Black Box Mini Driver 4W-S User manual

DECEMBER 1998
ME749A-F
ME749A-M
Mini Driver 4W-S
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]

1
TRADEMARKS
TRADEMARKS USED IN THIS MANUAL
Any trademarks mentioned in this manual are acknowledged to
be the property of the trademark owners.

2
MINI DRIVER 4W-S
1. Specifications
Transmission Mode — Synchronous, full-duplex
Transmission Line — Unconditioned/unloaded
4-wire (2 twisted pairs),
19 to 26 AWG
Transmission Level — -6 dBm
Transmission Range (miles) —
Speed (bps) Wire Gauge
19 24 26
19,200 3.5 2.5 2
9600 5.5 3.5 2.5
4800 7.5 5 3
2400 8.5 5.5 3.5
1200 11 7.5 5.5
NOTE: Multiply by 1.6 to derive ranges in km.
Baud Rates — 900, 1200, 1800, 2400, 3000,
4800, 7200, 9600, 14,400,
and 19,200 bps
Transmit Timing — Internal

3
CHAPTER 1: Specifications
Connectors — ME749-F: (1) DB25 female
and (1) 5-screw terminal
block;
ME749-M: (1) DB25 male
and (1) 5- screw terminal
block
Operating Temperature — 32 to 122°F (0 to 50°C)
Humidity Tolerance — Up to 95%, noncondensing
Power Supply — Supplied from the RS-232
interface
Size — 0.9"H x 2.1"W x 4.3"L
(2.2 x 5.3 x 11.0 cm)
Weight — 3.3 oz.(90 g)

4
MINI DRIVER 4W-S
2. Description
The Mini Driver 4W-S is a synchronous full-duplex,
4-wire short-haul modem with a range of up to eleven
miles. It is small in size, packaged inside a connector
cover. It can handle data rates of 900 to 19,200 bps.
The modems are to be used in pairs, one at each
end of the line.
The Mini Driver 4W-S requires no AC power supply,
batteries, or EIA test voltages. Very low power is derived
from the RS-232 data and control lines. It generates
positive and negative signals in compliance with the
RS-232 standard, even when Transmit Data is constantly
a MARK.
The Mini Driver 4W-S is isolated from the line by
balanced transformers. These transformers, together
with the electronic circuitry, protect the modem against
voltage transients.
The Mini Driver 4W-S’s low transmit level minimizes
crosstalk onto adjacent lines in the same cable. The use
of differential diphase modulation provides immunity
to background noise, eliminates line distortion, and
permits efficient transmission and reception of data.

5
MINI DRIVER 4W-S
Data is transmitted and received at a balanced imped-
ance which ensures excellent immunity to circuit noise.
The Mini Driver 4W-S is transformer-isolated from the
telephone line to protect against voltage spikes.
A typical installation is shown in Figure 1.
Figure 1. Typical Installation.
Unconditioned
4-Wire
(2 Twisted Pair)
Mini
Driver
4W-S
Mini
Driver
4W-S
Sync Terminal
Sync Host

6
MINI DRIVER 4W-S
3. Installation
1. Open the unit by pressing in the tabs on the side
of the cover with a small screwdriver.
2. Separate the top half of the case from the bottom
half.
3. Set the baud rate switch to the desired setting as
shown in Table 1. The factory default is 9600 bps.
See Figure 2 for the location of the switch. The
switch settings for the available baud rates are
printed on the underside of the circuit board.
Remove the circuit board from the case to access
this information.
Table 1. Baud Rate Settings
Baud Rate (bps) Switch Setting
900 9
1200 8
1800 7
2400 6
3600 5
4800 4
7200 3
9600 2 (Factory setting)
14,400 1
19,200 0

7
MINI DRIVER 4W-S
Figure 2. Baud Rate Setting Switch.
4. Connect the twisted-pair cable to the transmit
and receive screw-terminals. See Figure 3.
Figure 3. Installation Diagram.
5. Be sure that the screw locks for the RS-232
connector are in their mounting holes. Align
the top cover with the bottom cover and snap
them together.

8
MINI DRIVER 4W-S
6. Repeat steps 1 to 4 for the remote Mini Driver 4W-S.
Make sure the local transmit terminals are connected
to the remote receive terminals and that the local
receive terminals are connected to the remote
transmit terminals (see Figure 3).
7. Plug each Mini Driver 4W-S into the computing
device and tighten the screwlocks to prevent the
Mini Driver 4W-S from being disconnected from
the computer.
8. Each Mini Driver 4W-S is now ready for operation.

1000 Park Drive • Lawrence, PA 15055-1018 • 724-746-5500 • Fax [phone]
© Copyright 1998. Black Box Corporation. All rights reserved.