Artel DigiLink DLC170, Установка и эксплуатация

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DLC170 Function Modules Installation and Operations Manual 29
Understanding and Using the DLC170DA
Table 9. DIP Switch SW2 Settings
Function Selected Operation
Position
S1 S2 S3 S4 S5 S6 S7 S8
EMS override Enabled: DL Manager can change
the DLC170DA module
configuration.
ON
Disabled: DL Manager cannot
change the DLC170DA module
configuration.
1
OFF
1. If the module is operating in EMS Override mode, as indicated by a green OK LED on the front panel, then the
EMS Override DIP switch has no effect until you use DL Manager to take the module out of override mode and set it
to local mode (see the
DL Manager Setup and Operations Manual ).
Configuring Peak Analog Audio Level with Rotary Switch SW4
Rotary switch SW4 controls the peak analog audio level that will be produced by the DLC170DA. The peak
audio level is referred to as 0 dB Full Scale (0 dBFS). The information that follows provides an understanding of
the 0 dBFS concept and how you can adjust for it on the DLC170DA.
When analog audio is converted to digital, the audio is represented by a series of binary values. The highest
signal that can be represented occurs when the values are either all zeros or all ones. Attempting to exceed
these values causes the audio waveform to be clipped and distorted. The maximum level is called Full-Scale
and all audio levels can be described as levels below the full-scale value. If the signal is just at full scale, it is
called 0 dBFS. A normal operating level might be -18 dBFS, or 18 dB below clipping.
The SW4 rotary switch on the DLC170DA allows the output analog voltage level to be matched to the correct
digital level. This switch setting is expressed as the peak audio output in dBm (into 600 Ohms) required to
reproduce 0 dBFS. If the peak program level in a typical installation is defined as +20 dBm, then when the
switch is set to position 5, a tone at the maximum digital value is converted to an analog signal at +20 dBm.
Figure 18 shows the DLC170DA configuration switch SW4 located on top of the PCB.
Figure 18. DLC170DA Configuration Switch SW4
Note: When using the DLC170DA with the DLC170AD, set the peak audio level rotary switches on both
function modules to the same setting to achieve unity gain.
(Continued)