Black Box ME1240A-F User manual

JULY 2003
ME1240A-F ME1243A-F
CUSTOMER
SUPPORT
INFORMATION
Order toll-free in the U.S.: Call 877-877-BBOX (outside U.S. call 724-746-5500)
FREE technical support 24 hours a day, 7 days a week: Call 724-746-5500 or fax [phone]
Mailing address: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018
Web site: www.blackbox.com • E-mail: [email protected]
Miniature Modem Eliminators

Features 1
ME1240A-F, ME1243A-M
1. Features
Miniature modem eliminators:
• Synchronous operation
• Selectable data rates up to 38.4 kbps (ME1240A-F) or 64 kbps (ME1243A-F)
• V.24 (ME1240A-F) or V.35 (ME1243A-F)
• Range of 30m/99 ft (ME1240A-F) or 75m/247 ft (ME1243A-F) on each side
• Selectable RTS to CTS delay
• Carrier controlled or constantly ON
• Easy to install and configure
• Miniature, lightweight.
Versions
The following versions of the modem eliminators are available:
• ME1240A-F – modem eliminator with RS-232/V.24 interface, operating with
internal or external clock at data rates of up to 38.4 kbps
• ME1243A-F – modem eliminator with V.35 interface, operating with internal
clock at 64 kbps.
Application
Host Terminal
ME1240A-F,
ME1243A-F
Figure 1. Typical Application

ME1240A-F, ME1243A-M
2 Technical Specifications
2. Description
ME1240A-F and ME1243A-F are miniature modem eliminators, which replace two
synchronous modems by permitting direct port-to-port connection, as shown in
Figure 1.
The modem eliminators operate at to 38.4 kbps (ME1240A-F) or 64 kbps
(ME1243A-F), connecting two synchronous DTEs at ranges of up 30m/99 ft
(ME1240A-F) or 75m/247 ft (ME1243A-F) on each side.
The delay between RTS and CTS can be independently set on either port to 0, 6.6
or 53 msec for ME1240A-F or 0, 7, or 64 msec for ME1243A-F.
The DCD signal can either be set to constantly ON, or used as a port-to-port
handshaking signal, where RTS on one port is converted to DCD on the other port.
Physical connection between ME1240A-F and its associated terminal and
computer is via D-type 25-pin female connectors.
Physical connection between ME1243A-F and its associated terminal and
computer is via two 34-pin V.35 female connectors on 85 cm (2.8 ft) cable.
3. Technical Specifications
Transmission Format Synchronous
Mode Emulates half or full duplex lines
Data Rate ME1240A-F: 2.4, 4.8, 9.6, 19.2, 38.4 kbps
ME1243A-F: 64 kbps
Range ME1240A-F: 30m (99 ft) on each side
ME1243A-F: 75m (247 ft) on each side
RTS/CTS Delay ME1240A-F: 0, 6.6 or 53 msec
ME1243A-F: 0, 7, or 64 msec
DCD Continuously ON or controlled by RTS from
the DTE on the other side
Interface ME1240A-F: V.24
ME1243A-F: V.35
Connectors ME1240A-F: D-type, 25-pin, female
ME1243A-F: 34-pin, female
Power No external power supply is required
Physical ME1240A-F
Height 30 mm / 1.2 in
Width 50 mm / 2.0 in
Depth 135 mm / 5.3 in
Weight 100g / 3.5 oz

ME1240A-F, ME1243A-M
Technical Specifications 3
ME1240A-F
Height 30 mm / 1.2 in
Width 50 mm / 2.0 in
Depth 130 mm / 5.1 in
Weight 300g / 10.5 oz
Environment Temperature 0–50°C (32–122°F)
Humidity Up to 95%, non-condensing

ME1240A-F, ME1243A-M
4 Installation
4. Installation
This is a delicate instrument. Be careful when setting jumpers or performing any
actions within the product so that you do not break or shake any components.
Installation of the modem eliminators is simple and straightforward, just follow
these steps:
1. Separate the two parts of the plastic cover by firmly pressing the marked places
on the sides. If this is difficult, insert a small screwdriver into the slot, where
there is a small opening. Lift the handle, gently levering the tip of the
screwdriver down. The cover will separate without pressure.
Do not insert the screwdriver straight into the middle of the slot, as this may break
off the prongs which snap the cover together.
2. Configure the unit according to the desired mode, referring to Figure 2,
Figure 3 and Table 1.
DLY1
JP1 JP5
DLY2
J1 J2
JP7
GND
0 ms 0 ms
6.6 ms 6.6 ms
53 ms 53 ms
JP3
JP2
XMT
TIMING
BAUD RATE JP6JP4
ONON
CTRCTR
CARR2CARR1
EXT
INT
9.6
4.8
2.4
19.2
38.4
Figure 2. ME1240A-F Internal Jumper Locations
DLY-1 DLY-2
0 msec 0 msec
7 msec 7 msec
64 msec 64 msec
CD 1
CD 2
ON
ON
CTR
CTR
Figure 3. ME1243A-F Internal Jumper Locations
Table 1. Internal Jumper Settings
Jumper Function Possible Settings Default Setting
XMT TIMING
(ME1240A-F only)
Selects transmit timing for
ME1240A-F unit
INT – Internal
EXT – External from DTE EXT
BAUD RATE
(ME1240A-F only)
Selects data rate for
ME1240A-F unit
38.4 – 38.4 kbps
19.2 – 19.2 kbps
9.6 – 9.6 kbps
4.8 – 4.8 kbps
2.4 – 2.4 kbps
9.6
Caution
Caution

ME1240A-F, ME1243A-M
Installation 5
Table 1. Internal Jumper Settings (Cont.)
Jumper Function Possible Settings Default Setting
CARR1 (ME1240A-F)
CD1 (ME1243A-F)
Selects the carrier to be
constantly ON or controlled
by RTS (port 1)
ON – Constantly ON
CTR – Controlled by RTS
ON
CARR2 (ME1240A-F)
CD2 (ME1243A-F)
Selects the carrier to be
constantly ON or controlled
by RTS (port 2)
ON – Constantly ON
CTR – Controlled by RTS
ON
DLY1 Selects delay between
receipt of RTS and CTS
(port 1)
ME1240A-F:
0ms
6.6 ms
53 ms
ME1243A-F:
0ms
7ms
64 ms
6.6
7
DLY2 Selects delay between
receipt of RTS and CTS
(port 2)
ME1240A-F:
0ms
6.6 ms
53 ms
ME1243A-F:
0ms
7ms
64 ms
6.6
7
GND (ME1240A-F only) Controls connection of the
protective ground to the
signal ground
Jumper plug is on –
Protective ground (AA) is
connected to the signal
ground (AB)
Jumper plug is off –
Protective ground (AA) is
disconnected from the signal
ground (AB)
Jumper plug is on
3. Close the unit and connect to the computer and terminal.