0049-1200-XXX RM16M – USER’S GUIDE 12/29/2010
Rev. C
Page 22
of
27
APPENDIX C – TELEPHONE LINE CABLES
Table C-1 lists the function of the modular jacks on the back panel of the Data Shelf. The figure that
follows Table C-1 shows a typical telephone-line cable configuration. The last two figures show DDS
cable configurations.
Table C-1. Modular Jack Pin Functions
TELCO Jack
TELSET/LL Jack
Pin Function Pin
Function
1
2
R
T
Xmit pair of DDS
modems. Not used on
other type modems
1
2
Xmit pair (Dial backup modems
only)
3
R1/MI
Receive ring for
leased line
modems. Mode
indicator for
dialup modems.
3 Not
used
4
R
Ring – dial or leased
4
Not used
5
T
Tip – dial or leased
5
Not used
6
T1/MIC
Receive tip or leased
line modems. Mode
indicator common for
dialup modems.
6 Not
used
7
8
PR
PC
Programmable resistor
connections for dial
network modems.
7
8
Rec pair (Dial backup modems
only)
7
8
T1
R1
Rec pair for DDS type
modems.