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Order toll-free in the U.S.: Call 877-877-BBOX (outside U.S. call 724-746-5500) SUPPORT FREE technical support 24 hours a day, 7 days a week: Call 724-746-5500 or fax 724-746-0746 INFORMATION Mailing address: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018 Web site: www.blackbox.com • E-mail: info@blackbox.com...
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LDM-144LR FEDERAL COMMUNICATIONS COMMISSION INDUSTRY CANADA RADIO FREQUENCY INTERFERENCE STATEMENTS This equipment generates, uses, and can radiate radio-frequency energy, and if not installed and used properly, that is, in strict accordance with the manufacturer’s instructions, may cause interference to radio communication. It has been tested...
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LDM-144LR NORMAS OFICIALES MEXICANAS (NOM) ELECTRICAL SAFETY STATEMENT INSTRUCCIONES DE SEGURIDAD 1. Todas las instrucciones de seguridad y operación deberán ser leídas antes de que el aparato eléctrico sea operado. 2. Las instrucciones de seguridad y operación deberán ser guardadas para referencia futura.
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LDM-144LR 12. Precaución debe ser tomada de tal manera que la tierra fisica y la polarización del equipo no sea eliminada. 13. Los cables de la fuente de poder deben ser guiados de tal manera que no sean pisados ni pellizcados por objetos colocados sobre o contra ellos, poniendo particular atención a los contactos y receptáculos donde salen del...
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LDM-144LR TRADEMARKS USED IN THIS MANUAL Any trademarks mentioned in this manual are acknowledged to be the property of the trademark owners.
LDM-144LR 1. Specifications 1.1 Transmission Line Line Type—Unloaded twisted pair 19 to 26 gauge; DC continuity is not required Range—Refer to Table 1-1 Level—0 dBm or -6 dBm (jumper-selectable) Transmit Impedance—LOW or HIGH (jumper-selectable) Receive Impedance—150 Ω or HIGH (jumper-selectable) Return Loss—Greater than 15 dB...
LDM-144LR Analog Loopback—Local (ANA): activated by front-panel pushbutton or by control signal from the digital interface Pattern—Test pattern (PATT): activated by a manual switch. The received pattern is compared to the transmitted pattern; if unequal, ERR LED flashes. NOTE The X.21 and G.703 interfaces do not support the activation of Digital and Analog loopbacks via the interface connector.
LDM-144LR 1.6 Physical Size—ME447AE: 1.75"H x 8.6"W x 10.6"D (4.4 x 21.5 x 26.5 cm); ME447C: 0.9"H x 6.2"W x 9"D (2.5 x 15.7 x 23 cm) Weight—ME447AE: 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%)
2.1 General The LDM-144LR is a short-range modem for synchronous transmission, full or half duplex, over unconditioned lines. The LDM-144LR has a range of up to 26.5 km (16.5 miles) and operates at selectable data rates from 48 kbps to 144 kbps.
2.2 Physical Description The LDM-144LR is available as a standalone unit (LDM-144LR), or as a rack- mounted unit (LDM-144LR Card) within a 19" rack. A 19" rack can carry up to 14 cards and provides DB25 connectivity to digital interfaces. Optional V.35 and X.21 interface adapters are available.
Timing DATA Recovery RATE Carrier Detect Figure 2-1. LDM-144LR Block Diagram. 2.3.1 E NCODER ODULATOR The Encoder Modulator receives data from the DTE and modulates it by means of the partial-response modulation technique. The Encoder Modulator can operate in one of the following modes: •...
RLB (J6) and the ALB (J5) jumpers respectively. When the LDM-144LR is used as a tail-end to a digital network, the V.54 DLY jumper (J7) in the modem closest to the network is set to ON to prevent other equipment from receiving the V.54 data...
26.4 16.5 25.2 15.7 15.2 10.5 14.5 21.6 14.6 20.4 14.2 12.3 19.2 11.5 11.2 10.8 16.8 10.5 10.1 2.4 Applications Figures 2-2 and 2-3 illustrate the LDM-144LR in a variety of configurations, each suitable for a particular application.
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LDM-144LR 4-wire Up to 26.4 km LDM-144LR LDM-144LR ASM-24 48-144 kbps ASM-24 Figure 2-2. Point-to-Point Configuration. ASM-24 RCV CLK V.54 DLY - Off X.21 Digital Service ASM-24 ASM-24 Network EXT CLK EXT CLK V.54 DLY - On V.54 DLY - On...
3.2 Site Preparation The LDM-144LR is installed within 5 ft. (1.5 m) of a grounded AC outlet and must be situated within 50 ft. (15 m) of the associated data terminal (for the V.35 model, the unit should be even closer to the terminal).
3.4.2 R ANEL ONNECTORS The rear panel connectors located on the LDM-144LR are shown in Figure 3-1. The connectors comprise the DTE interface connector and the line connector. The DTE interface is a field-changeable module and has a true-type connector. The line connector is a terminal block.
Figure 3-1. LDM-144LR Rear Panel Connectors. 3.4.3 DTE I NTERFACE The DTE side provides interfaces for input/output data, clock, and control signals between the LDM-144LR and the DTE. NOTE Detailed information on the DTE Interface Signal Assignments is given in Appendix B.
When the electrical installation has been completed and checked, determine the required configuration of the LDM-144LR and position the straps accordingly. The PCB strap locations of Figure 3-5 correspond to the numbers listed under “PCB Name”...
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LDM-144LR CD SENS RCV LVL RCV IMP HIGH HIGH BAUD RATE (kbps) XMT CLK XMT LEVEL XMT IMP CHASS HIGH SW. ENABLE CARR CNTRL 70 MS 8 MS RTS-CTS DLY Figure 3-2. LDM-144LR Switch and Jumper Settings.
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LDM-144LR Table 3-1. LDM-144LR Switch and Jumper Settings. Function Details Option Factory Name Setting XMT CLK Selects the transmit timing signal from either internal clock, external clock, or receive clock. SW, ENABLE When set to ON, enables SWITCH: ON activation of Diagnostics...
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LDM-144LR Table 3-1. LDM-144LR Switch and Jumper Settings (continued). Function Details Option Factory Name Setting V54 DLY When set to ON, the V.54 V54 DLY: ON is activated to prevent V54 DLY: OFF multiple loopback to tail-end circuits. RTS-CTS Selects the delay between DLY: 70 ms RTS and CTS.
LDM-144LR Table 3-1. LDM-144LR Switch and Jumper Settings (continued). Function Details Option Factory Name Setting BAUD RATE Selects the data rate in kbps 0-144 kbps (kbps) 1-128 kbps 2-112 kbps 3-96 kbps 4-72 kbps 5-64 kbps 64 kbps 6-56 kbps...
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LDM-144LR 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 the stripped end of the wire and remove the screwdriver.
OWERING To apply AC power: 1. Connect the AC power cable to the LDM-144LR mains socket and to an approved AC source. Check that the green PWR indicator is turned on. 2. If the local and remote LDM-144LR units are operational and passing...
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LDM-144LR Table 4-1. Indication States. Indicator State On or Flashing Flashing or Off Flashing or Off On or Flashing TEST 3. If the above indications are not obtained as a result of the initial powering up, verify that the three test pushbuttons, DIG, ANA and REM,...
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TEST Indicator, red When turned on, indicates that the LDM-144LR is set to one of the three loopback modes or that the internal BER test is activated. Indicator, yellow The ERR LED is active only when the internal BER tester is activated.
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LDM-144LR Table 4-2. Controls and Indicators (continued). Control When depressed, loops the local LDM-144LR receiver output back to its transmitter, as shown in Figure 5-3. The looped data is synchronized to the transmit clock. The DSR signal is set to the low state.
LDM-144LR 4.3.2 S In order to verify that the LDM-144LR is operating correctly, perform the internal BERT and analog loopback tests detailed in Section 5-2 and Section 5-3 respectively. 4.3.3 O PERATION With the exception of occasional monitoring of indicators, the LDM-144LR is operated unattended.
• The loopbacks can be activated by either the front-panel push buttons or by control signal from the digital interface. • The LDM-144LR has a built in BER tester and pattern generator which can be activated via the front panel switches.
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LDM-144LR. After completion of the test (or when the fault has been corrected), de-activate the ANA loopback test.
(CARR), is set to ON or that the RTS signal is high. • Press the PATT pushbutton and check the following indications: - If the ERR indicator remains turned on or blinks, then the LDM-144LR is faulty; replace it. - If the indications are as specified in step 3 above, restore the push-buttons...
OOPBACK The Local digital loopback (DIG) consists of looping the received data back to the remote LDM-144LR, as shown in Figure 5-3. Using this test, the operator at the remote end can determine the performance of the local and remote LDM-144LR units, and the communication lines interconnecting them.
The RM110A consists of one or two power supplies and up to 14 plug-in cards. The card types can be LDM-144LR or other modem cards, (any mix of up to 14 plug-in cards). The rear panel consists of a snap connector and a DB25 D-type connector.
The indicator LEDs show activity when the AC power supply is connected to the mains plug, and the 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.
ECHANICAL NSTALLATION After installing the RM110A in the 19" rack, the LDM-144LR cards should be inserted into it. Once the cards have been inserted, the nut on the top and bottom of each card should be tightened to ensure that it is fully inserted into...
LDM-144LR 6.5 Operation 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.
LDM-144LR Appendix A: IR-G.703 Co-Directional 64-kbps Interface IR-G.703 Co-Directional Interface The IR-G.703 is an interface module for modems, converting G.703 co- directional signals to TTL levels. The converted data is sent over the modem link using the modem’s modulation technique and is converted back at the other end into G.703 64-kbps co-directional signals, or any other possible...
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LDM-144LR (9,11) RCV RCV (3,6) (2,16) XMT (4,5) (7) GND Line Fuse GND RCV RCV GND -230V / 0.1A T 250V Terminal Block (Standalone) DB25 RJ-45 (Rack Version) (Standalone) Figure A-1. IR G.703 Connector Options. The G.703 interface module has two operation modes, TX-FIFO and RX-FIFO, which are strap-selectable on the board (see Figure A-2).
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LDM-144LR A: TX-FIFO This mode is used in tail-end applications of G.703 co-directional networks. In this application, system timing is provided by the G.703 network. The IR- G.703 module has an internal buffer to compensate for the phase delay introduced to the system by the line delay occurring between the two modems.
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LDM-144LR B: RX-FIFO This mode is used in applications where the G.703 co-directional 64-kbps side recovers the clock from the modem link. This mode is used mainly when the attached equipment has a G.703 co-directional interface, but no ability to produce clock.
LDM-144LR Appendix C: Unit Case Assembly Installation of the Unit Case into a 19" Rack ENERAL The height of the unit is 1U (1.75"); the width of the unit is slightly less than half the available mounting width. Rack adapter kits, RM516-RM523, are available for installing either a single unit or two units side by side in the 19"...
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LDM-144LR Figure D-1. Installation of a Single Unit. NSTALLATION OF NITS Rack-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 two units in the 19"...
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LDM-144LR Two-unit installation instructions 1. Fasten one long side rail to each unit (one to the right side of one unit, the other to the left side of the other unit) using the four screws and flatwashers supplied. The side rails must be attached in opposing fashion, the narrow flange of the first rail opposite the wide flange of the second rail.
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