GatesAir PT-353, Инструкция по установке и эксплуатации, Страница: 26 / 55

PT/PR-353 Program Audio Module Installation & Operation Manual 3 – Installation & Operation
Version 1.1
3-12 GatesAir
Intraplex Products
3.3.5 Programmable Gain Settings (GAIN)
A 16 position rotary switch (SW1) sets the input gain on the PT-353 module and output gain on the
PR-353 module. This switch is labeled GAIN, designated SW1 and is set to position B, as a factory
default on both the transmitter and receiver. Figure 3-6 shows an example of SW1.
Figure 3-6. Switch 1 - Input/Output Gain Control (Shown Set to Position 0)
The PT-353 input sensitivity switch sets the level at which the input audio signal produces a digital full
scale in the A/D encoder. The PR-353 output gain switch sets the maximum output level that the D/A
decoder creates before clipping (in other words, the interpreted value of a received digital full scale
signal). Table 3-6 defines these settings. The factory default setting for these four switches is B,
providing a maximum peak level before clipping of +20 dBu.
Table 3-6. Gain Switch Settings
Switch
Setting
Input Sensitivity
(TX Gain) or
Maximum Output Level
(RX Gain) in dBu
0 +9
1 +10
2 +11
3 +12
4 +13
5 +14
6 +15
7 +16
8 +17
9 +18
A +19
B +20
(factory default setting)
C +21
D +22
E +23
F +24
3.4 Drop and Insert Operation
A drop and insert multiplexer operates at a central point on a three (or more) point system. In Figure
3-6, Site 2 has a drop and insert multiplexer with the DI-A port connected to the transmission line to