Freedom R8100 SERIES, Руководство оператора

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Selects the signal source used for the R8100 frequency counter and decode functions. When set to Internal
the recovered audio or tones from a demodulated received signal are used as the signal source. The
External setting directs an externally applied signal at the Meter In port to the R8100 frequency counter
and decode circuits.
2.2.5.5 Frequency Counter
In Monitor mode, this soft key enables a general-purpose frequency counter for the recovered baseband
audio or IF frequency displayed in the modulation scope (Figure 2.2.5.5-1 Frequency Counter screen).
In Generator mode the counter measures the frequency of the internal or external modulation applied to
the RF carrier. In External Scope mode the counter measures the frequency of signals applied to the Meter
In port.
Input Decoding
Selects the signal source used for the R8100 frequency counter and decode functions. When set to Internal
the recovered audio or tones from a demodulated received signal are used as the signal source. The
External setting directs an externally applied signal at the Meter In port to the R8100 frequency counter
and decode circuits.
Resolution
Activates a horizontal submenu with selections for the counter resolution. The settings include 0.1 Hz,
1.0 Hz, and 10 Hz resolution.
Figure 2.2.5.5-1 Frequency Counter screen
2.2.5.6 RF Scan
Searches for the strongest RF signal that is above the “Squelch Opens @” setting on the active RF input
port. The R8100 locks onto and automatically centers its operating frequency on this carrier (Figure
2.2.5.6-1). The search frequency range in MHz is entered using Start Frequency and Stop Frequency soft
keys. Scanning begins once the Scan, Start soft keys are selected. Scanning can be manually stopped by
selecting the Scan, Stop soft keys. The meter graph displays an automatically-scaled spectrum of the entire
scan range. Once a signal is acquired the RF Scan meter stays locked on that frequency even if the carrier
disappears. It resumes scanning once the Scan, Start soft keys are selected. The RF Scan meter operates
only when it is highlighted; otherwise it becomes inactive.