TECHNICAL DESCRIPTION AND OPERATING MANUAL ST131 <PIRANHA II> and ST131N
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To use the detailed pattern, you need to press
and
being in the «BAND» mode with
not more than 200 MHz bandwidth. If the pattern has not been created, it appears: "The pattern was
not created yet."
When the "AUTOMATIC ANALYSIS" sub-mode is used, the bandwidth value could be any, up to the
maximum frequency range. Read more about working in this mode (see section 3.4)
Features of these pattern are following:
Spectral resolution.
In first and second methods spectrums are recorded with a resolution corresponding to the resolution
of the screen. This resolution can be checked by pressing
. For instance, the spectral resolution
in the FULL RANGE mode is 16 MHz and in the BAND mode for the 0.5 KHz bandwidth is 19 Hz.
Herewith the threshold sensitivity in the FULL RANGE mode is about -90 dBm, while in the BAND mode
for the 0.5 KHz bandwidth is about -160 dBm.
If you use a third method, detailed pattern will have a fixed frequency resolution 40 KHz.
Location for recording of patterns.
To avoid capture "dangerous" signals to the pattern, recording must be performed at a distance from
the place of work. This distance is determined by considering that the level of the "dangerous" signals
is below the threshold sensitivity of the ST131 at the place of creating the pattern and consequently
only “legal” signals will be recorded.
Ten meters or more will be enough for the first and second methods in the FULL RANGE mode. For
the bandwidth below 10 MHz in BAND mode and for the detailed pattern it is fifty meters or more.
Restrictions.
It should be noted that in first two methods use of a pattern is limited by the fact that band of the
pattern should be equal to the current working band. Thus, considering the purpose of search signals,
it means if you work in FULL RANGE mode, only one pattern is enough. If you need a sequential shift
band after the band, you have to create the patterns for all these bands.
It can be done by writing patterns for all bands and later recalling them from memory (second
method). Also you can make pattern from a predetermined distance each time after switching to the
next band and return to the place of work (first or second methods).
In third method, there is no such difficulties. The detailed pattern exists as unified for the entire
frequency range so you can use it for any frequency band you set.
Generally, use of the detailed pattern is preferably, but sometimes, using first two methods is justified.
For example, when there is a limited time or inability to provide enough distance from a work place to
make pattern. Anyway, joint using all these methods is possible.
