Raytheon SNV-12, Инструкция по установке и эксплуатации

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SNV-12 Operations Manual
3-78
SW5- 6, 7 – RX Output Audio Delay
These switches are used to configure a delay on the output audio from the SVM-2 to the voted
audio bus. Essentially, this buffers the audio in the SVM-2 before it is output to the voted
audio bus. This is useful, for example, when MDC telegrams are used at the beginning of a
field transmission. In this case the time to detect receiver COR and perform the initial vote on
the audio might be long enough that the initial portion of the MDC might be cut off. The RX
output audio delay can be used to buffer the audio to give the system time to vote before the
MDC telegram is received. This delay is independent of the RX site audio delay controlled by
SW1.
NOTE: It is preferable to compensate for MDC telegrams arriving too
close to the start of transmission by modifying the radio system to
increase the “front porch” time for the transmissions. The RX output
Audio Delay function is meant as a secondary option for the case when
modifying the radio system is not possible.
NOTE: To properly configure the SNV-12 the RX Output Audio Delay
should first be set to disabled. Next, the RX Site Audio Delay (SW1)
should be used to compensate for line delays between the receiver and
the SVM modules. Once the RX Site Audio Delay is set properly (so that
audio is synchronized across all sites), the RX Output Audio Delay can
be applied equally to all SVM-2 Modules to compensate for initial vote
time. It is important that this delay is equal across all SVM modules to
maintain audio synchronization.
Table 3-72 RX Output Audio Delay
SW5-6,7 RX Output Audio Delay
00 Disabled *
01 100ms
10 200ms
11 400ms