QUESTION:
Can I connect a Sync reference to a T1 tie cable to transport the signal from location A to B? The distance is less than 180ft and is an interior cable.
ANSWER:
YES. Generally speaking, intrabuilding DS1 connections can be achieved by cable (22 gauge ABAM) lengths of up to 655 feet, assuming that one end is at a DSX-1 reference point. 180 feet should not be a problem. However, depending on the equipment, there may be a line-build-out setting (in the transmitter) that must be set correctly.
A Sync reference typically has high level, all-ones outputs that meet the same standards (pulse shape, etc) as traffic carrying circuits. Just like wiring for a traffic path, care must be taken to properly terminate cables with the correct load impedance and avoid wiring stubs that may cause reflections and pulse distortion. BITS shelves and other Sync sources typically do not have lightning protective circuitry, so wiring must stay within the building. The limit of 655 ft of standard cable is approximately the cable length at which the level is down 20 dB, well within the normal operating range of a "bridging input".
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