Rb-Li2 Stereo Line Isolation Unit; Introduction; System Block Diagram; Fig 8-1: Rb-Li2 Front Panel - Sonifex Redbox Series User Handbook Manual

8 Matching Converters - RB-LI2

8 RB-LI2 Stereo Line Isolation Unit

Introduction

Fig 8-1: RB-LI2 Front Panel.

The RB-LI2 stereo line isolation unit is used to isolate audio signals from
inter area ground hum loops, which could be caused by equipment being
powered by different mains power supplies, or different phases on the
same supply. The input and output are connected together through
a transformer, which has internal jumpers allowing the outputs to be
balanced about ground.

System Block Diagram

Input
Loop
Output

Fig 8-2: RB-LI2 System Block Diagram

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There is also a loop-through output, so that the RB-LI2 can be inserted into
a line, forming a transformer balanced distribution point.
This unit is useful where audio is required to be driven over a relatively
long length of cable. By isolating the signal using transformers, ground
loop currents that can be present in non-isolated signals, are eradicated
completely.
Gain
Transformer Balanced Mode
Ground Link
Jumper
X2
Isolated Output