BRUEL & KJAER 1022 Instructions And Applications page 27

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the B.F.a. via a screened transformer e.g. TU 0005, the B.F.a. being
grounded at one terminal.
Due to the selectivity of the Frequency Analyzer it is well-suited as an
indicating instrument in a bridge circuit. The decibel scale on the instrument
meter will often prove useful when it is desired to measure the quality of
different components placed within the bridge.
Measurement of Gain in A. F. Amplifiers
The measurement of distortion and frequency response of A. F. amplifiers
may be carried out in the same manner as for four-terminal networks, the .
description for the arrangement being given in the initial paragraph to this
.section.
Frequently it Is important to check the linearity of an amplifier i.e. to
measure the gain for different values of input voltage. As the attenuator
circuit of the 1022 is very accurately calibrated .it is an extremely useful
instrument in carrying out these measurements.
The output voltage from the amplifier under test should be measured
with an Audio Frequency Voltmeter 2409 or a Microphone Amplifier 2603
or a Measuring Amplifier 2606 an example of the arrangement being given
in Fig.5.3 .
Amplifier
Fig.5.3. Measurement of gain in an AF amplifier
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