AT&T DS1/DMi/ISDN-PRI Line Equalizer and Compensation Settings, System 85 Traditional Modules

DS1 TRANSMISSION AND CABLING 3-9

LINE EQUALIZER AND COMPENSATION SETTINGS

The Generic 1 and Generic 2 DS1 circuit packs generate a signal that is preequalized. Preequalized means that the bipolar signal is shaped so that when it reaches the cable end it conforms to the DSX- 1 power specification.

System 85 Traditional Modules

Traditional modules may be equipped with the ANN11_ and ANN35 circuit packs. Preequalization is provided by properly setting the three equalizer switches, on the circuit packs. The three switches must be set for either half or all of the distance to the far end. The correct equalizer and compensation setting is determined based on the cable configuration. If a DS1 terminates at a NCTE or DSX-1 cross-connect, the total distance to the NCTE or DSX-1 should be used. If a DS1 terminates on another DS1, then half the distance to the other interface should be used. This setting is done in increments of about 133 feet [see table 3-1, System 85 Traditional Module Equalizer Settings (Metallic Cable)].

TABLE 3-1.System 85 Traditional Module Equalizer Settings (Metallic Cable)

Distance to Midpoint		ANN11_, ANN35
or Endpoint (FT)		Switch Settings
22 AWG ABAM & 24 AWG PDS	26 AWG PDS	1	2	3
0 to 133	0 to 90	ON	ON	OFF
133 to 266	90 to 180	ON	OFF	ON
266 to 399	180 to 270	ON	OFF	OFF
399 to 532	270 to 360	OFF	ON	ON
532 to 665	360 to 450	OFF	ON	OFF

NOTE: The ANN11_ and ANN35 circuit packs only have three switches. Off (1) is away from the switch number; on (0) is toward the switch number.

Generic 1 and Generic 2 Universal Modules

For TN722_ and TN767 circuit packs, preequalization is provided by properly administering the line compensation field. Compensation adjustments are described in the appropriate Generic 1 and Generic 2 administration manuals.

Pinouts for the cables connecting these circuit packs are given in System 85 R2V4 to DEFINITY Communications System Generic 1.1 via ISDN PRI Access (555-037-233), DEFINITY Communications System Generic 1.1 to 4ESS via ISDN PRI Access (555-037-234), and DEFINITY Communications System Generic 2.1 to 4ESS via ISDN PRI Access (555-037-237).