Raytheon SNV-12, Инструкция по установке и эксплуатации

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SNV-12 Operations Manual
3-57
3.12.5.4 CPM Switch S4 Settings
NOTE: Factory settings are marked *.
NOTE: The function served by SW4 changes if the COR Lock feature is
enabled. A full explanation follows.
S4 Voting Criteria; Transition Timer
S4 determines the time that one site must exhibit a better SNR or noise level than the presently
voted site before the SNV-12 will change the voted site. If site "A" is presently voted, site "B"
must maintain a better signal than site "A" by the amount set by the CPM switches SW2-1, 2, 3
for the entire duration of the time set by SW4 in order to be voted over site "A". The ideal
position for this setting depends on the system requirements for voting speed and smoothness
of voting operation. See Section 5.6.
Table 3-48 SW4 As Voting Transition Timer
Position Delay Position Delay Positio
n
Delay Position Delay
0 Do not use 4 200ms 8 400ms C 2 sec
1 50 ms
5 250ms *
9 500ms D 2.5 sec
2 100ms 6 300ms A 1 sec E 3 sec
3 150ms 7 350ms B 1.5 sec F 5 sec
Position 0 is for testing purposes only.
The Voting Criteria default settings of 1 dB (set by SW2-1, 2, 3) and 250 msec will work well
with most systems. Settings below 1 dB or 100 ms are likely to yield unsatisfactory results, as
a change in the currently voted site could occur merely due to the random nature of noise,
causing the voter to hop from site to site. Higher level and delay settings may be helpful in
systems where less frequent voting transitions are desired; that is, in systems were it‟s preferred
that the voter hold a particular site unless another site becomes much better.