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).
5-12
