Installing and putting a SINAUT modem into operation
6.4 MD2 dedicated line modem
SINAUT ST7 Station control system - System Manual
260
System Manual, 05/2007, C79000-G8976-C178-06
Maximum range (km)
Core diameter 0.9 mm
1200
36.2 – NTP x 0.9
36.6 – NTP x 0.5
42.8 – NTP x 0.9
43.3 – NTP x 0.5
2400
29.6 – NTP x 0.6
30 – NTP x 0.2
35 – NTP x 0.6
35.4 – NTP x 0.2
9600 / 19,200
11.9 – NTP x 0.9
12.6 – NTP x 0.1
14.2 – NTP x 0.9
15 – NTP x 0.1
Core diameter 1.2 mm
1200
50.1 – NTP x 1.3
50.7 – NTP x 0.7
59.3 – NTP x 1.3
60 – NTP x 0.7
2400
43.4 – NTP x 0.8
44 – NTP x 0.3
51.4 – NTP x 0.8
52 – NTP x 0.3
9600 / 19,200
17.2 – NTP x 1.3
18.3 – NTP x 0.2
20.5 – NTP x 1.3
21.6 – NTP x 0.2
Core diameter 1.4 mm
1200
59.2 – NTP x 1.5
60 – NTP x 0.8
70.1 – NTP x 1.5
70.9 – NTP x 0.8
2400
54.3 – NTP x 1
55 – NTP x 0.4
64.3 – NTP x 1
65 – NTP x 0.4
9600 / 19,200
20.6 – NTP x 1.5
22 – NTP x 0.2
24.6 – NTP x 1.5
26 – NTP x 0.2
NTP = number of tapping points
*) not permitted with postal leased lines. Transmit level must be set to –9 dB.
The values in the table are guidelines.
When calculating the maximum range, a power margin of 4 dB was included. This is to
compensate for fluctuations in cable properties that experience has shown to occur in
practise, and thus always ensure that sufficient signal level is available for problem-free data
transmission. To calculate the values shown in the table, the following formula was used:
[ ]
Cable
LTOP
Insert
Cable
LTOP
Res
Send
A
A
A
NTP
A
A
N
N
N
S
×
+
×
−
×
−
−
+
=
2
2
min
max
A
Insert
Insertion loss per tapping point [in dB]
A
Cable
Attenuation per km of the cable used [in dB]
A
LTOP
Attenuation per LTOP [in dB]
NTP
Number of tapping points
N
min
Minimum receive level [in dB]
(-43 dB for MD2, please use only absolute value in formula)
N
Send
Transmit level [in dB]
(normally –6 dB or 0 dB)
N
Res
Power margin [in dB]
S
max
Max. range [in km]
Sample calculation:
For core diameter 0.8 mm, at 2400 bps, with LTOPs and transmit level –6 dB
