1
Protects data against
crosstalk and outside
noise interference.
Point-to-point or
multipoint operation,
full- or half-duplex.
Rates up to 9600 bps.
Uses Frequency Shift
Keying modulation.
Provides highly
reliable, continuous
data transmission.
Optional modules
available for 2-wire
RS-485 and 4-wire
RS-422.
T
he Short-Haul Modem-FSK
is a private-line modem that
supports 9600-bps half- and full-
duplex RS-232 operation over a
single dedicated wire pair and
across sliding contacts. The
modem uses pure Frequency Shift
Keying (FSK) modulation at high
carrier frequencies (100 kHz,
106.5 kHz to 150 kHz, 156.5 kHz).
These high frequencies make the
modem particularly immune to
crosstalk and outside noise
interference, so you get highly
reliable, continuous data
transmission over distances of
several miles in harsh industrial
environments.
Extend communications over a single pair—
even in the noisiest environments!
Key Features
SHORT-HAUL MODEM-FSK (SHM-FSK)
The modem operates in point-
to-point or multipoint applications.
For multipoint applications, the
modem can be operated with
one master unit and up to eight
remote units.
The master unit (ME840A-M)
transmits at 106.5/100 kHz
(Space/Mark) and receives at
156.5/150 kHz.
The remote slave unit
(ME840A-S) transmits at 156.5/
150 kHz and receives at 106.5/
100 kHz.
Since RS-485 interfaces are
common in industrial applications,
we also offer a 2-wire RS-485
module (MD3317) and a 4-wire
RS-422 module (MD3318). Simply
plug the module into the modem’s
RS-232 connector and you’ve got
your extra connection.
The modem has several
diagnostic LEDs: Carrier Detect,
Receive Data, Transmit Data,
Loopback, and Power.
The modem interface is
DTE/DCE jumper selectable, so
it’s easy to configure to suit your
application. The default configur-
ation for the Modem is DCE. To
change this configuration, just
move the jumpers on blocks P1
and P2 (located directly behind
the DB25 RS-232 connector on the
rear panel).
The modem also includes
jumpers for cofiguring carrier
detect, chassis ground, receiver
gain, and transmit power.
Black Box Corporation
• 1000 Park Drive • Lawrence, PA 15055-1018 • Tech Support: 724-746-5500 •
www.blackbox.com
•
e-mail: [email protected]
© 2003. All rights reserved.
Black Box Corporation.
11/21/2003#18966
