Zhone Technologies Network Device Foreign Exchange Office FXO Card, Characteristics, PCM Coding

Zhone Technologies, Inc.		IMACS Product Book, Version 4
	Characteristics
	Nominal Transmit TLP	Software configurable, -10.0dB to +5.0dB, steps of 0.1dB
	Nominal Receive TLP	Software configurable, -10.0dB to +2.0dB, steps of 0.1dB
	2-Wire Return Loss	>28 dB Echo, >20 dB singing (against 600 ohm, in series with 2.16 uF
		with additional 25 ohm resistor between tip and ring)
	PCM Coding	Software configurable, A-Law, A-Law inverted, u-Law
	Transhybrid Loss	Echo: 20dB, SRL-LO: 12dB, SRL-HI: 12 dB
	Standards Conformance
	AT&T TR43801	Digital Channel Bank Requirements and Objectives - November 1982;
	Bel1Core TR-NWT 000057	Functional Criteria for Digital Loop Carrier System - January 1993
	BellCore GR-63-CORE	Network Equipment-Building System (NEBS) Requirements: Physical
		Protection
	ITU-T G.712	(11/96) - Transmission Performance Characteristics of Pulse Code
	ITU-T Q.552	Modulation (replaces G.712, G.713, G.714 and G.715)
		Transmission Characteristics of 2 -wire analog interface of a Digital
		Exchange
	FCC Part 68	Requirements for Connection of Terminal Equipment Systems and
		Protective Apparatus to the Telephone Network
	FCC Part 15	Subpart 15
	UL 1459	UL Standard for Safety, Telephone Equipment

2. Foreign Exchange Office (FXO) Card

The IMACS supports only one variant of Foreign Exchange Office (FXO) card:

•813960/813970 FXO Card provides eight 2-wire analog ports with terminating impedance of 600 ohms.

FXO cards can be installed in any of the User Slots of the IMACS chassis. FXO cards encode the incoming analog voice signals into 64 Kbps PCM format before transmission onto the network. A Ringing Generator is required if one or more FXO ports in a system are programmed to operate in Manual Ringdown (MRD) mode. In addition, a physical jumper must be set on the FXO card for each port programmed for MRD operation. Each FXO card provides a single 50-pin female AMPHENOL connector (RJ27X).

All port parameters are software configurable on a port-by-port basis. The Mode setting specifies whether the port is to be used for standard Foreign Exchange Office, Foreign Exchange Software Defined Network, Dial Pulse Terminate, or Manual Ring Down (MRD). As described above, the MRD mode also requires the setting of physical jumpers. The Signal setting specifies Loop Start, Loop Start with Forward Disconnect, Ground Start, R2, and Immediate R2 operation. In “fxodn” and “dpt” modes, the user may also specify the wink duration time and wink delay from 0.1 seconds to 9.9 seconds in 0.1-second increments. The PCM Coding options supported include “∝ - Law”, “A-Law” and inverted A-Law. The user may select the Trunk Conditioning mode (“busy” or “idle”) that should be applied towards the attached equipment should the WAN facility that the port is connected to fail. In addition, both the Transmit (Tx) and Receive (Rx) TLP levels can be set in increments of 0.1 dB. The Tx TLP range is from -10.0 dB to +5.0 dB. The Rx TLP range is from -10.0 dB to +2.0 dB.

The user may also specify, on a port-by-port basis, whether to use North American ANSI standard ABCD signaling (which is the default) or ITU (CCITT) ABCD signaling by turning the signaling conversion setting “on” or “off.” The trans-hybrid balance may be specified as one of eight values (known as “set1” through “set8”) as well as for a customized user-specified terminating impedance (“user”). All eight values are identical and are set for a terminating impedance of 600Ω ± 2.15∝ F in the case of the Model 813960 FXO cards.

Software-initiated testing and diagnostics supported on FXO cards include the setting of both analog and digital loop backs towards the network and generating a Digital MilliWatt signal on a port-by-port basis. A robust set of Test functions allow the user to monitor and set the state of

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