Raytheon SNV-12, Инструкция по установке и эксплуатации

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SNV-12 Operations Manual
3-77
SW5-4 COR Delayed with Receive Audio
When RX audio delay is added using an SVM‟s rotary switch SW1, the COR (unsquelched)
indication can either be reported immediately or delayed along with the RX audio.
When not delayed, the audio delay is used to compensate for other system delays so that the
site is voted and repeaters keyed, etc., before the audio is passed through the system.
By turning on dipswitch SW5-4, the reporting of active COR following its detection is delayed
by the same amount as the RX audio. This can be useful when the voter is used to select from
among signals arriving from very different media. For example if most sites are linked by
microwave, but one site is linked via satellite, it‟s easier to ensure proper voting if the positive
COR (unsquelched condition) is delayed along with the audio.
The ability to delay COR is not available with SVM-1 modules. See Section 5.7 for more
information.
Table 3-70 COR Delayed with Rx Audio
SW5-4 COR Delay
OFF COR Not Delayed *
ON COR Delayed
SW5-5 Pilot Tone Sensitivity Reduction
This switch allows the pilot tone sensitivity to be reduced by approx 7 dB. This may assist
operation in environments where local environmental noise (or added noise, such as alternator
whine) at the same frequency as the pilot tone sometimes causes falsing of the pilot tone
detector. Falsing means that the RX audio at the pilot tone frequency causes the SVM to
incorrectly determine (usually momentarily) that an SVM is squelched. If this feature is
enabled, it‟s important that the pilot tone be generated at a high level (preferably at the same
level as voice audio).
The Pilot Tone Sensitivity Reduction Feature is not available with SVM-1 modules.
Table 3-71 Pilot Tone Sensitivity Reduction
SW5-5 Pilot Tone Sensitivity
OFF Not Reduced *
ON Reduced by approx 7 dB