Tektronix 1L40, Instruction Manual

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Operating Instructions— Type 1L40
Fig. 2 -2 . Change as indicated on this p a rtia l schematic o f the Vertical A m p lifie r.
Center frequency range (radio frequency)— That range
of frequencies which can be displayed at the center of
the reference coordinate.
When referred to a control
(e.g., Intermediate Frequency Center Frequency Range) the
term indicates the amount of frequency change available
with the control.
Dispersion (sweep width)— The frequency sweep excur­
sion over the frequency axis of the display. Can be express­
ed as frequency/full frequency axis, or frequency (Hz)
division in a linear display.
Display flatness —Uniformity of amplitudes response
over the rated maximum dispersion (usually in units of dB).
Drift (Frequency drift)— Long term frequency changes or
instabilities caused by a frequency change in the spectrum
analyzer local oscillators. Drift limits the time interval that
a spectrum analyzer can be used without retuning or reset­
ting the front panel controls (units may be Hz/s, H z/1 ° C,
etc).
Dynamic range (on screen)— The maximum ratio of
signal amplitudes that can be simultaneously observed with­
in the graticule (usually in units of dB).
Dynamic range (maximum useful)— The ratio between
the maximum input power and the spectrum analyzer sensi­
tivity (usually expressed in dB).
Frequency band — The range of frequencies that can
be covered without switching.
Frequency scale — The range of frequencies that can
be read on one line of the frequency indicating dial.
Incidental frequency modulation (residual frequency
modulation)— Short term frequency jitter or undesired
frequency deviation caused by instabilities in the spectrum
analyzer local oscillators. Incidental frequency modulation
limits the usable resolution and dispersion (in units of Hz).
Incremental linearity — A term used to describe local
aberrations seen as non-linearities for narrow dispersions.
Linear display — A display in which the vertical deflec­
tion is a linear function of the input signal voltage.
Linearity (dispersion linearity)— Measure of the compari­
son of frequency across the dispersion to a straight line
frequency change. Measured by displaying a quantity of
equally spaced (in frequency) frequency markers across the
dispersion and observing the positional deviation of the
markers from an idealized sweep as measured against a
linear graticule. Linearity accuracy, expressed as a percenf-
A W
age is within —^ — X 100%, where A W is maximum po­
sitional deviation and W is the full graticule width.
Maximum input power —The upper level of input
power that the spectrum analyzer can accommodate w ith­
out degration in performance (spurious responses and signal
compression). Usually in units of dBm.
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