METALLIC FACILITY TERMINAL LOOP-START AND GROUND-START TO DX OR E&M SIGNALING CONVERTERS (J99343FA, FB, FC, AND FD)

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BELL SYSTEM PRACTCES AT&TCo Standard ssue 1, November 1979 METALLC FACLTY TERMNAL LOOPSTART AND GROUNDSTART TO DX OR E&M SGNALNG CONVERTERS (J99343FA, FB, FC, AND FD) NSTALLATON AND TESTNG,. CONTENTS PAGE CONTENTS PAGE 1. GENERAL........... 1 1. Toll Diversion Option Switch (J99343FC)............., w. CHARACTERSTCS OF THE LOOPSTART AND GROUNDSTART TO DUPLEX OR E&M SGNALNG UNTS J99343FA, FB, FC, AND FD........... J. Toll Diversion Option Switch (J99343FD)............. 4. APPLCATONS......... A. General.......... 5. MANTENANCE AND TESTS..... 7 B. J99343FA Signaling Unit.... A. Maintenance........ 7 C. J99343FB Signaling Unit.... B. Tests........... 7 D. J99343FC Signaling Unit..... REFERENCES.......... 8 E. J99343FD Signaling Unit.... 3. SWTCH FUNCTONS AND SETTNGS. A. General.......... B. Midpoint Capacitor (MPC) Switch. c. DX/E&M and ML1 & ML Switches, DX Mode......... D. Balance Switches....... 3 4 4 4 4 1. GENERAL 1.01 The metallic facility terminal (MFT) is composed of shelving arrangements which accept transmission and signaling plugin units that are electrically compatible with the MFT. These units are a standard size which fit the MFT shelving slots. This section describes the installation and testing procedures for the J99343FA, FB, FC, and FD loopstart and groundstart to duplex or E&M MFT signaling units. E. DX/E&M and ML1 & ML Switchesr E& M Mode........ 1.0 Whenever this section is reissued, the reason(s) for reissue will be given in this paragraph. F. G. H. BOR Switch (J99343FA and FC). MReversing Switch (J99343FA). EReversing Switch (J99343FB).. 1.03 The J99343FA, FB, FC, and FD signaling units provide all the features and options of a number of older dial long line (DLL) signaling circuits. Although similar in function, the new units incorporate modern circuit designs and NOTCE Not for use or disclosure outside the Bell System except under written agreement Printed in U.S.A. Page 1

_ components for improved reliability and performance when used with the MFT transmission units. Options may be selected by switches instead of wire straps. 1.04 Additional detailed information and complete schematic diagrams of the J99343FA, FB, FC, and FD are contained in CP34 through CP37, respectively, of SD1 C35901. The J99343FA,L is contained in CP49 of SD1 C35901.. CHARACTERSTCS OF THE LOOPSTART AND GROUNDSTART TO DUPLEX OR E&M SGNALNG UNTS J99343FA, FB, FC, AND FD A. General.o1 The FA, FB, FC, and FD series of signaling units provide signal range extension and conversion for loopstart or groundstart applications. The FA (central office [CO] or PBX end) and FB (station end) units are companion units used for loopstart lines, while the FC (CO end) and FD (PBX end) units are companion units used for groundstart trunks. Range information may be found in Table A. Additional descriptive information may be found in Section 33911105. Note: Although the J99343FA, FB/FC and FD are companion units, the units are compatible (individually) with other applications, such as with older DLL systems (see crossreference list of Section 3391105). detector design. This new design provides the capability of detecting distinctive ringing with increased reliability and immunity to longitudinal noise. t functionally replaces the FA,L1 and LA, which will be rated manufacture discontinued..04 Table B lists input and output signals of the J99343FA signaling unit for all circuit conditions when operating in the E&M mode. C. J99343FB Signaling Unit.05 The FB unit is a duplex or E&M to loopstart converter (DX/EMLS). t serves as the station end signaling unit when used in conjunction with the FA. Features of the FB unit include: (1) () (3) (4) Selectable E&M or duplex detection Regenerative ringing Ring tripping detection nversion of the Elead for use with carrier..0 Table B lists input and output signals of the J99343FB signaling unit for all circuit conditions when operating in the E&M signaling mode... *, B. J99343FA Signaling Unit.0 The FA unit is a loopstart to duplex or E&M converter (LSDX/EM). t serves as the switch end signaling unit in conjunction with the FB unit at the station end. Features of the FA unit include: (1) Selectable E&M or duplex output () Pulse correction 58 percent break (3) 0 to 30Hz ringing detection (4) MLead polarity reversal for carrier applications..03 The FA,LA is a modified version of the FA,L1 unit which provides the additional capability of detecting short ringing signals (ie, distinctive ringing), such as those produced by the CSS01 PBX. The FA,L offers a new ringing D. J99343FC Signaling Unit.07 The FC unit is a groundstart to duplex or E&M converter (GSDX/EM). t serves as the switch end signaling unit in conjunction with an FD unit at the station end. Features of the FC unit include: (1) Selectable E&M or duplex output () Pulse correction 58 percent break (3) 0 to 30Hz ringing detection (4) Reverse battery detector (toll diversion)..08 Table C lists input and output signals of the J99343FC signaling unit for all circuit conditions when operating in the E&M signaling mode. w u Page

. 1SS 1, TABLE A MAXlhWM S13NALNG RANGES (OiMS) J99343FA, FB, FC, AND FD (NOTE) A. Station Side of J99343FB and FD Converters: 1. Supervision and Dial Pulsing* a. 48V @ 1 m Adc 770 @ 3 m Adc 185 b. 7V @ 1 m Adc 470 @ 3 m Adc 870. 8V rms 0Hz Ringing Range With 50V rms Across: a. Ringers Stiff Notch 880 b. 3 Ringers Stiff Notch 180 3. Ring Trip Range With a 48V dc Trip Supply 4400 B. Switching Side of J99343FA and FC Converters: 1. Total Resistance to be subtracted from the CO Supervisory Range: J99343FA J99343FC a. Build Out resistors OUT o 15 b. BOR N 511 511 c. Toll Diversion Detector N N/A 5. GroundStart Detection Range Greater than 350 3. Ringing Dectector Range With an 8V rms 0 Hz or 15V rms 30 Hz nput Greater than 350 C. DX Signal Detection Range on Metallic Facilities of Gauges From 19 to, 5000 Loaded or Nonloaded, All Units t L D. E Lead Signal Detection Range, All Units 00 Note: The range values listed are the maximum range external to the signaling converter and do not take into account the reduction in range which is caused by resistance in the companion transmission unit. To determine the exact range of a signaling converter when used with a specific MFT transmission unit, refer to the appropriate LSR range information. *These range values are for the nominal supply voltage indicated. Variations in the supply voltage will result in a corresponding variation in range. E. J99343FD Signaling Unit () Regenerative ringing +.09 The FD unit is a duplex or E&M to groundstart (3) converter (DX/EMGS). t serves as the station end signaling unit when used in conjunction (4) with the FC. Features of the FD unit include: %100 (1) Selectable E&M or duplex detection in the.10 Ring tripping Battery reversal (toll diversion). Table C lists input and output signals of the J99343FD signaling unit when operating E&M mode. Page 3

TABLE LOOPSTART E&M AND LooPED E&M slgnalng LEAD STATES (NOTE 1) B e J99343FA (CO END) LEADS E&M co co E&M STA STA STA DAL LEADS TYPE DLE RNGNG TYPE ONHOOK OFFHOOK PULSNG OUTPUTS NPUTS (NOTE ) M* GRD BATT E Oc GRD M/SB Oc c E/SG Oc c OC/GRD w.. NPUTS (NOTE ) OUTPUTS i J99343FB (STA END) E* Oc GRD M GRD BATT E/SG Oc c M/SB Oc c BATT/GRD 4 Note 1: 13ATT Battery GRD Ground Oc Open Circuit: Type Referenced to ground Type Between E and SG leads and between M and SB leads c Closure between E and SG leads and between M and SB leads in ~pe interfaces. Note : The input signals originate in (external) connecting circuits. The signaling states indicated are received by the E lead of the converter. * An option switch on the J99343FA allows the GRD/BATT signaling states of the M lead to be interchanged. An option switch on the J99343FB allows the OC/GRD signaling states of the E lead to be interchanged. The signaling states shown in the table are with the option switches set in the NOR position. 3. SWTCH FUNCTONS AND SETTNGS A. General 3.01 Switch settings in the following paragraphs apply to the FA, FB, FC, and FD except where noted otherwise. The MPC switch should be down for all 4wire applications and for any wire applications when there is ~F or less midpoint capacitance in the associated transmission unit. C. DX/E&M and ML1 & ML Switches, DX Mode B. Midpoint Capacitor (MPC) Switch 3.0 The MPC switch allows insertion of a 4KF capacitor across the input of the DX detector. 3.o3 For DX mode, the DX/E&M switch should be set in the DX position. The ML1 & ML switches should be down. Page 4

( ( TABLE C GROUNDSTART E&M AND LOOPED E&M SGNALNG LEAD STATES (NOTE 1) CO RNGNG E&M LEADS co CO TP GRD (AT END TYPE DLE (GS SEZURE) OF CYCLE) (TOLL CO BATT REV DVERSON) LEADS E&M TYPE PBX ONHOOK PBX RNG GRD (GS SEZURE) PBX DAL PULSNG OUTPUTS NPUTS (NOTE ),J99343FC (CO END) BATT/ BATT/ M GRD BATT GRD GRD M/SB H OC c E Oc E/SG Oc T c J99343FD (PBX END) NPUTS (NOTE ) GRD/ GRD/ E Oc GRD Oc Oc E/SG Oc c OUTPUTS BATT/ M J GRD BATT GRD M/SB Oc c PULDES Note 1: BATT Battery GRD Ground Oc Open Circuit: Type Referenced to ground fipe Between E andsg leads and between M and SB leads c Closure between E and SG leads and between M and SB leads in type interfaces. Note : The input signajs originate in (external) connecting circuits. The signaling states indicated are received by the E lead of the converter.

D. Balance Switches 3.o4 To obtain a balancing resistance equal to the loop resistance, the R BAL screw switches are set as follows: R BAL DESG SWTCH SETTNG K UP K UP lk UP 500 UP 50 UP OHMS ADDED TO BALANCNG RESSTANCE 000 000 1000 500 50 3.05 To obtain the desired balancing capacitance, the C BAL screw switches are set as follows: C BAL SWTCH HF ADDED TO DESG SETTNG BALANCE CAPACTANCE G. MReversing Switch (J99343FA) 3.08 The Mlead reversing switch (MRV) should be set to NOR to have the M lead grounded when the circuit is idle or in the talk state and should be set to REV to have the M lead at battery potential when the circuit is idle or in the talk state. The REV position is used in conjunction with certain carrier systems to reverse the phasing of batteryjground connections on the Mrelay contacts. H. EReversing Switch (J99343FB) 3.o9 The Elead reversing switch (ERV) should be set to NOR to have the E lead open when the circuit is idle and to REV to have the E lead grounded when the circuit is idle. The REV position is used in conjunction with certain carrier systems to invert the facility input signals. 1. Toll Diversion Option Switch (J99343FC).. * 1 DOWN 1 DOWN 4 DOWN 4 E. DX/E&M and ML1 & ML Switches, E&M Mode 3.0 For E&M mode, DX1 E&M selector switch should be set in the E&M position and all capacitor screw switches (MPC, 1, and 4) should be turned up and all resistor switches (K, K, lk, 500 and 50) should be turned down. To provide a Type (with E&M leads) E&M interface, screw switches ML1 & ML should be turned down, and to provide a Type (looped E&M with E, M, SB, and SG leads) interface, screw switches ML1 & ML should be turned up. F. BOR Switch (J99343FA and FC) 3.o7 The buildout resistor switch (BOR) adds 511 ohms to the switching side circuit resistance and should be set as follows: BOR Switch Conductor Loop Resistance Switching Side (Ohms) UP Less than 00 DOWN Greater than 00 3.10 The toll diversion options screw (TS) switch should be up to allow the converter to pass toll diversion signals. t should be down to inhibit the toll diversion feature. _. J. Toll Diversion Option Switch (J99343FD) 3.11 The toll diversion option screw (TS) switch should be down to allow the converter to pass toll diversion signals. t should be up to inhibit the toll diversion feature. 4. APPLCATONS 4.o1 The J99343FA and FB signaling units are _ intended for use on long special services circuits such as offpremises extensions, wide area v telecommunication service lines, and lway PBXCO trunks. They operate loopstart and are switchselectable. for either E&M or DX signaling modes. 4.0 The J99343FC and FD signaling units are companion signaling converter units intended _, for providing signaling range extension on way PBXCO groundstart trunks and FX trunks. The PBXCO trunks can include toll diversion. Both units contain switches for operation in either E&M or DX signaling modes. Page

1SS 1, 4.o3 Typical circuit applications for these converters are shown in Fig. 1. The diagram in Fig. 1A shows the signaling lead interfaces between the transmission and signaling units when used with metallic facilities. Figure lb shows the signaling connections required between the transmission unit, signaling unit, and carrier signaling circuit.. 5. MANTENANCE AND TESTS of the defective unit with a good spare unit. Location of the defective unit may be determined by end to end tests (see subpart B). The defective unit should be returned to the nearest Western Electric Service Center for repair. Note: t is assumed signaling options and/or settings have been adjusted per circuit requirements before testing.. A. Maintenance, 5.01 When there is a malfunction in a signaling circuit(s) due to a defective signaling unit, the signaling quality is maintained by replacement B. Tests 5.0 When a circuit contains several signaling links, an end to end test may not locate a co. PBX OR 51A / \ / \ TU TU J A,B A,B A,B A,B J99343FA * OR J99343FC+ J99343FB * OR J99343FO+ A. METALLC FACLTY Co, PBX OR STA TU l,r CARRER AS 1. AS SG 1 CKT. CARRER SG.! T1, R1 AS 1, AS * TU A,B E,fl E,tl A,B J99343FA * OT? J99343FC+ SB, SG SB, SG J99343FB * OR J9B343FO+ B. CARRER FACLTY * LOOP START TO ESM OR OX + GROUNO START TO Efl OR OX Fig. 1 Metallic and Carrier Applications of the J99343FA, FB, FC, FD Signaling Converters Page 7

defective signaling unit. Further tests may be conducted to sectionalize the trouble. wire intermediate repeaters Section 339115 5.o3 The J99343FA, FB, FC, and FD MFT signaling units cannot be field tested individually. They must be tested through the companion MFT transmission unit which requires the use of the J99343TB test extender (Section 3391010). The test extender, which is designed to allow adjustment and testing of MFT transmission units, provides jack access to the AS1, AS, and A&B or SX signaling leads which pass through the transmission unit (TU). Opens and closures of the loop or pulses of the signaling units may be checked with the appropriate test equipment using the test jacks provided by the test extender. Figure 1 shows the lead designations for various types of switching offices. 4 or 4 wire intermediate repeaters Section 33911 44 wire repeaters Section 339134 4 wire terminal repeaters Section 339135. REFERENCES.01 The following references contain additional information which may be helpful. e, Caution: To prevent service interruptions, working circuits should be turned down before removing a transmission unit for tests. Note: Only units designed to work in the transmission unit slot of MFT bays should be plugged into the test extender mounting, ie, the J99343FA FB, FC, and FD unit lead arrangements are not compatible with the TU lead arrangement and no attempt should be made to plug these units directly into the test extender. 5.o4 n the event an MFT repeater is suspected of causing a malfunction, test procedures of the following sections should be consulted: REFERENCE TTLE 33910100 General Description of MFT 3391010 MFT Test Extender Description and Operation 33910180 General Application nformation for MFT CD1 C35901 Common Systems Metallic Facility Terminal Circuit SD1 C4850 Common Systems Test Extender for Use With Metallic Facility Terminal d wire terminal repeaters Section 339114 SDC35901 Metallic Facility Terminal Circuit Page 8 8 Pages