27
CHAPTER 4: Operation
which is which. In the event of an interruption, leased-line modems automatically
reconnect when the data line or power is restored.
4.4.1 S
ETUP
1. Open the modem and change jumper J10 to select leased-line operation.
Then change jumper J11 to select either originate or answer mode. See
Chapter 3
for the full procedure.
2. Connect a modular telephone cable to the LINE jack on the modem.
Connect the other end of the cable to a two-wire leased-line jack or terminals
supplied by the telephone company.
3. Turn on the modem. The modem immediately attempts to connect to the
modem at the other end of the leased line. If the remote modem has not yet
been configured for leased-line operation, you may turn off the local modem
until the remote one is ready.
4. Leased-line setup is complete.
4.4.2 O
PERATING
D
ISTANCES
American Wire Gauge (AWG)
Data rate (bps)
19
22
24
28
2400
22
15
12
9.5
miles
4800
19
13
10
8
miles
9600
15
10
7
5.5
miles
19,200
11.9
7
5
4
miles
33,600
10
6
4.23
miles
Wire Diameter (mm)
Data rate (bps)
0.9
0.65
0.5
0.32
2400
35.4
24.1
19.3
15.2
km
4800
30.5
20.9
16
12.8
km
9600
24.1
16
11.2
8.8
km
19,200
19.1
11.28
6.4
km
33,600
16
9.6
6.7
4.8
km
These figures apply only to “dry” lines unamplified by the telephone
company. Among other things, leased-line operating distances depend
upon data rate, wire diameter, impairments, cable type, manufacturer,
m-splices, bridge taps, etc. If you have any additional questions about
distances, please contact your telephone company representative.
