REFERENCE INFORMATION
120
The term "hybrid lines" means that both system and analog phones can be connected to such
lines. In hybrid PBX, "non-digitized" (analogue electrical tone signal without conversion) is
switched.
Cable type
Purpose
User device
two-wire,
analogue municipal telephone cable, analogue office PBX
analogue telephone
two-wire, digital
PBX digital cable
digital telephone
four-wire, digital
PBX digital cable
digital system telephone
four-wire, hybrid
PBX hybrid cable
analogue system telephone
CABLES USED IN TELEPHONE LINE
Cable type
RJ connector
RJ connector pin #
Wire coloring
Modern
Obsolete
2-wire analog
RJ-9
2-3 – analog signal
green
orange
red
green
RJ-11/14/25
3-4 – analog signal
white and blue
blue
red
green
2-wire digital
RJ-11/14/25
3-4 – digital signal
white and blue
blue
red
green
4-wire digital
RJ-14/25
3-4 – digital signal
white and blue
blue
red
green
2-5 – PBX commands
white and orange
orange
black
yellow
4-wire hybrid
RJ-14/25
3-4 – analog signal
white and blue
blue
red
green
2-5 – PBX commands
white and orange
orange
black
yellow