Patton electronic 2720 user manual Options Network, Internal, External

dClocking: Network (default)

Options: Network, Internal, External

Network: This is the most commonly used setting when connect ing to a carrier’s network. In this mode, the unit recovers the clock from the received signal and uses it to transmit data. In this way the unit remains synchronized to a master clock.

Incampus applications, one of the units must be set to Internal clock, and the other end is set to Network clock. At all times, there must be only one clock source. Otherwise, clock slips and framing errors and bit errors may occur.

Internal: This is commonly used in campus applications, where the unit is not connected to the public telephone network directly. In this mode, the unit uses the on-board oscillator as the transmit clock source.

eLine Build Out (dB): 0 – 133 feet, 0 dB (default)

Options: -7.5 dB -15.0 dB -22.5 dB

This controls the transmitter signal strength and pulse shape. For most applications, the default setting will suffice. When connecting to a carrier connection, the carrier will determine what LBO is necessary.

0dB provides the highest signal strength and therefore the longest dis- tance, while –15.0 dB provides the lowest usable signal strength. The last setting, –22.5 dB, is usually only used to test the line and should not be used in normal applications.

fESF Data Link: ANSI T1.403 (default)

Options: ANSI T1.403, AT&T TR54016

ANSI T1.403: This ANSI developed standard (see ANSI T1.403- 1995: Network-to-Customer Installation—DS1 Metallic Interface) uses the FDL to send and receive one second Performance Report Messages (PRMs). The messages con- tain the NI performance over the last four seconds. Thus, up to three consecutive messages may be lost without loss of information. It is available only with ESF. When ANSI T1.403 is selected, requests to send AT&T performance reports (ref. AT&T TR 54016) are ignored.

AT&T TR54016: Developed by AT&T, this FDL method differs principally from the ANSI method in two ways: First, the ANSI method transmits messages continuously, whereas the AT&T method transmits a performance report only upon a request from the remote end for a report. Second, the AT&T method provides a historical summary, up to the last 24 hours, of NI performance. Only the service provider or special test equip- ment can send these requests. When AT&T TR54016 is selected, ANSI PRMs are still transmitted by the unit, but only PRMs sent by the carrier will be recognized. To receive PRMs from another customer unit (i.e., in a campus application), select ANSI T1.403. When the frame is not ESF, the FDL is disabled.

gESF Carrier Loops: Enabled (default)

Options: Enabled, Disabled

The ESF format provides the CO the ability to put the customer installation’s Model 2720 into loopback mode. The Model 2720 recog- nizes these special messages that are sent over the FDL. When enabled, the unit will respond to these loopback commands and go into or out of loopback mode. When disabled, the unit will not respond, although it still recognizes the loopback commands. When in loopback, the unit will remain in loopback until a loopback exit command is received or when the loopback timer times out. See Unit Options (Section 3.2.4) to make Loop Timeout choices. This feature allows the remote user to regain control should one be locked out after a loop- back is initiated.

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