Hameg Instruments HM5530 Manual Del Usuario página 31

CENTER
Center frequency setting either via the keyboard
knob . Prior to any entry, the pushbutton must be depressed if it was
not already lit; the tuning knob will be active immediately. A number
entry will be displayed in the left readout fi eld; it will be accepted after
a (second) depression and shown in the center frequency readout fi eld
(CF ... MHz). Legal values are from 0 to 3000 MHz. The signal at the
center frequency will be displayed in the screen center, provided the
SPAN is unequal to 0.
SPAN
Span (dispersion, sweep width) = the frequency range which is dis-
played on the screen. The span is adjusted either by number entry
via the keyboard or with the tuning knob
pushbutton must be depressed unless it was already lit; the tuning
knob will be active immediately. A number entry will be displayed in
the left readout fi eld; it will be accepted after a (second) depression
and shown in the span readout (SF ... MHz). Legal values are 0 or 1 to
3000 MHz; entries 0 but 1 MHz will be accepted as (SF = 1 MHz).
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Span and center frequency settings determine the start (left) and stop
(right) frequencies displayed.
Note:
The specifi ed frequency range is 0.1 to 3000 MHz; any
readings 0.1 MHz may be unreliable.
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Example: If the center frequency is 300 MHz and the span
STOP
is 500 MHz, the sweep and the display will extend from
50 MHz (START) at the left of the graticule (300 MHz – ½
span) to 550 MHz at the right (STOP) of the graticule (300
MHz + ½ span).
Start and stop frequencies can be read/set directly by
depressing the respective pushbuttons, sidestepping the
calculation.
Note:
The instrument displays the sweep time in the readout
(SW ... ), it adapts the sweep time automatically with
respect to the span and fi lter settings (RBW) and (VBW). If
the sweep speed can not be slowed down further, „uncal"
STOP
or with the tuning
ZERO SPAN, after setting the span to (SF = 000.000 MHz), is a special
operating mode. The instrument converts to a selective voltmeter of
the center frequency signal. The level is indicated by the vertical shift
of the baseline in 10 or 5 dB/div. This is similar to a scope displaying
a pure dc level.
Adjustment/display of the start frequency. The adjustment is performed
either via the keyboard
pushbutton must be depressed unless it was already lit; the tuning knob
. Prior to any entry, the will be active immediately. A number entry will be displayed in the left
readout fi eld; it will be accepted after a (second) depression and shown
in the start frequency readout fi eld (SR ... MHz) in place of the center
frequency (CF ... MHz) display. Legal values are 0 to 3000 MHz.
The choice of a pair of start and stop frequencies is another method
of selecting the spectrum displayed on screen resp. setting center
frequency and span. No calculations of start and stop from center
frequency and span are necessary. If center frequency and span were
set fi rst, a depression of the START pushbutton will display the start
frequency.
If an illegal combination of start and stop frequencies like START
STOP is chosen, the instrument will set both values equal which equals
ZERO SPAN, see SPAN
Adjustment/display of the stop frequency. The adjustment is performed
either via the keyboard
pushbutton must be depressed unless it was already lit; the tuning knob
will be active immediately. A number entry will be displayed in the left
readout fi eld; it will be accepted after a (second) depression and shown
in the stop frequency readout fi eld (ST ... MHz) in place of the span (SF
... MHz) display. Legal values are 0 to 3000 MHz. A depression of the
STOP pushbutton will display the stop frequency.
If an illegal combination of start and stop frequencies like START
STOP is chosen, the instrument will set both values equal which equals
ZERO SPAN, see SPAN
C o n t r o l s a n d r e a d o u t
will be displayed in place of the sweep time in order to
warn that the amplitude measurements may be wrong.
START
or the tuning knob
.
STOP
or the tuning knob
.
Subject to change without notice
. Prior to any entry the
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. Prior to any entry, the
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