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serial data async to sync rate adapter

Features / Benefits

  • Interface - Async is RS-232 Sync is RS-422, RS-530, X.21 or V.35
  • Data Rates - Async is 1.2k, 2.4k, 4.8k, 9.6k, 19.2k, 38.4k, 57.6kbps or 115.2kbps
    Sync is 16k, 64kbps or 128kbps
  • Allows low speed async terminals to access high
    speed 16k, 64k or 128k sync circuits
  • Compact and easy to install
  • Line powered from data interfaces
  • Sturdy Metal Enclosure


The RA-64/128K Rate Adapter allows low speed async RS-232 DTE equipment
to transmit over a high speed 16k, 64k or 128k sync communications link.

The RA-64/128k devices are used in pairs, one at each end of the communications
link or in multiples as when used in a multi-point or broadcast communications
link. The RA-64/128k will support bi-directional or simplex data transmissions.


The RA-64/128k supports async character length of 8, 9, 10 and 11 bits,
including the start and stop bit. The asynchronous interface is RS-232 and
supports data rates of 1.2k, 2.4k, 4.8k, 9.6k, 19.2k, 38.4k, 57.6k or 115.2k. The synchronous
data interface rate must be set at 16k, 64k or 128k and will support data
interfaces of X.21, RS-422, RS-530 or optional V.35.

The RA-64/128k will support V.35 by ordering the unit under part number
147000. The V.35 data interface will support both the old V.35 (+/-0 .5 volts) or
newer V.35 (ITU recommendation V.11) ground to +3.8 volts. A DB-25 male to
V.35 male 6 foot adapter cable is required for V.35 termination. The cable
should be ordered under part number 712005.

The RA-64/128k derives its power through the async and sync data interfaces.
The device utilizes leading edge technology for reliable, low power
operation. The user should insure that the RA-64/128k has a minimum of
three synchronous control signals available for proper operation.

The RA-64/128k is housed in a sturdy metal enclosure, has a three year
warranty and a 24 hour turnaround on warranty repairs.

64k rate adapter diagram 128k Rate Adapter Diagram


Application Interconnection of a low speed asynchronous terminal or DTE device operating at 1.2k, 2.4k, 4.8k, 9.6k, 19.2k, 38.4k, 57.6k or 115.2k to a synchronous 16k, 64k or 128k modem or DCE device
Capacity One terminal(DTE) and one modem(DCE)
Data Channel Interfaces Async: RS-232
Sync: RS-422, X.21, RS-530 and V.35
Switches Internal Switches for Baud Rate, Character Length and Crystal setting
Data Rates Async: 1.2k, 2.4k, 4.8k, 9.6k, 19.2k, 38.4k, 57.6k or 115.2k
Sync: 16k, 64k or 128k
Switches Provided for async data set-up, stop bit reduction and signal to frame ground
Enclosure Metal: Aluminum
Power Source Line powered from data interfaces
Requires minimum of 3 control signals
Environmental Operating Temperature....32º to 122º F (0º to 50º C)
Relative Humidity.............5 to 95%
Altitude............................0 to 10,000 feet
Dimensions Height ....... 0.50 inches (1.27 cm)
Width ........ 1.75 inches (4.44 cm)
Length ....... 3.90 inches (9.91 cm)
Weight 1/2 pound (0.225 Kg)
Warranty Three Years, Return To Factory
Ordering Information Model: RA-64/128k_V11
Part Number: 146000
Description: RS-232 Async(19.2k, 38.4k, 57.6k &115.2k to V.11 sync 64k or 128k Rate Adapter
* V.11 supports RS-422, X.21 and RS-530

Options for RA-64/128k_V11:
Part Number:712014
Description:6 ft.,DB-25 to X.21 adapter cable
Part Number:712015
Description:6 ft.,DB-25 to RS-422 adapter cable

Model: RA-64/128k_V35
Part Number: 147000
Description: RS-232 Async(19.2k, 38.4k, 57.6k & 115.2k to V.35 sync 64k or 128k Rate Adapter

Options for RA-64/128k_V35:
Part Number:712005
Description:6 ft.,DB-25 to V.35 adapter cable
Included with each unit: 1) Operations Manual