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9, Black Box ME375A-R2 10 ASYNC/SYNC 2-WIRE SHORT-HAUL MODEMS 2. Introduction The Async/Sync 2-Wire Short Haul Modem (A/S2W SHM) operates synchronously or asynchronously at high speeds (600 bps to 128 Kbps) and in full duplex over one pair of dedicated telephone lines. It has a range of 3.4 miles (5.5 km) over 26-AWG wire. The A/S2W SHM operates in full duplex over 2 wires by using the adaptive “echo-canceling” technique…
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31, 32 ASYNC/SYNC 2-WIRE SHORT-HAUL MODEMS ITU-TSS EIA Signal Name/ ITU-TSS Signal Name/ Description (CCITT) RS-232 Abbreviation for V.35 Abbreviation for V.24 Pin EIA RS-232 Pin(s) ITU-TSS V.35 Circuit (ME375) (ME375) (ME376) (ME376) 142 25 Test Mode (TM) KK Test Mode (TM) The A/S2W SHM raises this signal during any test and any time its internal BERT is activated (the PATT button is depressed).
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14, 15 CHAPTER 3: Installation Table 3-1. Possible Settings of Internal Controls (cont’d.) Callout Description Function/Label Possible Factory- No. in Settings Default Fig. 3-1 Setting 3 Clock-Source For master units, select INT INT (CLOCK) either internal timing (INT) EXT Jumper or external timing (EXT). LBT For slave units, always select loopback (received) timing (LBT). 4 Local Enable/disable control of DIS DIS Loopback local analog loopback EN (LLB) testing with signal…
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4, Black Box ME375A-R2 5 NOM STATEMENT 10. El equipo eléctrico deber ser situado fuera del alcance de fuentes de calor como radiadores, registros de calor, estufas u otros aparatos (incluyendo amplificadores) que producen calor. 11. El aparato eléctrico deberá ser connectado a una fuente de poder sólo del tipo descrito en el instructivo de operación, o como se indique en el aparato. 12. Precaución debe ser tomada de tal manera que la tierra fisica y …
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13, 14 ASYNC/SYNC 2-WIRE SHORT-HAUL MODEMS Table 3-1. Possible Settings of Internal Controls (cont’d.) Callout Description Position/Label Possible Factory- No. in Settings Default Fig. 3-1 Setting 2 Data-Rate Position 0 0.6K 0.6 Kbps Dial* Position 1 1.2K 1.2 Kbps Position 2 2.4K 2.4 Kbps Position 3 4.8K 4.8 Kbps Position 4 9.6K 9.6 Kbps Position 5 19.2K 19.2 Kbps Position 6 38.4K 38.4 Kbps Pos…
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26, 27 CHAPTER 5: Troubleshooting 5.1.3 L OCAL D IGITAL L OOPBACK This test is essentially the same as the Remote Digital Loopback test, but performed “in reverse,” so to speak. It allows you to make doubly sure of the line and the A/S2W SHMs’ line-side circuitry by setting up a loop in the opposite direction. Take these steps: 1. Push the local unit’s DIG (Local Digital Loopback) pushbutton. (There is no way to initiate this test electronically.) The TEST LED should lig…
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2, 3 FCC/IC RFI STATEMENTS, SAFETY WARNING FEDERAL COMMUNICATIONS COMMISSION AND CANADIAN DEPARTMENT OF COMMUNICATIONS 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 and found to comply with the l…
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29, 30 ASYNC/SYNC 2-WIRE SHORT-HAUL MODEMS ITU-TSS EIA Signal Name/ ITU-TSS Signal Name/ Description (CCITT) RS-232 Abbreviation for V.35 Abbreviation for V.24 Pin EIA RS-232 Pin(s) ITU-TSS V.35 Circuit (ME375) (ME375) (ME376) (ME376) 107 6 Data Set Ready (DSR) E Data Set Ready (DSR) If DIP Switch Position 7 is set to DSR, the A/S2W SHM holds this signal high unless it is in digital loopback or receives a remote-loopback signal from the remote unit. If DIP Swi…
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21, 22 ASYNC/SYNC 2-WIRE SHORT-HAUL MODEMS 4.2 Power-Up, Normal Operation, and Power-Down Making sure that you follow the guidelines in Section 3.4, power up the Async/Sync 2-Wire Short Haul Modem by plugging its AC power cord to an working AC outlet. (The unit has no power switch. To power it down, unplug it.) The PWR LED should light, indicating that the unit is on. If the local and remote A/S2W SHM units are both operating and transmitting data, the units’ fr…
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10, 11 CHAPTER 3: Installation 3. Installation This chapter tells you how to configure and install the Async/Sync 2-Wire Short Haul Modem. After you finish doing this, refer to Chapter 4 for operating information. 3.1 Placement The Async/Sync 2-Wire Short Haul Modem is designed to be placed on a tabletop, shelf, or bench, and is delivered completely assembled. (No provisions are made for bolting the A/S2W SHM to any surface.) The A/S2W SHM should be installed w…
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30, Black Box ME375A-R2 31 APPENDIX: Pinouts ITU-TSS EIA Signal Name/ ITU-TSS Signal Name/ Description (CCITT) RS-232 Abbreviation for V.35 Abbreviation for V.24 Pin EIA RS-232 Pin(s) ITU-TSS V.35 Circuit (ME375) (ME375) (ME376) (ME376) 114 15 Transmitter Signal Y Serial Clock Transmit A More commonly known as Element Timing [DCE] (SCT A) Transmit Clock (TXC). The (TSETC) AA Serial Clock Transmit B A/S2W SHM sends this (SCT B) data-rate clock si…
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1, CUSTOMER SUPPORT INFORMATION Order toll-free in the U.S. 24 hours, 7 A.M. Monday to midnight Friday: 877-877-BBOX FREE technical support, 24 hours a day, 7 days a week: Call 724-746-5500 or fax 724-746-0746 Mail order: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018 Web site: www.blackbox.com • E-mail: [email protected] MARCH 1998 ME375A-R2 ME375AE-R2 ME376A-R2 ME376AE-R2 Async/Sync 2-Wire Short Haul M…
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15, 16 ASYNC/SYNC 2-WIRE SHORT-HAUL MODEMS 3.3 Connecting the Data Cables To connect your data cables to the Async/Sync 2-Wire Short Haul Modem, take these steps, referring to Figure 3-2 below: 1. Connect the twisted-pair transmission line to the two clips marked LINE (or Pins 4 and 5 of the RJ-45 connector) and (optionally) the cable shield to the clip marked GND (or Pin 2 of the RJ-45 connector). If you are using the connecting t…
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28, ITU-TSS EIA Signal Name/ ITU-TSS Signal Name/ Description (CCITT) RS-232 Abbreviation for V.35 Abbreviation for V.24 Pin EIA RS-232 Pin(s) ITU-TSS V.35 Circuit (ME375) (ME375) (ME376) (ME376) 101 1 Protective Ground A Frame Ground (FGND) Chassis ground. May be (PGND) connected to or isolated from Signal Ground by setting the GROUND jumper. 102 7 Signal Ground (SGND) B Signal Ground (SGND) Signal ground. May be connected to or isolated from…
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27, 28 ASYNC/SYNC 2-WIRE SHORT-HAUL MODEMS 5.2 Calling Black Box If you determine that your Async/Sync 2-Wire Short Haul Modem is malfunctioning, do not attempt to alter or repair it. It contains no user-serviceable parts. Contact Black Box Technical Support at 724-746-5500; the problem might be solvable over the phone. Before you do, make a record of the history of the problem. We will be able to provide more efficient and accurate assistance if you have a complete description, in…
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12, Black Box ME375A-R2 13 CHAPTER 3: Installation Table 3-1. Possible Settings of Internal Controls Callout Description Position/Label Possible Factory- No. in Settings Default Fig. 3-1 Setting 1 DIP Switch Position 1 Async or sync Sync ON = ASYNC operation OFF = SYNC Position 2 8 or 7 data bits 8 bits ON = 8BIT OFF = 7BIT Position 3 Parity enabled Disabled ON = PRTY or disabled OFF = DIS Position 4 Even or odd Even ON = EVEN parity OFF = ODD Position 5 1 or 2 stop bits 1 bit ON = 1STB OFF = 2STB Positio…
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34, 1000 Park Drive • Lawrence, PA 15055-1018 • 724-746-5500 • Fax 724-746-0746 ©Copyright 1998. Black Box Corporation. All rights reserved.
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8, 9 CHAPTER 1: Specifications Fuse — ME375A-R2, ME376A-R2: 0.1-A slow-blow; ME375AE-R2, ME376AE-R2: 0.2-A slow-blow Other Power Protection — AC/DC overvoltage-protection circuits connected through transformers to transmit and receive leads on the line side, plus special gas diodes MTBF — 75,500 hours Maximum Altitude — 8000 ft. (2438.4 m) Temperature Tolerance — 32 to 122˚ F (0 to 50˚ C) Humidity Tolerance — Up to 90% noncondensing…
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7, 8 ASYNC/SYNC 2-WIRE SHORT-HAUL MODEMS User Controls — (5) Front-mounted: (4) Pushbuttons: DIG (local digital loopback), ANA (local analog loopback), REM (remote digital loopback), and PATT (test pattern); (1) Recessed RESET switch; (6) Internal: (1) 7-position DIP switch for protocol, data format, and signaling options; (1) Rotary switch for data rate; (4) Jumpers for clock source, loopback testing, and ground connection Diagnost…
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5, 6 ASYNC/SYNC 2-WIRE SHORT-HAUL MODEMS Contents Chapter Page 1. Specifications ............................................................................................. 7 2. Introduction ............................................................................................. 10 3. Installation ................................................................................................ 11…
