Depending on your system setup, your callers hear an opening menu providing instructions that allow them to use a touch-tone® telephone to reach the appropriateTo install the Synapse system correctly, follow the Recommended Installation Phone Extension Prefix of the first Deskset you installed, manually change. This User's Guide provides instructions for using your Synapse SB67020/SB67025. Deskset telephone with software version 3.1.0 or newer. Synapse Administrator s Guide Advanced American Telephones. Ipiphony Phone System User Manual 1 P a g e About this Guide This guide explains how to use Shop AT&T for home telephones and landline phones for home and small office use. Synapse administrator's guide (software ver. 3.1.1/3.1.2) Download. H A P T E R VERVIEW The Synapse® Business Phone System from AT&T is for businesses that need up to 100 extensions. This system is scalable from 1 to 39