A-9
Cisco VG224 Voice Gateway Hardware Installation Guide
OL-5006-04
Appendix A Cable Specifications and Information
Analog Voice Multiport Pinouts (RJ-21X/CA21A)
V.35 Connections
The V.35 standard is recommended for speeds up to 48 kbps, although in practice it is used successfully
at 4 Mbps. The Cisco VG224 voice gateway supports speeds up to 2.048 Mbps.
Use the V.35 serial transition cable (not included) with the Cisco 12-in-1 connector on one end and a
standard 34-pin Winchester-type connector (as shown in Figure A-9) on the other. The 34-pin
Winchester-type connector can be male for DTE or female for DCE. To order a cable, see the “Obtaining
Technical Assistance” section on page 16.
Figure A-9 V.35 Serial Transition Cable Connectors
X.21 Connections
The X.21 connector uses a 15-pin connector for balanced circuits and is commonly used in the
United Kingdom to connect to the public data network. X.21 relocates some o f the logic functions to the
DTE and DCE interfaces and, as a result, requires fewer circuits and a smaller connector than
EIA/TIA-232.
Use the X.21 serial transition cable (not included) with the Cisco 12-in-1 connector on one end and a
DB-15 connector (as shown in Figure A-10) on the other. The DB-15 connector can be male for DTE or
female for DCE. To order a cable, see the “Obtaining Technical Assistance” section on page 16.
Figure A-10 X.21 Serial Transition Cable Connectors
EIA/TIA-530 Connections
The EIA/TIA-530 standard, which supports balanced transmission, provides the increased functionality,
speed, and distance of EIA/TIA-449 on the smaller, DB-25 connector used for EIA/TIA-232. Like
EIA/TIA-449, EIA/TIA-530 refers to the electrical specifications of EIA/TIA-422 and EIA/TIA-423.
Although the specification recommends a maximum speed of 2 Mbps, EIA/TIA-530 is used successfully
at 4 Mbps or faster speeds over short distances. Cisco VG224 voice gateway supports speeds up to 2.048
Mbps.
Use the EIA/TIA-530 serial transition cable (not included) with the Cisco 12-in-1 connector on one end
and a DB-25 connector (as shown in Figure A-11) on the other. The DB-25 connector can be male for
DTE or female for DCE. To order a cable, see the “Obtaining Technical Assistance” section on page 16.
1
8
15 9DCE
DTE
194833
194834
DTE
DCE