Manual

16
Redbox User Handbook No 2
MATCHING CONVERTERS - RB-LI2
5 RB-LI2 Stereo Line Isolation Unit
Introduction
Fig 5-1: 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 dierent mains power
supplies, or dierent 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.
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.
System Block Diagram
Fig 5-2: RB-LI2 System Block Diagram.
MATCHING CONVERTERS
5
Gain
Input
Isolated Output
Transformer Balanced Mode
Ground Link
Jumper
Loop
Output
X2