Promax HD Ranger +, Руководство пользователя

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4-44 December 2014
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Min. Hold : (Off/Permanent/Curtain). It allows the user to display the
current signal with the minimum values measured for each
frequency. The OFF option disables this function. The
Curtain option displays the minimum values in green for a
moment with the current signal. The Permanent option
maintains minimum signal on the screen. This option is
useful for detecting interferences in TV cable or identify
deterministic interference in analogue and digital channels.
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Persistence : When active, the signal is displayed on a coloured
background. The signal prior to current signal persists for a
while before disappearing so the user can see how the signal
changes easily.
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Filter Type : (Max / RMS). It allows the user to select between maximum
peak detector or RMS detector. The maximum peak detector
is mainly used for analogue modulated signals, while the
RMS option is the right choice for digital modulated signals.
The MAX peak detector is mostly used for analogue
modulated signals, while the RMS is the proper choice for
digital modulations. The maximum peak detector causes the
noise floor to rise, according to the RMS to peak ratio. That
same effect causes digital signals to apparently grow in level
when maximum peak detector is used.
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Vertical Range : It allows to adjust the vertical scale on screen. Available
values are 1, 2, 5 and 10 dB per division.
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Dashed BW : When it is ON the channel bandwidth area is hatched by
lines.
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Reference : (Set / Clear). It memorizes the current trace on screen,
which can be used as a reference for further comparison. It
may be also very helpful for visually measure the gain or
attenuation in a TV distribution network. To delete the
reference, select the "clear" option. It can also be activated
by a short press on the export key in the Spectrum Analyzer
mode.