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Wan Raptor Network Emulator
RDS-Plus, Data Link Simulator
PDS-1/10G Portable Delay Simulator

Network Emulator Testing
10 / 100 / 1000, 10G, 25G & 40G

RDS-PLUS, Data Link Simulator

RDS-Plus, Data Link Simulator
Latency Emulator & BERT
Testing for Serial Data and Telcon Interfaces


Network Impairment testing
Latency, Loss, Jitter & Re-Ordering

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Products for Global Networks
Manufacturing Network latency Emulators, IP Traffic
Generators and Data Communication Equipment since 1994.

About East Coast Datacom, Inc

East Coast Datacom, Inc. is a customer oriented, high technology enterprise which was formed in 1994 to design, manufacture and support Wide Area Network Equipment. We manufacture the broadest line of Network Emulators in the network test equipment market supporting over 18 different interfaces for Serial, Telco and Ethernet.

For Ethernet, the WanRaptor™ Network Emulator allows users to test and stage critical network equipment adding network latency, loss, Jitter and re-ordering impairments. For Serial data and Telco the RDS-PLUS delay simulator is a modular, network link error and delay emulator that provides a realistic simulation of physical network behavior with respect to time delays and bit errors.

We also manufacture an extensive line of legacy network equipment critical to the military, government and Fortune 500 companies. These include data broadcast splitters, digital sharing devices, interface converters and many other network adapters. Our highly respected Sync2IP Converter is a unique solution for Sync data to IP conversion as we support any sync data protocol.

We hope you enjoy our collection of products we present on our web site. Keep in mind we can modify or design a new solution for your unique application.

Our Featured Products

Select a category you are interested in and explore what we have to offer you. We manufacture a full line of data communication equipment and network latency simulators.

Network Emulators

Application Performance Testing
Network Latency Simulators

Serial Network Adapters

Converts Sync Serial Data to IP Transport
Serial Network Adapters

Data Broadcast Units

Simplex Data Broadcast for RS-232 or V.11
Data Broadcast Units

Features / Benefits

  • Interface - X.21, ITU V.11, (5) DB-15 Female Connectors
  • Data Rates - Synchronous up to 1.024Mbps
  • Anti-Streaming - Automatic or Manual for unattended Circuit Restoral
  • Individual Subchannel Enable/ Disable Switches
  • Integral Elastic Tail Circuit Buffer - FIFO capable of 512 bits per channel
  • Up to Four DTE or DCE's per Link
  • Transparent to Data
  • Supports Fall Back Clocking
  • Sturdy Metal Enclosure
  • 110/220VAC Switch Selectable


The X.21 Digital Sharing Device DMM-X21 provides the network manager with a cost effective means of expanding existing, leased line polled networks without adding computer ports or communications links. With the DMM-X21, up to 4 DTE or DCE devices can share the same port and communications link using the contention and control protocols normally resident in the host hardware and software.

Once installed, system and network efficiency are increased through higher host processor utilization coupled with the significant decrease in idle time between host / terminal traffic sessions.

Ideal for synchronous network environments, the DMM-X21 is protocol transparent at data rates up to 1.024Mbps. Data arriving at the Master Port is continually broadcast to all Subchannels. The attached terminal device that raises the Control (C) or Indicate (I) signal is automatically given control of the DMM-X21 until data transmission is complete. Clocking is accomplished from the attached Digital Modem.

The DMM-X21 incorporates optional Anti-Streaming circuitry. If enabled, Anti-Streaming will automatically remove a defective terminal from service if the Control (C) or Indicate (I) signal is present longer than the user predefined selection period.

Elastic Tail Circuit Buffers compensate for systems having different clock sources. Large 512 bit buffers enable the DMM-X21 as an ideal choice for VSAT or land line applications.

The DMM-X21 is equipped with an internal 110/220VAC switch selectable linear power supply and has a three year warranty.



Application Multiple X.21 Synchronous DCE or DTE devices contending in a polled environment, to share one Digital DCE or DTE interface
Capacity One to Four CCITT X.21 devices
Interface CCITT X.21, V.11 using DB-15 female connectors
Data Format Data transparent at all data rates
Data Rates Up to 1.024Mbps
Timing From Composite (Master) Port,Sub-channel Port 1
or Port 4
Buffers Up to 512 bits per channel
 Anti-Streaming Automatic.....Selectable time out intervals

Disable.........Selectable via dip switch

 Front Panel Indicators....Power, Send/Receive Data, Channel Active, Channel Stream

Switches.....Enable/Disable of each Subchannel

Power Source 100-120 to 200-220VAC @10%, 50/60Hz, 0.32/0.16A, external 110/220 volt select switch, IEC Power Inlet, (2) 5mm Fuses
Environmental Operating Temperature . .32º to 122º F (0º to 50º C)

Relative Humidity.. . . . . . .5 to 95% Non-Condensing

Altitude. . . . . . . . . . . . . ... .0 to 10,000 feet

Dimensions Height ....... 1.75 inches (4.44 cm)

Width ........ 17.00 inches (43.18 cm)

Length ....... 9.00 inches (22.86 cm)

Weight 4.5 pounds (2.1Kg)
Warranty Three Years, Return To Factory
Regulatory Approvals Tested According to UL 60950-1:2003, CAN/CSA-C22.2 No. 60950-1:2003CE Safety EN60950 and CE EMC EN300-386-2
Ordering Information Model: DMM-X21
Description: 4 Port Digital Sharing Device
Included with each unit: 1) Operations Manual

2) U.S.A. Grounded Power Cord, Part # 713015

3) Optional Power Cords

....A) United Kingdom, Part # 713016

....B) Continental Europe, Part # 713017

....C) Other: Specify Country on Purchase Order


1) Spare Data Center Fuses

....A) 160ma Fuse, Qty (2) Part # 714000

....B) 80ma Fuse, Qty (2) Part # 714001