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14

LDM-144LR

Table 2-1.  Typical Range.

Data Rate 19AWG (0.9 mm) 22 AWG (0.6 mm) 24 AWG (0.5 mm) 26 AWG (0.4 mm)

(kbps)

km

miles

km

miles

km

miles

km

miles

48

26.4

16.5

16

10

11

6.8

8

5

56

25.2

15.7

15.2

9.5

10.5

6.5

7.5

4.5

64

24

15

14.5

9

10

6.2

7.3

4.7

72

21.6

14.6

13

8.1

9

7

7

4.6

96

20.4

14.2

12.3

7.7

8.5

5.3

6.8

4.5

112

19.2

12

11.5

7.2

8

4.9

5.7

3.4

128

18

11.2

10.8

6.8

7.5

4.7

5

3.3

144

16.8

10.5

10.1

6.4

7

4.3

4.8

3.2

2.4  Applications

Figures 2-2 

and 

2-3

illustrate the LDM-144LR in a variety of configurations,

each suitable for a particular application.

Содержание LDM-144LR

Страница 1: ...hours a day 7 days a week Call 724 746 5500 or fax 724 746 0746 Mailing address Black Box Corporation 1000 Park Drive Lawrence PA 15055 1018 Web site www blackbox com E mail info blackbox com MARCH 19...

Страница 2: ...ated in a commercial environment Operation of this equipment in a residential area is likely to cause interference in which case the user at his own expense will be required to take whatever measures...

Страница 3: ...o el ctrico debe ser montado a la pared o al techo s lo como sea recomendado por el fabricante 8 Servicio El usuario no debe intentar dar servicio al equipo el ctrico m s all a lo descrito en las inst...

Страница 4: ...una antena externa deber ser localizada lejos de las lineas de energia 16 El cable de corriente deber ser desconectado del cuando el equipo no sea usado por un largo periodo de tiempo 17 Cuidado debe...

Страница 5: ...4 LDM 144LR TRADEMARKS USED IN THIS MANUAL Any trademarks mentioned in this manual are acknowledged to be the property of the trademark owners...

Страница 6: ...1 Encoder Modulator 12 2 3 2 Modulation Timing 12 2 3 3 Selectable Level Transmit Amplifier 13 2 3 4 V 54 Diagnostics 13 2 3 5 Test Pattern Generator and Receiver 13 2 3 6 Selectable Carrier Detect S...

Страница 7: ...1 Local Test Local Analog Loopback ANA 30 5 2 2 Remote Digital Loopback REM 32 5 2 3 Local Digital Loopback DIG 33 6 Card Cage Version 34 6 1 RM110A Description 34 6 2 LDM 144LR Card Version 35 6 3 Po...

Страница 8: ...ulation Partial Response Class IV PR4 1 2 Digital Interface Type When ordering three options are available 1 V 24 RS 232 via a DB25 female connector ME447C 232 2 V 35 via a 34 pin female connector ME4...

Страница 9: ...via the interface connector 1 4 Timing Elements Receive Clock Derived from the Receive signal Transmit Clock Derived from one of three alternative sources 1 External oscillator 2 External from the DTE...

Страница 10: ...E 2 6 lb 1 2 kg ME447C 10 oz 0 36 kg 1 7 Electrical Power Supply 100 VAC 115 VAC or 230 VAC 10 47 to 63 Hz 5 watts 48 VDC 10 1 8 Protection AC DC overvoltage protection circuits are connected in line...

Страница 11: ...transformers which in conjunction with protective circuitry safeguard against AC or DC overvoltages The protective circuitry enables operation even when DC is connected to the line The LDM 144LR trans...

Страница 12: ...end to end connectivity When a bit error is encountered the ERR indicator flashes 2 2 Physical Description The LDM 144LR is available as a standalone unit LDM 144LR or as a rack mounted unit LDM 144L...

Страница 13: ...odem s internal crystal oscillator INT The DTE clock EXT The receive signal recovered clock RCV Setting the transmit clock jumper J1 determines the timing mode of the LDM 144LR CTS Delay OSC Power Sup...

Страница 14: ...pment from receiving the V 54 data sequence and inducing it into the loop 2 3 5 TEST PATTERN GENERATOR AND RECEIVER The Test Pattern Generator enables easy and quick testing of the local modem and the...

Страница 15: ...5 2 15 7 15 2 9 5 10 5 6 5 7 5 4 5 64 24 15 14 5 9 10 6 2 7 3 4 7 72 21 6 14 6 13 8 1 9 7 7 4 6 96 20 4 14 2 12 3 7 7 8 5 5 3 6 8 4 5 112 19 2 12 11 5 7 2 8 4 9 5 7 3 4 128 18 11 2 10 8 6 8 7 5 4 7 5...

Страница 16: ...on Figure 2 3 X 21 Digital Network Tail end ASM 24 RCV CLK V 54 DLY Off EXT CLK V 54 DLY On EXT CLK V 54 DLY On RCV CLK V 54 DLY Off ASM 24 ASM 24 ASM 24 X 21 Digital Service Network ASM 24 ASM 24 4 w...

Страница 17: ...ft 15 m of the associated data terminal for the V 35 model the unit should be even closer to the terminal Allow at least 36 in 90 cm of frontal clearance for accessibility during operations and mainte...

Страница 18: ...s located in an integral type fuse holder located on the rear panel as shown in Figure 3 1 Make sure that only fuses of the required rating as marked on the rear panel are used for replacement Do not...

Страница 19: ...the LDM 144LR and the DTE NOTE Detailed information on the DTE Interface Signal Assignments is given in Appendix B V 24 RS 232 The V 24 RS 232 interface connector D type has a standard 25 pin pinout c...

Страница 20: ...correspond to the numbers listed under PCB Name in Table 3 1 WARNING Disconnect the AC power cord before removing the unit s cover Installation operation and maintenance should be performed by an expe...

Страница 21: ...BAUD RATE kbps XMT CLK RCV INT EXT CARR LOW HIGH CD SENS A L B EN DIS R L B J1 J4 SW1 J2 J3 J5 J6 0 dBm 6 XMT IMP XMT LEVEL HIGH LOW J12 J11 J13 CHASS DIS CON RTS CTS DLY 70 MS 8 MS J8 V54 DLY DTE CO...

Страница 22: ...s SWITCH OFF through the front panel pushbuttons J3 CARR When set to ON the transmit CARR ON ON carrier is permanently CARR CNTRL activated J4 CD SENS Controls Carrier detect CD SENS LOW sensitivity l...

Страница 23: ...LVL 0 dBm 0 dBm modem 0 dBm for ranges RCV LVL 6 dBm up to the product limitation 6 dBm for short ranges J10 RCV IMP Selects the receive line RCV IMP 150 150 impedance RCV IMP HIGH J11 XMT LEVEL Selec...

Страница 24: ...nsmit Timing XMT CLK of one unit to the receive clock RCV and the other unit to either internal INT or external EXT clock 3 4 6 LINE SIDE The terminal block provides four connecting points to the tran...

Страница 25: ...ND Wire Insertion Details 1 Insert screwdriver into square hole 2 Raise inserted screwdriver putting pressure on the ramp within the square hole The wire clamp within the round hole will open 3 Insert...

Страница 26: ...ndicator functions are described in Table 4 2 4 3 Operating Procedure NOTE When the unit power is turned on operating personnel are exposed to voltages below 30 volts on the card or any accessible are...

Страница 27: ...PWR On RTS On or Flashing TD Flashing or Off RD Flashing or Off DCD On or Flashing TEST Off ERR Off 3 If the above indications are not obtained as a result of the initial powering up verify that the...

Страница 28: ...tor flickers RD Indicator yellow When turned on indicates that a steady space is being received When data is received the indicator flickers DCD Indicator yellow When turned on indicates a valid recei...

Страница 29: ...opback may also be activated from the DTE when DTE Command ALB jumper is set to EN REM Control When depressed loops the remote LDM 144LR receiver output back to its transmitter as shown in Figure 5 2...

Страница 30: ...ve the AC power cable from the AC source 4 4 Field Settings of Jumpers and Switches WARNING Disconnect the AC power cord before removing the unit s cover Installation operation and maintenance of the...

Страница 31: ...etween the modems Use the test procedures provided in this chapter to verify normal system operation and to isolate faulty equipment in the event of failure NOTE Before testing the operation of the da...

Страница 32: ...f the methods described below Using the DTE and checking the echoed data stream Using an external Bit Error Rate Tester BERT unit 4 Perform Step 3 above at both ends If the BERT test indicates correct...

Страница 33: ...3 and 4 3 If step 2 indicates a fault while the local analog loopback test described in Section 5 2 1 was successful for both the local and remote modems then the line or the line circuits of the loc...

Страница 34: ...determine the performance of the local and remote LDM 144LR units and the communication lines interconnecting them Figure 5 3 Local LDM 144LR in Digital Loopback RCVR XMTR LOCAL DATA TERMINAL RCVR XM...

Страница 35: ...lines The transmit pair is connected to the terminals marked XMT the receive pair is connected to the terminals marked RCV and an optional ground connection is the fifth screw The interface connector...

Страница 36: ...switch is on Each LDM 144LR Card has two fuses which protect the entire system against power failure in the event of a short circuit in one of the cards 6 3 2 DC SUPPLY 48 VDC The power supply accepts...

Страница 37: ...in Section 3 4 5 The rear panel is shown in Figure 6 3 6 4 2 MECHANICAL INSTALLATION After installing the RM110A in the 19 rack the LDM 144LR cards should be inserted into it Once the cards have been...

Страница 38: ...peration The power supply is controlled from the power module on the left hand side of the rear panel of the RM110A see Figure 6 3 Figure 6 3 RM110A Rear Panel M14 M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M11 M...

Страница 39: ...m and is available with two types of physical connections terminal block or RJ 45 The rack version mounts on the rack version modem card and uses the modem s edge connector for communication The edge...

Страница 40: ...ap selectable on the board see Figure A 2 Figure A 2 Strap Selectable Operation Modes TX FIFO RX FIFO Terminal Block or RJ 45 in the Stand alone version RCV 3 6 4 5 XMT 1 8 9 11 RCV 2 16 XMT 7 GND DTE...

Страница 41: ...ate for the phase delay introduced to the system by the line delay occurring between the two modems The buffer is a 2 bit FIFO buffer and is connected as shown in Figure A 3 Figure A 3 TX FIFO Block D...

Страница 42: ...4 illustrates the buffer connection and the required application set up Other clock modes are available in addition to the one shown in Figure A 4 The only restriction is that the clock source must be...

Страница 43: ...e Connector Pin Circuit Pin Circuit Protective Ground 1 Shield 1 Signal Ground 19 37 20 7 AB Transmitted Data 4 SD A 2 BA A 22 SD B 14 BA B Received Data 6 RD A 3 BB A 24 RD B 16 BB B Request to Send...

Страница 44: ...44LR 37 Pin Connector SD DB25 Female Connector Pin Circuit Pin Circuit External Transmit 17 TT A 24 DA A Clock 35 TT B 11 DA B Transmit Clock 5 ST A 15 DB A 23 ST B 12 DB B Receive Clock 8 RT A 17 DD...

Страница 45: ...A SINGLE UNIT Rack adapter components for installing a single unit include one short bracket and one long bracket Each bracket is fastened to the side walls of the unit by two screws which are insert...

Страница 46: ...k adapter components for installing two units include two long side rails one for each unit which slide one into the other fastening the two units together and two short side brackets which hold the t...

Страница 47: ...il 2 Attach one short bracket opposite the side rail on each unit using the four screws supplied 3 Slide the side rail of one unit into the side rail of the other unit fastening the two units together...

Страница 48: ...1000 Park Drive Lawrence PA 15055 1018 724 746 5500 Fax 724 746 0746 Copyright 1997 Black Box Corporation All rights reserved...

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