Appendix A: Phone Jack Descriptions; Dial-Line Pin Functions; Telset/Leased-Line Pin Functions - Black Box 325 User Manual

Appendix A: Phone Jack Descriptions

A.1 Dial-Line Pin Functions
The 8-pin phone jack connects to the PSTN dialup lines. Pin functions for this jack are:
Pins 1, 2—Not used
Pin 3 MI—Switch hook on exclusion-key telephone
Not used in some systems
Pin 4 R—Ring side of telephone line
Pin 5 T—Tip side of telephone line
Pin 6 MIC—Switch hook on exclusion-key telephone
Pin 7 PR—Data-jack program position
Pin 8 PC—To data-jack program resistor
A.2 Telset/Leased-Line Pin Functions
The 8-pin TELSET/LEASED LINE jack allows a standard telephone set or a leased line to be connected
to the modem. The pin functions for this jack are:
Pins 1, 2—Transmit pair—4-wire leased line or TX and RX for 2-wire leased line
Pins 4, 5—Ring and tip (respectively) of telephone line for TELSET
Pins 7, 8—Receive pair—4-wire leased line
APPENDIX A: Phone Jack Descriptions
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