Lesson 3/Learning Event 3
(f) Nonlinear distortion.
The nonlinear distortion section
consists of four push button switches.
The SIGNAL LEVEL switch, when
depressed allows measurement of the total nonlinear distortion test signal.
The 2ND ORDER and 3RD ORDER switches, when depressed measures only the
second and third order product of the test signal, respectively. The LEVEL
ZERO push button switch is used in conjunction with the level and frequency.
When the test set is adjusted to the desired reference frequency, pressing
the LEVEL ZERO switch will establish a zero dB reference. All the following
measurements will be made in dB relative to this reference point. If the
LEVEL ZERO switch is not pressed, all measurements will be absolute dBr.
b. The nonlinear distortion test is an optional test, and must be
requested when ordering the test set, so these switches may not be on all
the TIMS.
c. The TIMS can be used to perform the majority of the parameter tests
established to maintain daily operation of DCS voice circuits.
There is
approximately 16 or more tests that can be performed using the TIMS. Some
of the tests are:
(1) Frequency response.
(2) Background noise.
(3) Basic noise C-message.
(4) Noise-to-ground.
(5) Nonlinear distortion.
(6) Peak-to-average ratio (P/AR).
(7) Single tone interference.
58
Previous Page
