAL
GRATICULE
LINE
4207-09
1
ក
П
For
floating
Multimeter
measurements
the - (
negative
)
connector ( located on the right side panel ) should be con
nected to the lower impedance point of the unit - under - test
being
measured , to
minimize loading
.
Fig . 3-1 .
Graticule measurement
markings
.
SIGNAL
CONNECTIONS
on the accuracy of a displayed waveform . To maintain the
original frequency characteristics of an applied signal , only
high - quality , low - loss coaxial cables should be used . Coaxi
al cables should be terminated at both ends in their charac
teristic impedance . If this is not possible , use suitable
impedance
- matching
devices .
Generally , probes offer the most convenient means of
connecting an input signal to the instrument . They are
shielded to prevent pickup of electromagnetic interference ,
and the
supplied 10X
probe offers a high
input
impedance
that minimizes circuit loading . This allows the circuit under
test to operate
with a
minimum of change from
its normal
condition as
measurements are
being made .
INPUT
COUPLING
CAPACITOR
PRECHARGING
| 1
П
П
Л
When the Input Coupling switch is set to GND , the input
signal is
connected
to ground
through the
input
coupling
capacitor in series with a 1 - M2 resistor to form a
Coaxial
cables
may
also be
used to
connect
signals
to
the input connectors , but they may have considerable effect
C
3-1