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serial network tail circuit buffer




Features / Benefits

  • Interface - RS-422/449
  • Optional: RS-530, V.35, RS-232 or X.21
  • Selectable delays of 5mS up to 1250mS in 5mS increments
  • Data Rates - Synchronous to 10Mbps
  • Status LED's for each port allows ease of connection and trouble shooting
  • Timing - accepts external timing from attached DCE
  • 110/220VAC switch selectable
  • Sturdy Metal Enclosure for standalone or rackmount installations


The Selectable Transmit Buffer(RDS-STB) allows DCE to DTE connections at data rates up to 10Mbps. The user selectable buffer delays are for both data and a control signal in each direction and range from 5 milliseconds(mS) to approximately 1250 mS, in 5 mS increments. The STB allows users to transmit data to

critical DCE/DTE equipment such as satellite receivers, digital service unit(DSU) or other network access device for reliable network operation while fine tuning network delay times.
An example utilizing the STB is to allow the user to even the network delays between a terrestrial and satellite network for financial transactions.

The STB has individual data interfaces that allow V.35, RS-530, RS-422/449, RS-232 and X.21 connections for both DCE and DTE interfaces. The data interfaces may also be mix and matched such as V.35-to-RS-530 connections.

The STB has status LED's for each attached device which allows the user to visually confirm the presence of control signals.

Installation is fast and simple by setting the switches for delay time, clocking and Clear To Send(CTS) control.

The RDS-STB uses state of the art digital CMOS technology to provide a feature filled product at an affordable price. The units design offers a field programable gate array(FPGA) for fast customer specified changes.

The unit is housed in a sturdy metal enclosure and operates on 110/220VAC.

The unit has a three year warranty and a 24 hour turnaround on warranty repairs.

tail circuit buffer diagram


Application Interconnection of a DCE and DTE device located within proximity of each other while simulating network delays times
Delay Times 5 milliseconds(mS) to approximately 1250 mS, in 5 mS increments
Note: Baud Rate effects total delay times
Capacity One(1) DCE device
One(1) DTE device
Data Rates Up to 10Mbps
Data Channel Interfaces Available in V.35, RS-530, RS-422/449, RS-232 or X.21
Power Source 100-120 to 200-220VAC @10%, 50/60Hz, 0.16/0.08A, 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%
Altitude............................0 to 10,000 feet
Dimensions Height ....... 1.75 inches (4.44 cm)
Width ........ 7.90 inches (20.07 cm)
Length ....... 9.00 inches (22.86 cm)
Weight 2 pounds (0.914Kg)
Warranty Three Years, Return to Factory
Ordering Information: Model: RDS-STB
Description: Selectable Transmit Buffer
Interfaces Available:
V.35, PT# 129010
RS-530, PT# 129011
RS-422/449, PT# 129012
X.21, PT# 129013
RS-232, PT# 129014
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
 Surge Protection  Main power supply
Optional Accessories 1) Spare Data Center Fuses
A) 160ma Fuse, Qty (2) Part # 714000
B) 80ma Fuse, Qty (2) Part # 714001