Tektronix 2213, Инструкция по эксплуатации

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THEORY OF OPERATION
Section 3 —2213 Service
INTRODUCTION
SECTION ORGANIZATION
This section contains a functional description o f the
2213 Oscilloscope circuitry. The discussion begins w ith a
general summary o f instrument functions followed by a
detailed description o f each major circuit. Functional
block diagrams and schematic diagrams are used to show
the interconnections between parts o f the circuitry, to
indicate circuit components, and to identify interrelation­
ships w ith the front-panel controls.
Schematic diagrams and the overall block diagram are
located in the tabbed "Diagrams" section at the back o f
this manual. The schematic diagram associated w ith each
description is identified in the text and indicated on the tab
of the appropriate foldout page by a numbered diamond
symbol. For best understanding o f the circuit being
described, refer to both the appropriate schematic diagram
and the functional block diagram.
INTEGRATED CIRCUIT DESCRIPTIONS
Digital Logic Conventions
Digital logic circuits perform many functions w ithin the
instrument. Functions and operation o f the logic circuits
are represented by logic symbology and terminology.
Most logic functions are described using the positive-logic
convention. Positive logic is a system o f notation whereby
the more positive o f tw o levels is the TRUE (or 1) state;
the more negative level is the FALSE (or 0) state. In this
logic description the TRUE state is referred to as HI, and
the FALSE state is referred to as LO. The specific voltages
which constitute a HI or a LO state vary between specific
devices. For specific device characteristics, refer to the
manufacturer's data book.
Linear Devices
The functioning o f individual linear integrated circuit
devices in this section use waveforms or other techniques
such as voltage measurement and simplified diagrams to
illustrate their operation.
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