Learning Event 2:
DESCRIBE THE USES OF A SIGNAL GENERATOR
A signal generator is a test device which generates an alternating voltage
signal suitable for test purposes.
generating a signal of any desired frequency. The signal may be either modulated
or unmodulated and is used for the following checks or tests:
a. Alignment of tuned
b. For frequency measurements, its use is limited
The signal generator is used primarily in the alignment of tuned circuits. A
signal generator is classified according to its frequency and is one of two types:
audio frequency or radio frequency.
a. Audio frequency generators produce signals with a frequency range from 20
Hz to 20kHz.
b. Radio-frequency generators produce signals covering a range of frequencies
from 10 kHz to 10 GHz.
Many radio-frequency generators have audio outputs
separately available through front panel jacks. These outputs are normally 100 and
When using the generator, the output test signal is coupled into the circuit
being tested, and its progress through the equipment is traced by the use of high-
signal generators, calibrated networks of resistors, called attenuators, are
These are used to regulate the voltage of the output signal and also
provide correct impedance values for matching the input impedance of the circuit
Accurately calibrated attenuators are used, because the signal
strength must be regulated to avoid overloading the circuit receiving the signal.
There are many types of signal generators. They may be classified roughly by
frequency into audio signal generators, video signal generators, radio frequency
generators, frequency-modulated RF generators, and special types which combine all
of these frequency ranges.
Audio signal generators.
a. Audio signal generators produce stable audio-frequency signals used for
testing audio equipment. Video signal generators produce signals which include the
audio range and extend considerably further into the RF range.
b. In both audio and video generators, the major components include a power
regulation circuits are necessary to ensure stability of the oscilla-