Vii.7 Audio Checking - Prodys PortaNet User Manual

When no link line is detected on the communication interface, the word "DOWN"
is displayed.

VII.7 Audio checking

PortaNet is equipped with a Vu meter on the top panel, and furthermore it offers
the possibility to get audio level information from the display by pressing the INF
key in the menu keypad. Let's take a look at both types of information:
The VU meter on the top panel measures the audio level just before the
compressor/limiter. This level corresponds to the sum of all the inputs which
contribute to the program line (line 1), that means, all those inputs whose led is
on GREEN. This Vu meter comprises several green leds and a red overload led.
The audio levels obtained from the display with the INF key are digital domain
measurements. The input levels are measured before the compression and the
output levels are obtained after de decoding process, as can be seen from the
following diagrams:
TalkBack Rx
PortaNet User Manual
L 1 : D O W N
L 2 : D O W N
CUE
D/A
D/A
I S D N
L : > > > > > >
R : > > > > >
LINE 1
Decoder
1
Program Rx
L : > > > > > >
R : > > > > >
LINE 2
Decoder
2
TalkBack Rx
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