Tektronix 2252, Operator'S Manual

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Operators Familiarization
INTRODUCTION
This section is divided into two subsections: BASIC OPERATION and MENU
SYSTEM OPERATION. BASIC OPERATION provides some general infor­
mation about the readout displays, graticule, and signal connections; MENU
SYSTEM OPERATION provides detailed information on the menus and func­
tions available under menu control.
BASIC OPERATION
This subsection contains the basic operating information and techniques that
should be considered before attempting any measurements. For location
and function of instrument controls, connectors, and indicators see How the
Controls Work, Section 2 of this manual.
Graticule
The graticule is internally marked on the crt face to provide parailax-free
viewing and enable accurate measurements {see Figure 3-1). The graticule
is marked with eight vertical and ten horizontal major divisions. Major
divisions are further divided into five subdivisions of 0.2 division each,
marked along the center vertical and horizontal graticule lines. Percentage
marks for rise-time and fall-tim e measurements are marked on the left side of
the graticule. Vertical deflection factors and horizontal timing are calibrated to
the graticule so that accurate measurements can be made directly from the
crt.
The waveform displays are calibrated to the crt graticule markings for making
quick and very accurate measurements of waveform parameters. Voltage
measurements are done by counting the vertical graticule divisions and
partial divisions occupied by the portion of the display being measured and
then multiplying by the VOLTS/DIV setting. Time measurements using the
graticule markings are done in a simitar manner. Count the number of hori­
zontal graticule divisions and partial divisions occupied by the portion of the
waveform being measured and multiply by the SEC/DIV setting.
To improve the accuracy of the estimate, position the display to take advan­
tage of the 0.2 division minor graticule markings on the center graticule lines.
Also position one of the measurement points of the waveform as precisely as
possible on one of the major graticule marks to be used as a measurement
reference point.
2252 Operators
3-1