Paradyne Comsphere 3550 Series Quick Reference Manual page 8

Connecting the Model 3550 DSU to the Dial Network (PSTN)
If your DSU is equipped with a V.32 DBM, follow these steps.
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Procedure
1. Plug either end of the dial (analog) interface cable into the DSU jack labeled
BACKUP.
— Permissive service – telephone cord with 6-pin modular RJ11C plug
— Programmable service – telephone cord with 8-pin RJ45S plug
2. Plug the other end of the cable into the modular jack provided by the telephone
company, USOC RJ11C (permissive) or USOC RJ45S (programmable).
3. If your site has programmable service, verify that the DSU's hardware strap S1-1 is
switched to the Off position.
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