Black Box ME605A-FST User manual

APRIL 1998
ME605A-FST
ME605A-MST
Async Fiber Optic Mini Modem
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 [phone]
Mail order: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018
Web site: www.blackbox.com • E-mail: [email protected]
DATA
TX RX

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TRADEMARKS
TRADEMARKS
The trademarks mentioned in this manual are the sole property
of their owners.

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ASYNC FIBER OPTIC MINI MODEM
CONTENTS
1. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.3 Application. . . . . . . . . . . . . . . . . . . . . . . . . . 8
3. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

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CHAPTER 1: Specifications
1. Specifications
Data Rate — Up to 19.2 Kbps
Pulse Width Distortion — Less than 25%
Transmission Line — Duplex optical cable
Transmission Mode — Asynchronous, full-
or half-duplex
Transmission Controls — Carrier constantly on
or controlled by RTS
Optical Output Levels — -28 dBm into 100/140 fiber;
-32 dBm into 62.5/125 fiber;
-36 dBm into 50/125 fiber
Receiver Sensitivity — -45 dBm
Operating Wavelength — 850 nm
Operating Range — Maximum range is 2 miles (3 km)
of continuous fiber with the following fibers: 100/140
fiber with attenuation of 4 dB/km; 62.5/125 fiber with
attenuation of 3.5 dB/km; 50/125 fiber with
attenuation of 3 dB/km

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ASYNC FIBER OPTIC MINI MODEM
Indicators — (1) Power LED
Terminal Interface — (1) ITU V.24/EIA RS-232C
integral DB25 male or female connector
Fiberoptic Interface — (2) ST connectors
Temperature — 32 to 122°F (0 to 50°C)
Humidity — Up to 90%, noncondensing
Power — None required; uses ultra-low power
from the data and control signals
Size — 0.7”H x 2.1”W x 3.1”D (1.8 x 5.3 x 7.8 cm)
Weight — 1.3 oz. (36 g)

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CHAPTER 2: Description
2. Description
2.1 General
The Async Fiber Optic Mini Modem is used for local
data distribution, connecting full- or half-duplex async
computers and terminals. A pair of modems ensures
integrity of data transmission over fiberoptic cable at
distances up to 2 miles (about 3 km).
The Modem features a switch-selectable DCE/DTE
option. This allows operation as DTE, for connection to
another DCE such as a multiplexor port, eliminating the
need for a cross cable. The carrier can be strapped for
either continuous operation, or for switched operation,
controlled by the RTS signal, for transfer of a control
signal end-to-end.
Innovative circuitry allows the Modem to operate
without connection to the mains power supply, by
using ultra-low power from the data and control signals.
The Modem operates even if only transmit data is
connected—no control signals or any other source
of power are required.

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ASYNC FIBER OPTIC MINI MODEM
The Modem comes in a durable plastic case.
The Modem incorporates all the advantages
of a fiberoptic system, providing:
• Lower attenuation than with copper wire.
NOTE
Attenuation is not related to frequency.
• EMI/RFI immunity, saving the cost of expensive
and heavy shielding, and complex error checking
routines.
• Almost absolute security and reduction in the
cost of data encryption; eavesdropping is virtually
impossible since negligible power is radiated from
the fiber.
• Safety and electrical isolation: no spark hazard
and no ground-loop noise problems.

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CHAPTER 2: Description
2.2 Features
• Asynchronous transmission up to 19.2 Kbps.
• Transmission range up to 2 miles
(about 3 km), regardless of data rate.
• Full- or half-duplex operation.
• Transfers one control signal end-to-end.
• DCE-DTE switch.
• No external power required.
• Plugs directly into V.24/RS-232C terminal
connector.
• Compact, lightweight, and easy to install.

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ASYNC FIBER OPTIC MINI MODEM
2.3 Application
A pair of Async Fiber Optic Mini Modems ensures
secure data transmission over fiberoptic cable at
distances up to 2 miles (about 3 km).
Figure 2-1. Typical application of the modem.
ME605A ME605A
Async
Computer
Async
Terminal
Fiberoptic Cable
2 miles (3 km)

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CHAPTER 3: Installation
3. Installation
Installation of the Modem is simple. Just follow these
instructions:
1. To access the switches, insert a slim screwdriver
under the nameplate and ease the nameplate off.
2. Strap the modem according to the strapping
diagram (Figure 3-1) and the strap selection
table (Table 3-1). Explanations of the switches
are also given on the printed circuit board.
Figure 3-1. Strapping diagram.
DATA
TX RX
DTE
DCE
SW1
SW2
CARR
DLY
CL ON
15ms 2ms