X.21 Line Interface Cable For Modems; Figure 3-5 X.21 Interface Cable; Table 3-3 X.21 Line Speed And Cable Length - Hitachi GR2000-B Series Installation Manual

Hitachi Gigabit Router GR2000-B Series Installation Guide
3.2.3

X.21 Line Interface Cable for Modems

For connecting a modem or terminal adapter to a V.21 line interface, use Hitachi
cable type HN-F9531-B73H (5 m). The boundary with the network is the connector
on the modem or terminal adapter. The Figure 3-5 below is the diagram of the V.35
interface cable.
HDRA 68-Pin Connector
(Router Side)

Figure 3-5 X.21 Interface Cable

Consult Hitachi if you purchase a cable other the 5 m cable specified above, since
line speed differs depending on the length of a cable. The table below shows the
relationship between the line speed and the length of cables.
Table 3-3
No. Line Speed Range (Xbit/s)
2.4 ≤ X ≤ 1024
1
1024 < X ≤ 1536
2
1536 < X ≤ 3072
3
3072 < X ≤ 6144
4
3-6
X.21 Line Speed and Cable Length
Cable Length Limitation
16 m or less
10 m or less
5 m or less
1 m or less
M3
D-Sub 15-Pin Connector
(Line Side)
GR2K-GA-0007
Rev. 5.00