AT&T 1987 AT&T Telephone User Manual


 
Port Specifications (Contd)
VOICE TERMINAL PORTS
STATION TYPE
CIRCUIT PACK
SPECIFICATIONS
Tip and Ring
Tip Ring Line
Single-Line Sets
(ZTN78)
l-Pair Interface (Tip and Ring)
(Analog)
Analog signals modulated over DC
loop
Loop Voltage: 24 V dc
Signaling: Dual Tone Multifrequency
(DTMF) only
REN (max.): 1.2
DC Current (max.): 35 mA
Loop Range (24 AWG ): 2,000 feet
In-building service only
Tip and Ring
Analog Line
Single-Line Sets
(TN742)
I-Pair Interface (Tip and Ring)
(Analog)
Analog signals modulated over DC
loop
Loop Voltage: 48 V dc
Signaling: Dual Tone Multifrequency
(DTMF) only
REN (max.): 5.0
DC Current (max.): 40 mA
Loop Range (24 AWG): 24,000 feet
Supports Out-of-Building, Extended
(greater than 2000 feet), Off-Premises
and Bridged Station services
(maximum of five bridged stations,
and two off-hook simultaneously).
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