Figure 3.1 Trunk Line Loop Start Signalling; Table 3.4 Electrical Characteristics Of The T1 Trunk Line - Samsung OfficeServ 7200 General Description Manual

OfficeServ 7200 General Description Guide
2.1.1 Signalling Type of the Trunk Line
Loop Start
When processing the loop start signals, the on-hook and off-hook status is con-
trolled by the flow of the electric current. The loop is a closed loop trunk circuit or
standard 2500-type set loop.
T1 Trunk Line
The electrical characteristics of the T1 trunk line should comply with the ITU G.703
and G.704 standards.
Transfer speed
Code
Pulse type
Transmission media
Load resistance
Indicated (pulse) nominal peak voltage
Signal Power at the frequency of
Level 772 kHz
Power at the frequency of
1544 kHz
The signalling specifications and signalling method of the T1 trunk line should
comply with the ITU G.703 and G.704 standards.
© Samsung Business Communications
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GND
T
E
-48 VDC
(C.O.)

Figure 3.1 Trunk Line Loop Start Signalling

Table 3.4 Electrical Characteristics of the T1 Trunk Line

Category
CHAPTER 3. OfficeServ 7200 Specifications
T
E
Specification
1544 kbit/s ±50 ppm
AMI or B8ZS
Regular square wave : When indicating all valid signals,
comply with the mask (G.703) regardless of the codes.
Pair of twisted lines
120 Ω
3.00 V
±12 ~ ±19 dBm
25 dB or higher when the power is less than the power
at the frequency of 772 kHz
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Keyphone
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