Introduction To Spectrum Analysis - Hameg HM5010 Manual

Introduction to Spectrum Analysis

20
frequency is set to 500MHz, a generator signal must be applied to
the input. The output level should be between 40 and 50 dB above
the noise.
C: Set generator frequency to 500MHz. Adjust the peak of the
500MHz spectral line to the horizontal screen center using the X-
POS. control (16).
D: Set the generator frequency to 100MHz. If the 100MHz
spectral line is not on the 2nd. graticule line from left, it should
be aligned using the X-AMPL. control (17). Then the calibration
as described under C should be verified and corrected if
necessary. The calibrations C and D should be repeated until
optimum adjustment is achieved.
The analysis of electrical signals is a fundamental problem for
many engineers and scientists. Even if the immediate problem
is not electrical, the basic parameters of interest are often changed
into electrical signals by means of transducers. The rewards for
transforming physical parameters to electrical signals are great,
as many instruments are available for the analysis of electrical
signals in the time and frequency domains.
The traditional way of observing electrical signals is to view them
in the time domain using an oscilloscope. The time domain is
used to recover relative timing and phase information which is
needed to characterize electric circuit behavior. However, not all
circuits can be uniquely characterized from just time domain
information. Circuit elements such as amplifiers, oscillators,
mixers, modulators, detectors and filters are best characterized
by their frequency response information. This frequency
information is best obtained by viewing electrical signals in the
frequency domain. To display the frequency domain requires a
device that can discriminate between frequencies while
measuring the power level at each. One instrument which
displays the frequency domain is the spectrum analyzer. It
graphically displays voltage or power as a function of frequency
on a CRT (cathode ray tube).
In the time domain, all frequency components of a signal are
seen summed together. In the frequency domain, complex signals
(i.e. signals composed of more than one frequency) are separated
into their frequency components, and the power level at each
frequency is displayed. The frequency domain is a graphical
Subject to change without notice