VOICE BANDWIDTH PRIVATE LINE DATA CIRCUITS DESCRIPTION

Transcription

1 BELL SYSTEM PRACTICES AT&Ka Standard SECTION Issue 3, January 1981 VOICE BANDWIDTH PRIVATE LINE DATA CIRCUITS DESCRIPTION CONTENTS PAGE CONTENTS PAGE 1. GENERAL Ckuit Design for Data Only, 4-Wire Data Set APPLICATION OF PROTECTIVE ARRANGEMENTS Ckuit Design for Data Only, 2-Wke Data Set CHANNEL INTERFACE UNITS (CIU).. 2 A. General Ckuit Design far Data/Voie, 4-Wire Data Set B. Channel Interfae Levels Ckuit Design for Data/Voie, 2-Wire Data set C. Data Auxiliary Set 829-Typsr Type D1 HPDC Ckuit D. 150 Channel Servie Unit (CSU) Type D2 HPDC Cwuit With CO Swith in E. Laap-Bak Arrangements Same Rate Center as Cantroi Station SIGNALING ARRANGEMENTS Type D2 HPDC Ckuit With CO Swith not in Same Rate Center as ontrol Station CIRCUIT CONDITIONING CIRCUIT CONFIGURATIONS Ciruit Canversion of End link to Midlink A. 2-Point Cuuits Point Arrangement B. Muhipoint Ciruits Cembined Central OWe Swithed Multipoint Cirui t C. Central Offie Relay Swithed C:ruits Interstate Central OWe Relay Swithed Can figuration D. Customer Premises Swithed Ckuits Customer Swithing Arrangement SEALING CURRENT REFERENCES GENERAL F~ures 1. Referene far Voieband Data Transmission This setion desribes the voie bandwidth ( Hz) hannels used for private line (PL) data servies. Voie bandwidth data is defined as data signals oupying a single voie-frequeny hannel (approximately 300 to 3200 Hz or less with some types of failities). These servies inlude NOTICE Not for use or dislosure outside the Bell System exept under written agreement Printed in U.S.A. Page 1

2 SECTION data, telenletry, and alternate voie/data servie; for example, 2001 and 3002 hannels overed by FCC Tariff No These hannels may be used to provide 2-point, multipoint, and ertain swithing arrangements. The information in this setion inludes the desription of various types of onditioning that an be obtained on these different hannels This setioi, is r~issued to update and realign information onsistent with the Data General Layer, 314-O1O-ZZZ. Sine this is a general revision, no revision arrows have been used to denote signifiant hanges Desriptive information ommon to the transmission of data on the Publi Swithed Network (PSN), private line (PL) servies, and Swithed Servie Networks (SSN) is overed in the following setions: Data GeneralAnalog Transmission Parameters Desription (Setion ) o Data GeneralData Testing Priniples (Setion ) Data General Data Servies Support (Setion ) DataGeneral Interonnetion/Interpositioning (Setion ). A basi understanding of the Data General Setions is reommended prior to the use of this setion The referenes to various related voieband data maintenane setions are given in Fig. 1. Voie-only operation is not overed in this setion but may be found in the Division 310 and 311 series of praties Although operation of these servies is basially 2-point, ertain multipoint and swithed arrangements are also used. One-way, half-duplex, and full-duplex modes may be used. Both 2-wire and 4-wire failities and terminals are employed. Where 4-wire failities are used, an equal-level loop-bak arrangement is speified in all ases. 2. APPLICATION OF PROTECTIVE ARRANGEMENTS 2.o1 The standard means of terminating PL dat:i hannels is with the data auxiliary set (DAS) 829 hannel interfae unit (CIU). The DAS 82?9 provides signal level adjustments and equalization as required. It also provides maintenane features, suh as test jaks and equal-level loop-bak apability. These funtions are neessary in providing and maintaining the servie, and the DAS 829is therefore required in all installations involving Bell System and ustomer-provided equipment (CPE). 2.o2 Protetion of the network from hazardous voltages and longitudinal imbalanes is provided by inherent harateristis of the DAS 829. That is, the protetion is assured by omponents (diodes, transformers, fuses) whih are an integral part of the devie and essentially used in its other funtions. Signal level protetion is provided at the entral offie (CO) by means of surveillane. Customer transmit levels are not usually soures of trouble on PL data hannels. PL data hannels are designed for a fixed overall loss of 16 db, and therefore the ustomer does not have the inentive to raise the signal level to improve performane. 3. CHANNEL INTERFACE UNITS (CIU) 1.05 There is no differene tehnially in the transmission requirements of the 2000 series hannels when ordered for data operation and those of a 3002 hannel, exept in some ases (suh as PBX tie trunks) for standard 1OO4-HZ loss. The differene arises from appliations that are desribed in FCC Tariff No. 260 and the loal administration of these hannels. The 2000 series of hannels may be onneted to exhange and toll servies, but the 3002 hannel must not. A. General 3.01 The DAS 829 is the Bell System standard CIU for terminating 4-wire PL voieband data hannels. Other types of station equipment may be speified and are generally similar in funtion, suh as the older DAS 828. The work order reord detail (WORD) doument should indiate the type of station equipment to be used to provide protetion against potentially hazardous voltages and longitudinal imbalane. Page 2

3 1SS 3, SECTION s DATAPHONE OAA, FX, RX LOOPS DDD TRUNKS PBX -CO TRUNK A 0s ON PREMISE LINE Xu=!ux CCSA ACCESS LINE betn-data CONSIDERATIONS ETN SUITCH CCSA TRUNK AUTOVON~CCESS LINE &EPSCS SWITCH 0s AUTOVON SUBSCRIBER LINE t AUTOVON TRUNK I AUTOVON AUTOVON SNITCH SWITCH (OATEC ) Ds TWO-POINT OR IIULTIPOINT PRIVATE LINE O-ZZZ 0s k Fig. 1 Referene for Voieband Data Transmission Page 3

4 SECTION B, Channel Interfae Levels 3.02 The urrent standard transmit power at the data set interfae is O dbm. This design is used for those data sets whih an transmit at O dbm. The standard reeiver power at the data set interfae is -16 dbm. Typial arrangements showing the DAS 829 using these designs are shown in Fig. 2, f]. 4, and 5. 3.o3 The basi ground rules for determining 4-wire iruit design when using DAS 829- tspe are as follows: (a) Additional transmission iruit design guidelines for use with DAS 829-type are provided in Setion C. Data Auxiliary Set 829-Type 3.04 As previously mentioned, the standard CIU for 4-wire PL data iruits is the DAS 829. The physial interfae is the miniature 50-position ribbon plug provided as part of the mounting arrangement of the DAS 829 and assoiated data units. Additional information overing interonnetion/interpositioning is found in Setiu:: Additional information overing the 50-position ribbon plug and assoiated leads is found in Setion The modem interfae will be O dbm transmit and -16 dbm reeive The DAS 829 is available in three basi station odes as follows: (b) Equal-level loop-bak is always provided. DAS 829A 44A 1 OR 44A2 OATA MOUNTING TO 4-WIRE METALLIC FACILITIES T1 RI T 1 OT 1 TRANSMIT OR 1 0 obm -) DT. R DR / RECEIVE -16 OEM TO MOOEM LINE TERMINATION AND LEVEL CONTROL / TEK5 TEK6 p LINE STATUS / Fig. 2Ciruit Design for Data Only, 4-Wke Data set Page 4

5 KS 3, SECTION A1OATAMWtTIMi ( 11 Es Ilk I II I II 1 9 I I m. TO i%tw KTALLIC FACTI TTTFS T 1111 i LB1 I N--u-uLOSSLESS rbrio CIRCUIT Ill I IT 1 1 4@- TRANSR1? = Am RECEIVE - 18d6m [7R -1 TO MOOER LIE TERRINATIW AM LEVELWTROL II LB 1 TEK5 L IK STATUS TEK6 ] - -] ) Fq. 3Ckuit Design far Dotu Only, 2-Wke Data Set DAS 829B DAS 829C Any one partiular PL hannel termination requires the use of only one ode of CIU. The CIU ode that is used depends on the failities involved Eah of the three DAS 829 types is desribed as follows: DAS 829A is used for nonloaded or short loaded loops when no gain is required in transmit or reeive paths. Slope equalization is aomplished with 600- or 1200-ohm line terminations. Attenuation is aomplished in the transmit or reeive paths. DAS 829Bis used for nonloaded or short loaded loops. It is required for long nonloaded loops and provides 150-, 600-, or 1200-ohm line termination for slope equalization. Gain or attenuation an be provided in the reeive path. Attenuation is provided in the transmit path. DAS 829C is used for short nonloaded or for loaded loops and provides extensive equalization apability. This unit provides the same equalization apabilities as the 359A or the 359K equalizer. Gain or attenuation an be provided in the reeive path. Attenuation is provided in the transmit path. 3.o7 A standard, self-ontained, tone-ativated, loop-bak apability is present in eah DAS 829-type. Loop-bak is equal level and provides ontrolled impedanes Two data mountings, the 44A1 and 46A1, are designed for use with the DAS 829-type. Page 5

6 SECTION TO KEY TELEPHONE SET 45A1 OATA MOUNTING (NOTE} OAS 829-TYPE CIU 4BAI OATA UNIT rz%rl ALTERNATE VOICE CIRCUITRY TO 4-WIRE METALLIC FACILITIES 11 RI T I.z R LINE TERflINATION AND LEVEL CONTROL ẇb1=flb1 LB1 LB1 )(, 1 T: \ 1 )( p DR1 J OT -1 O lbm RECEIVE OR -16 dbm TEK5 LINE STATUS TEK6 xl OBU 1 OBU2 DIAL BACKUP STATUS TO t100em NOTE : SEE FIG. 3 FOR TEST JACK LOCATIONS Fig. 4Ckuit Design for Data/Voie, 4-Wire Data Set The 44A1 provides a single ard housing for one DAS 829-type. The 46A1 provides a housing for a maximum of eight DAS 829-type and an be any ombination of the three odes of DAS 829. The single ard mounting is the same size as the new data set 202 S/T, and the multiple housing is the same size as the data set 202 S/T multiple housing. These arrangements are onsiderably smaller than the equivalent DAS 828-type desribed in Setion Supplementary funtions of alternate voie and dial bakup are provided by data units, whih are plug-in iruit paks of the same size as the DAS-829-type. These are the 48A1 and the 48B1 data units, respetively. Various >ingle and multiple hannel termination arrangements are available and are desribed in Setions and The 2-wire data set option is provided by the use of the 48G1 data unit. A hybrid transformer provides the interfae between the 2-wire modem and the DAS 829-type CIU that terminates a standard 16-dB hannel. The transmit and reeive amplifiers in the transmit and reeive pairs of the 48G1 data unit have a fixed gain that offsets the iruit losses and provides a O-dB insertion loss in the transmit and reeive paths. D. 150 Channel Servie Unit (CSU) 3.11 The 150A hannel servie unit (CSU) is a passive devie whih provides a 2-wire interfae between voieband data station equipment and a 2-wire PL iruit. The 150A CSU provides the following 2-way transmission path 2-way protetion against hazardous voltages 2-way urrent surge protetion Page 6

7 . 1SS 3, SECTION TO KEY TELEPHWE SET 59A1 OATA MOUNTING (NOTE} OAS 829-TYPE CIU H,, #JPy ~ 48G OATA TO 4-WIRE METALLIC FACILITIES 11 [ R1 T R E 1, 1 1 d, 1 LB1 )t i,, LB1 LOSSLESS HYBRID CIRCUIT DT1 OdBm TRAMS141; ORl ;:EIVE =1: -16dBm TO t?ooem t LINE TERITINATIW ANO LEVEL CONTROL LB1 TEK5 LINE,EK6 STATUS =1 / I, I I I J MTE: SEE FIG. 3 FOR TEST JACK LOCATIONS, Fig. 5 Ckuit Design for Data/Voie, 2-Wire Data Set Balaned Signal termination level adjustment D isolation between the station equipment and the telephone failities. Additional information overing the 150 CSU an be found in Setion E. Leap-krk Arrangements 3.12 A remotely ontrolled equal-level loop-bak arrangement is required at the ustomer loation on those iruits whih may be aessed by an STC (or similar organization equipped with a voie-frequeny transmission testing apability). iruit is an integral part of all odes of the DAS 829-type To ativate the loop-bak at loations equipped with the 44A1 data unit, a Hz tone is applied toward the station at data level for not less than 5 seonds. Upon removal of the tone, the loop-bak path will be established. To deativate the loop-bak, the 2713-Hz tone is again applied for a minimum of 5 seonds. The 406A tone generator is available for use at the testboard to supply the 2713-Hz signal for ativation and release of the tone ativated loop-bak. More desriptive information on the 406A tone generator is given in Setion SIGNALING ARRANGEMENTS 3.13 The DAS 829-type has tone loop-bak iruitry whih operates like a DAS 828A equipped with a 44A1 data unit. The tone ativated loop-bak 4.01 When DAS 829-type is used at the station, inband, end-to-end loked-in signaling with 30-seond time-out an be provided by the addition Page 7

8 . SECTION of the 48A1 data unit. This data unit provides for alternate voie use of the PL and uses an inband signal of 2600-Hz for ringdown signaling. An interrupted tone signal is returned to the alling station to indiate that the alled station is reeiving the 2600-Hz signaling tone at -13 dbmo. A 2-wire telephone set is used. Additional information on this type of signaling is given in Setion Note: i he alternate voie arrangement provided by the 48A1 data unit is not interhangeable with alternate voie arrangements of either the DAS 828-type or loally engineered systems requiring 20-Hz ringdown signaling unless signal onversion equipment is provided On those installations where the DAS 829 is not used, as in the ase of the DAS 828, CO signaling equipment must be used. The typial arrangement uses a DIB ringdown onverter (SD ) or the Metalli Faility Terminal (MFT) ringdown onverter signaling unit (J99343EB). The ringdown onverter onverts a 20-Hz signal on the 4-wire simplex path to E&M signaling. The E&M signaling is ompatible with out-of-band signaling arrier hannels, suh as Nl, ON, or T arrier using Dl, D2, or D3 hannel banks. On arrier hannels requiring in-band signaling, suh as L and R, a single frequeny (SF) unit is used. 5. CIRCUIT CONDITIONING s.01 FCC Tariff No. 260 provides for a basi voiegrade hannel (2001, 3002) and eight types of C onditioning. These are designated as follows: 2001, 3002Basi hannel 1 C3 IJsed only for Swithed Servies Networks (SSN) suh as CCSA or SCAN (See Setion ) C4 C5 Used only for 2-point iruits C6-Used only for protetive relaying hannel (See Setions and ) C7 and C8 tjsed only for Eletroni Tandem Network (ETN) (See Setion ;, 5.02 The differenes between the Cl, C2, C4, and C5 grades of onditioning are the attenuation distortion and envelope delay distortion limits whih must be met in order to meet the requirements of FCC Tariff No All other parameters are the same for both basi and C-onditioning seleted. The parameter requirements are listed in Setion High Performane Data Conditioning (HPDC) 5.o3 An offering alled HPDC or D-type onditioning is available on interstate voiegrade analog data hannels. This onditioning provides more stringent ontrol over intermodulation distortion and signal-to-noise ratio than that on previously offered data hannels. These parameters are the ones most likely to affet high-speed voieband modems operating on analog hannels. 5.o4 High performane data onditioning (HPDC) is available in any one of three offerings. They are listed and defined as follows: (a) Type D1 HPDC is designed for a 2-point hannel not arranged for swithing where there is not more than one station per servie point (see Fig. 6). C2 (b) Type D2 HPDC is designed for a 3-point hannel equipped with entral offie (CO) w EI--EEI Fig. 6Type D 1 HPDC Ciruit Page 8

9 1SS 3, SECTION swithing arranged so that only two of the three stations may transmit to eah other at any given time as illustrated in Fig. 7 and 8. The ustomer master station (CMS) an ommuniate with ustomer station B or, when swithed, with ustomer station C. In no ase an ustomer stations B and C ommuniate with eah other. The CO swithing an be assigned to be ontrolled from any one of the three stations. A d ontrol hannel between the CO and the ontrol station is inluded in the offering if both the CO and the ontrol station are loated within the same rate enter (see Fig. 7). A separate series 1000 hannel must be provided to ontrol the swithing if the CO and the ontrol station are loated in different rate enters (see Fig. 8). In the examples shown in Fig. 7 and 8, the CMS is shown as the ontrol station. () Type D3 HPDC is designed for aess lines assoiated with AUTOVON networks, formally alled swithed iruits automati network (SCAN). Type D3 HPDC is disussed in Setion Restritions 5.05 The HPDC should be provided on Type 3002, 5032, 53~2, and 8302 voiegrade hannels. The HPDC may be provided on an alternate voie-data arrangement (if degraded voie performane due to removal of ompandors is aeptable to the ustomer). The option should not be provided on transfer arrangements, suh as alternate night use of PBX tie trunks, beause of degraded voie performane The HPDC equipped hannel maybe equipped with C-type onditioning if desired by the ustomer. CENTRAL CUSTOMER OFFICE A CONTROL J MASTER STATION *- - (STATION 1 A) SWITCH m L=_l OFFICE STATION I B B 1 OC CONTROL CHANNEL I CENTRAL CUSTOMER L OFFICE STATION Fig. 7Type D2 HPDC Ckuit With CO Swith in Same Rate Center as Control Station CENTRAL CUSTOMER STATION Hfi3!- L FF CE 3 i SERIES 1000 I I SW;CH I, CONTROL CHANNEL I CENTRAL CUSTOMER L OFFICE STATION Fig. 8Type D2 HPDC Ctruit With CO Swith Not in Same Rate Center as Control Station Page 9

10 SECTION o7 The HPDC will not be provided in loations where failities apable of supporting it (suh as, onsistent with the following faility onsiderations) are not available. Faility and Equipment Considerations 5.08 Ail failit~ seletion should be made by or urder the diretion of the iruit design engineer. The following information is inluded for ompleteness only and is not intended to imply that suh seletion or design onsiderations should be made in the field Careful seletion of failities is neessary in order to meet the strit C-nothed noise and intermodulation distortion requirements for HPDC iruits. LMX hannels and metalli failities are preferred. When a hoie of short-haul arrier systems is available, selet T arrier equipped with DID, D2, or D3 hannel banks If N2, N3, or ON arrier must be used, VF amplifiers will generally be required. Enhaned levels should be used on N2 hannels as speified in Setion N1 arrier and T arrier equipped with DIA or DIB hannel banks normally should not be used No more than three links of short-haul arrier (suh as N, ON, or T arrier) should be used. No more than two links of N or ON arrier should be used in the overall hannel. IVote: A link is defined as a faility terminated by a pair of hannel banks. S. 12 The use of nonompandored N or ON hannels will generally result in higher C-nothed noise levels than if ompandored hannel units are used. However, the ompandored hannel units have greater intermodulation distortion than the nonompandored hannel units, and this may be a greater problem than noise. In ases where the overall HPDC C-nothed noise requirements annot be met but the intermodulation distortion requirements an be easily met, it may be worthwhile to try ompandored hannel units as a means of improving the noise performane. The intermodulation distortion test must be repeated after making this equipment substitution to ensure that it is still within limits. S. 13 The faility C-nothed noise and intermodulation distortion requirements for T-arrier hannels and ompandored N- and ON-arrier hannels are given in Setion Nonompandored N and ON hannels that barely meet the noise requirements in Division 362 praties may not be satisfatory for HPDC iruits. The N and ON hannels whih meet a C-nothed noise requirement of 31 db or better will generally be satisfatory Where alternate voie is provided, mode signaling may be implemented using SF equipment. F-type equipment is preferred over E-type. The E3B and E4B signaling units should not be used beause they may ontribute an exessive amount of third-order intermodulation disorder. 6. CIRCUIT CONFIGURATIONS 6.01 The basi iruit onfigurations for PL data servie are as follows: (a) (b) 2-Point Multipoint () Central Offie Relay Swithed (d) Customer Premises Swithed. Combinations of these onfigurations may appear in a single PL iruit The point in 2-point and multipoint is defined to be one or more stations terminating a serving link (loal hannel). This is typially a single station on a long-haul iruit but may onsist of more than one data station, providing the loal distributing arrangement introdues negligible distortion to data and none of the stations requires more than 1500 feet of able from the distributing arrangement. This distributing arrangement may onsist of a bridging and/or a swithing arrangement. To meet the requirement of negligible distortion, a bridge in suh an appliation needs to be of the 2-wire resistive type that presents 600 ohms to all legs, In the ase of 4-wire, a separate 2-wire bridge is installed for eah diretion of transmission on the 4-wire iruit. Note: The failities on the two sides of a loal distributing arrangement are onsidered to be a part of the station equipment and are not onsidered as onstituting separate links. Page 10

11 1SS 3, SECTION If more than 1500 feet of able is required to onnet a station with the loal distributing arrangement, that station should be served by a separate end link from a CO bridge as shown in the lower portion of Fig. 9. Intraexhange iruits may be subjet to fewer restritions, depending on loal pratie. A~ <1500 * I X2 STA RIO- LINK w OAS STA <?500 * STA BRIDGE o 829 BRIDGE xl I-END 1 -+ *IF EXTENSIONS ARE OREATER THAN 1500 PROVIOE THE CIRCIJITAS A COBRIOGE AS SHOWN BELOW LIW. =l-+l- TA B. Multipoint Ctruits 6.04 These iruits may be basi or have Cl, C2, or C4 onditioning. If any part of a multipoint iruit is onditioned, all parts must be onditioned to the same degree. C4 onditioning on multipoint iruits is restrited to 3- or 4-point operation. An example of 4-point operation is given in Fig. 10 where only one station is shown for eah exhange. Station A is the master station and B, C, and D are remote stations. The grade of C4 onditioning an be speified between A and B, A and C, and A and D. No onditioning is speified between remote stations. Three-point operation is similar, with Station D omitted Figure 11 shows the maximum of four midlinks permitted with the basi or the Cl or C2 onditioned hannel. Note: The links between bridges in the same building are not onsidered middle links. These bridges should be eletrially as lose together as feasible and in no ase farther than 1500 feet of 22-gauge wire apart. C. Central OffIe Relay Swithed Ciruits 1 1 Pig. 9Ciruit Conversion of End Link to Midlink A. 2-Point Ciruits 6.o6 Figure 12 shows a onfiguration utilizing a maximum of three CO swithes that are allowed under the interstate tariff. The iruit may be unonditioned or have Cl or C2 onditioning between all pairs of stations Two-point iruits provide data ommuniation between two loations. These iruits may be basi or have Cl, C2, C4, or C5 onditioning. C5 onditioning an be ordered only on 2-point iruits. D. Customer Premises Swithed Ciruits 6.07 Figure 13 shows a ustomer premises swithed onnetion. This arrangement is permissible; however, no overall onditioning an be guaranteed. Page 11

12 SECTION SEALING CURRENT 7.01 Sealing urrent is low-level d applied to a able pair to break down a high resistane film whih may build up at nonsoldered hand-to-twisted splies. Continued appliation of this urrent sustains the normal resistane of the able pair The appliation of sealing urrent is a reommended maintenane ation as well as a preventive maintenane item. The following troubles an be resolved by the appliation of sealing urrent:. High d resistane, often more than 60 perent above normal High l-khz loss, often more than 50 perent (of the value in db) above normal. C-nothed noise, often more than 20 db above normal, and Unbalane in resistane of tip and ring ondutors. The reommended sealing urrent is 15 milliamps of ontinuous d preeded by 30 to 50 milliamps d for several seonds, ommonly referred to as,,zapi*. 2D o I r 1 o 7EQZR I 1 A E MASTER Q BRIOGE STATION o z o R CONDITIONING 13ETWEEN STATIONS g;, Iq+ :- OFFICE (MASTER) Pig. 104-Point Arrangement Page 2

13 1SS 3, SECTION E. L.~ o BR 10fX E,L. BRlw - E. L. - o #rk1., L w IT M.L, m., m.. mu, PZl -% BR 1 I-lo TI I I IT o H I I IYTI Co M. L, LEGEND n SERVING CENTRAL OFFICE o STATION.E. L. END LINK M.L. MIDDLE LINK E.L. I o E.L. 0 n P-u SWITCHING LOCATION BRIDGE LOCATION NOTE : NOT MORE THAN 5 UNITS OF SWITCHES AND ERID(XS NAY E3E TRANSITED FRO+4 ANY POINT TO ANY OTHIR POINT. (X4LY 3 SWITCHES ARE ALLUIJEO. Fig. 11 Cembined Centrsl Wle Swithed Multipeint Cwuit ENO o o o MID MID END E.L. E.L. EL. E.L. 0 0 E.L. E.L. 0 0 Fig. 12 Interstate Central Hte Relay Swithed Configuration Page 13

14 SECTION t o o 0 SKTION Division 311 DESCRIPTION Swithed Speial Servies System Data General AnalogTransmission Parameters Desription \.- 1 unspecified Data General Data Testing Priniples \ / CUSTOMER.- Swllli Data GeneralInteronnetion/ Interpositioning rservlhg CENTRAL OFFICE STATION Data GeneralData Servies Support Fig. 13Customer Swithing Arrangement 8. REFERENCES 8.01 The following douments provide additional desriptive information on failities and equipment assoiated with PL voieband data servie Voie Bandwidth Private Line Data CiruitsCiruit Conditioning Requirements Using the Collins CLA-Type System Voie Bandwidth Private Line Data Ciruits Maintenane PUBLICATION AT&T PIJB AT&T PUB AT&T PUB DESCRIPTION Data Communiations Using Voieband Private Line Channels Otober 1973 Analog Parameters Affeting Voieband Data Transmission Desription of Parameters July 1974 Transmission Parameters Affeting Voieband Data Transmission Measuring Tehniques January Voie Bandwidth Private Line Data CiruitsTests and Requirements Data Systems Common Ciruits, Equipment and Proedures Envelope Delay Charateristis of 200-Type Delay Equalizers Envelope Delay Charateristis of 384- and 385-Type Equalizers J99347 VF Amplitude and Delay Equalizing Equipment Desription SECTION DESCRIPTION A-Type Equalizer Desription Data Tehnial (DATEC) Support B-Type Equalizer Desription Swithed Servies Network Using Central Offie Swithing Mahine AUTOVON Servie Maintenane Division 310 Non-Swithed Speial Servies System B-Type Equalizer Presription Settings Data Systems Central Offie 406A Tone Generator Desription Page 14

15 1SS 3, SECTION SRCTION DESCRIPTION SECTION DESCRIPTION Metalli Faility Terminal Data Auxiliary Set 828C Amplitude and Delay Equalizer Desription and Operation (J99343SN) SD-1 C Desription and Installation Data Auxiliary Set 829-Type Channel Interfae Units Voieband Private Line Channels Desription Data Auxiliary Set 828A Speial Servies Protetion and Desription and Operation Safeguarding Page Pages