Table Of Contents
Installing the 75-120-Ohm Adapter Cable on E1 Multichannel Port Adapters
Product Number: CAB-ADPT-75-120(=), CAB-ADPT4PK-75-120(=)
This document describes how to connect the 75-120-ohm adapter cable on any Cisco 120-ohm E1 multichannel port adapter that must connect to a 75-ohm unbalanced G.703 E1 line. The 75-120-ohm adapter cable can be purchased individually (CAB-ADPT-75-120) or in prepackaged four-packs (CAB-ADPT4PK-75-120). This document contains the following sections:
The 75-120-ohm adapter cable connects Cisco 120-ohm E1 port adapters to 75-ohm unbalanced G.703 E1 lines. The adapter has an eight-pin RJ-48C connector on the 120-ohm side and dual BNC coaxial connectors (transmit and receive) on the 75-ohm side. Two switches on the 120-ohm side allow the outer conductor of the cable (the input port of the E1 port adapter) to be either isolated from or connected to a protected earth ground (see Figure 1). The 120-ohm E1 ports of your port adapter connect to the 75-120-ohm adapter cable using RJ-48C connectors and Category 3 or Category 5 shielded foil twisted-pair (FTP) cable with 120-ohm impedance (see Figure 2 and Figure 3).
Note Early versions of this cable do not have the ground switches.
Figure 1 75-120-Ohm Adapter Cable
Figure 2 E1 Multichannel Port Adapter Interface Cable and RJ-48C Connector
Table 1 shows the pinouts of the RJ-48C connector on the 75-120-ohm adapter cable.
Table 1 RJ-48C Connector Pinouts
1 Rx = receive.
2 NC = no connection.
3 Tx = transmit.
Connecting the 75-120-Ohm Adapter Cable
Connect the 75-120-ohm adapter cable between the port adapter and the 75-ohm unbalanced G.703 E1 line using the following procedure:
Step 1 Set the two ground switches to the desired position.
Note To ground the outer conductor of the cable, both switches must be in the down position. To isolate the outer conductor of the cable from ground, both switches must be in the up position (see Figure 1).
Step 2 Attach the Category 3 or Category 5 FTP cable directly to the RJ-48C port on the E1 multichannel port adapter.
Note To comply with CE marking requirements, use shielded foil twisted-pair (FTP) cable with 120-ohm impedance.
Step 3 Attach the network end of your Category 3 or Category 5 cable to your 75-120-ohm adapter cable.
Step 4 Attach the BNC connector of the 75-120-ohm adapter cable marked receive to the network device connector marked transmit.
Step 5 Attach the BNC connector of the 75-120-ohm adapter cable marked transmit to the network device connector marked receive.
Figure 3 Connecting a 75-120-Ohm Adapter Cable to a Multichannel E1 Port Adapter
These sections explain how to obtain documentation from Cisco Systems.
World Wide Web
You can access the most current Cisco documentation on the World Wide Web at this URL:
Translated documentation is available at this URL:
Cisco documentation and additional literature are available in a Cisco Documentation CD-ROM package, which is shipped with your product. The Documentation CD-ROM is updated monthly and may be more current than printed documentation. The CD-ROM package is available as a single unit or through an annual subscription.
You can order Cisco documentation in these ways:
•Registered Cisco.com users (Cisco direct customers) can order Cisco product documentation from the Networking Products MarketPlace:
•Registered Cisco.com users can order the Documentation CD-ROM through the online Subscription Store:
•Nonregistered Cisco.com users can order documentation through a local account representative by calling Cisco Systems Corporate Headquarters (California, U.S.A.) at 408 526-7208 or, elsewhere in North America, by calling 800 553-NETS (6387).
You can submit comments electronically on Cisco.com. In the Cisco Documentation home page, click the Fax or Email option in the "Leave Feedback" section at the bottom of the page.
You can e-mail your comments to firstname.lastname@example.org.
You can submit your comments by mail by using the response card behind the front cover of your document or by writing to the following address:
Attn: Document Resource Connection
170 West Tasman Drive
San Jose, CA 95134-9883
We appreciate your comments.
Obtaining Technical Assistance
Cisco provides Cisco.com as a starting point for all technical assistance. Customers and partners can obtain online documentation, troubleshooting tips, and sample configurations from online tools by using the Cisco Technical Assistance Center (TAC) Web Site. Cisco.com registered users have complete access to the technical support resources on the Cisco TAC Web Site.
Cisco.com is the foundation of a suite of interactive, networked services that provides immediate, open access to Cisco information, networking solutions, services, programs, and resources at any time, from anywhere in the world.
Cisco.com is a highly integrated Internet application and a powerful, easy-to-use tool that provides a broad range of features and services to help you with these tasks:
•Streamline business processes and improve productivity
•Resolve technical issues with online support
•Download and test software packages
•Order Cisco learning materials and merchandise
•Register for online skill assessment, training, and certification programs
If you want to obtain customized information and service, you can self-register on Cisco.com. To access Cisco.com, go to this URL:
Technical Assistance Center
The Cisco Technical Assistance Center (TAC) is available to all customers who need technical assistance with a Cisco product, technology, or solution. Two levels of support are available: the Cisco TAC Web Site and the Cisco TAC Escalation Center.
Cisco TAC inquiries are categorized according to the urgency of the issue:
•Priority level 4 (P4)—You need information or assistance concerning Cisco product capabilities, product installation, or basic product configuration.
•Priority level 3 (P3)—Your network performance is degraded. Network functionality is noticeably impaired, but most business operations continue.
•Priority level 2 (P2)—Your production network is severely degraded, affecting significant aspects of business operations. No workaround is available.
•Priority level 1 (P1)—Your production network is down, and a critical impact to business operations will occur if service is not restored quickly. No workaround is available.
The Cisco TAC resource that you choose is based on the priority of the problem and the conditions of service contracts, when applicable.
Cisco TAC Web Site
You can use the Cisco TAC Web Site to resolve P3 and P4 issues yourself, saving both cost and time. The site provides around-the-clock access to online tools, knowledge bases, and software. To access the Cisco TAC Web Site, go to this URL:
All customers, partners, and resellers who have a valid Cisco service contract have complete access to the technical support resources on the Cisco TAC Web Site. The Cisco TAC Web Site requires a Cisco.com login ID and password. If you have a valid service contract but do not have a login ID or password, go to this URL to register:
If you are a Cisco.com registered user, and you cannot resolve your technical issues by using the Cisco TAC Web Site, you can open a case online by using the TAC Case Open tool at this URL:
If you have Internet access, we recommend that you open P3 and P4 cases through the Cisco TAC Web Site.
Cisco TAC Escalation Center
The Cisco TAC Escalation Center addresses priority level 1 or priority level 2 issues. These classifications are assigned when severe network degradation significantly impacts business operations. When you contact the TAC Escalation Center with a P1 or P2 problem, a Cisco TAC engineer automatically opens a case.
To obtain a directory of toll-free Cisco TAC telephone numbers for your country, go to this URL:
Before calling, please check with your network operations center to determine the level of Cisco support services to which your company is entitled: for example, SMARTnet, SMARTnet Onsite, or Network Supported Accounts (NSA). When you call the center, please have available your service agreement number and your product serial number.
CCIP, the Cisco Arrow logo, the Cisco Powered Network mark, the Cisco Systems Verified logo, Cisco Unity, Follow Me Browsing, FormShare, iQ Breakthrough, iQ Expertise, iQ FastTrack, the iQ Logo, iQ Net Readiness Scorecard, Networking Academy, ScriptShare, SMARTnet, TransPath, and Voice LAN are trademarks of Cisco Systems, Inc.; Changing the Way We Work, Live, Play, and Learn, Discover All That's Possible, The Fastest Way to Increase Your Internet Quotient, and iQuick Study are service marks of Cisco Systems, Inc.; and Aironet, ASIST, BPX, Catalyst, CCDA, CCDP, CCIE, CCNA, CCNP, Cisco, the Cisco Certified Internetwork Expert logo, Cisco IOS, the Cisco IOS logo, Cisco Press, Cisco Systems, Cisco Systems Capital, the Cisco Systems logo, Empowering the Internet Generation, Enterprise/Solver, EtherChannel, EtherSwitch, Fast Step, GigaStack, Internet Quotient, IOS, IP/TV, LightStream, MGX, MICA, the Networkers logo, Network Registrar, Packet, PIX, Post-Routing, Pre-Routing, RateMUX, Registrar, SlideCast, StrataView Plus, Stratm, SwitchProbe, TeleRouter, and VCO are registered trademarks of Cisco Systems, Inc. and/or its affiliates in the U.S. and certain other countries.
All other trademarks mentioned in this document or Web site are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (0208R)
Copyright © 1999-2002, Cisco Systems, Inc.
All rights reserved.