Tektronix 1710J Series, Instruction Manual

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1710J-Series Waveform Monitors
5–1
Theory of Operation
The material in this section is subdivided into a general description, which is
supported by the simplified and main block diagrams, and the detailed circuit
descriptions that use the schematic diagrams as illustrations. A thorough
understanding of the instrument starts with knowing how the major circuit
blocks fit together, which is then followed by an understanding of the individual
circuit’s functions. These discussions of the 1710J-Series Waveform Monitor
begin with a brief, fundamental overview, then proceed on to the block diagram,
and then go on to the individual circuit descriptions.
Overview
The 1710J-Series Waveform Monitor is a specialized oscilloscope. It is designed
to monitor and measure television baseband signals. See Figure 5–1. Signals
input through either of the rear-panel 75
W
bridging loop-through inputs are
synchronously displayed on a CRT.
Vertical
Inputs:
CH A
CH B
EXT REF
Front panel
controls
Microcontroller
Horizontal
Remote
interface
Sync
CRT
Switching
RGB Enable,
RGB Input, RGB/YRGB
Switching
Figure 5–1: Simplified representation of a 1710J-Series Waveform Monitor
Front-panel mode switching is accomplished by a series of push-button switches
whose status is being constantly polled by a microprocessor. In turn, the
microprocessor controls switching functions and circuit gains so that the
instrument can perform as a monitor or be used to make specific measurements.