Black Box ME475A User Manual

BLACK BOX
TD RD CDRTS ERROR TEST
Async/Sync Short Haul Modem
511 -
511E -
Remote
Normal
Local
SPECIFICATIONS:
Transmission Format: Synchronous or Asynchronous, 2-wire/half duplex or 4-wire/full or half duplex.
Interface: RS-232 (CCITT V.24) connection via DB25 female; Twisted-pair connection via RJ-45 or
terminal block.
Transmission Line: 2- or 4-wire UTP, 19 to 26 AWG.
Data Rates: Synchronous or Asynchronous at 1.2, 1.8, 2.4, 3.6, 4.8, 7.2, 9.6, 14.4, 19.2, 28.8, 38.4, 57.6,
(Switch-selectable)
Clocking: Internal, External, or Receive Recover.
Controls: Carrier Constantly ON or Controlled by RTS; RTS/CTS delay set to no delay, 7 ms, or 53 ms.
Applications: Point-to-Point or Multipoint.
Indicators: Bcolor LED's for TD, RD, RTS, and CD; Single LED's for Test, and Error.
RTS Anti-Stream Timer: 12.5 sec., 50 sec., or disabled (switch-selectable); Tolerance: +50%, -0.
Diagnostics: V.52-compliant bit-error-rate pattern (511/511E pattern) generator and detector with
error-injection mode; V.54 compliant--Local Analog Loopback and Remote Digital Loopback,
activated by front-panel switch or via RS-232 interface.
Transformer Isolation: 1500 V RMS.
Surge Protection: Silicon Avalanche Diodes, 600 watts RMS power dissipation @ 1 ms, with response time
of less than 1 ps.
Power Supply: Wallmount power supply: 120 VAC
INTRODUCTION:
Description:
The Aysnc/Sync Short Haul Modem operates 2-wire (half-duplex) or 4-wire (full- or half-duplex), in synchronous or asynchonous modes,
over unconditioned telephone lines. The Modem has an extended range of 20 miles (32 km). It operates at 12 switch-selectable data rates to
57.6 Kbps. The modem always operates in sychronous mode between the local and remote modems; when connected to an asynchronous
RS-232 devices, the modem converts the asynchronous data to synchronous data.
The modem has several feautres to enhance overall performance: automatic equalization, automatic gain contrl, anti-streaming timer,
transformer isolation to guard against data loss because of ground-potential differences, and Silicon Avalanche Diode surge protection to
guard against data-line transients.
The modem features V.52-compliant bit-error-rate pattern tests and two V.54 test modes: local analog loopback and remote digital
loopback. The operator at the local end may test both local and remote modems, plus the line, in the digital loopback mode. Both RDL and
LAL modes can be controlled by a manual switch or vis the V.24/RS-232 interface.
TD
RD
RTS
CD
ERROR
TEST
TOGGLE
SWITCHES
BOTTOM OF UNIT
ME475A
V.54 Test Modes
1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8
S1 S2 S3
ON ON ON

Black Box ME475A Specifications

General

Brand	Black Box
Model	ME475A
Category	Modem
Language	English

Summary

Specifications

Transmission and Interface Details

Covers format, interface types (RS-232, RJ-45, terminal block), and transmission line specs.

Operational Parameters

Includes data rates, clocking, controls, applications, and indicators.

Diagnostics and Protection

Details V.52/V.54 diagnostics, transformer isolation, and surge protection.

Introduction

Modem Overview

General description of the async/sync short haul modem's capabilities and features.

Configuration Settings

Switch Groups S1 and S2

Explains settings for data rate, clock source, async/sync mode, carrier control, word length, and RTS/CTS delay.

Extended Signaling Rate and Test Modes

Covers switch settings for signaling rate variability and V.52/V.54 test modes.

2-Wire/4-Wire Mode Selection

Details switch S2-7 for choosing between 2-wire and 4-wire operation.

Input Impedance and Mode Selection

Details switches S3-1, S3-2 for impedance and S3-4 for point-to-point/multipoint modes.

Loopback and Anti-Stream Control

Covers switches S3-5, S3-6 for loopback initiation and S3-7, S3-8 for anti-stream control.

Installation

Two-Wire Installation

Guides for half-duplex operation over single twisted-pair, RJ-45 and terminal block connections.

Four-Wire Installation

Guides for full/half-duplex over two twisted-pairs, RJ-45 and terminal block connections.

Four-Wire Multipoint Installation

Covers multipoint setup with master/slave configuration and star topology.

Operation

LED Status Monitors

Explains the function of front panel LEDs for TD, RD, RTS, CD, Test, and Error.

Test Indicator and Error Functions

Details the green Test LED and the Error LED's multiple functions including line quality.

Cable Quality Testing Procedure

Provides a procedure using LEDs and switch settings to test 4-wire cable quality.

Anti-Streaming Error Indicator

Explains how the Error LED indicates RTS streaming when anti-stream is enabled.