Lesson 3
DESCRIBE THE BASIC ELECTRONIC TELEVISION TEST SIGNALS
TASK
Describe and identify five basic electronic television test signals.
CONDITIONS
Given information
and
illustrations
pertaining
to
the
basic
television
test
signals.
STANDARDS
Demonstrate competency of task skills and knowledge required for identification of
the test signals discussed in this lesson, by correctly responding to 80% of the
multiple-choice test questions covering five basic electronic television test
signals.
REFERENCES
None
LEARNING EVENT 1:
DESCRIBE THE MULTIBURST SIGNAL AND GRAY-SCALE LINEARITY TEST
SIGNAL
1. The multiburst signal consists of a white-flag reference pulse, followed by six
bursts of individually keyed sine waves in ascending frequency order. This signal
is useful as a quick systems check for rapid visual presentation of amplitude-
frequency response, usually to 4.2 MHz.
a. The basic block diagram of a multiburst generator is shown in Figure 3-1.
The unit normally receives composite sync and composite blanking from the local
sync generator. For field use, self-contained (internal) is usually available.
b. Horizontal drive is derived from incoming sync and used to trigger and
synchronize six individual sine wave oscillators.
It is also used to generate a
white-flag pulse at the beginning of active horizontal sweep.
(1) Normally, the white-flag pulse width is adjusted for 8 microseconds.
The
trailing edge of this pulse triggers
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