Raytheon SNV-12, Инструкция по установке и эксплуатации

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SNV-12 Operations Manual
3-36
SW2-7 Site Unsquelch Time Limiter
This feature faults any site that remains continuously unsquelched for more than 3 minutes.
This was intended to benefit systems where a continuous radio link brings the remote receiver
audio to the voter. The purpose is to remove from consideration for voting sites that become
unsquelched because the remote link transmitter has failed (so no pilot tone is being
transmitted) while the local link receiver is always unsquelched (so the high noise volume
prevents the SVM‟s speech detector from activating the Line Fault Detection feature). The
fault will be removed as soon as the site again becomes squelched.
Table 3-17 Site Unsquelch Time Limiter
Enable
SW2-7 Unsquelch Time Limiter
OFF Disabled *
ON Enabled
SW2-8 Low Frequency Response
The CIM DSP circuitry has a high pass filter that is designed to remove low frequency energy
(such as 60 Hz AC hum) from the input audio passband. The high pass filter should be engaged
for normal operation as only the audio above 300 Hz is used in most communications systems.
This should be disabled only if it is necessary to pass low frequency data such as CTCSS, DCS,
etc. If the filter is disabled, careful shielding, equipment grounding and site grounding are of
increased importance. If SW2-8 is switched to On, the high-pass filter is removed, extending
the pass band from a 100 Hz cutoff to below 50 Hz. The default setting leaves the filter in
place. (The CIM‟s high pass filter only affects console-generated audio/tones; it has no effect
on repeat audio.)
Table 3-18 CIM High-Pass Filter
SW2-8 High-Pass Filter
OFF Engaged *
ON Removed