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Async/Sync Short-Haul Modem

Send async or sync RS-232 data up to 57.6 kbps or 7.6 miles.


Please call 877-877-2269 for a replacement product or part.
Extended Double Diamond™ Warranty Available (3 Additional Year)

Product Features

  • Distances from 5.3 to 11.4 miles (8.5 to 18.3 km) over 24 AWG (speed dependent).
  • Async or sync, point-to-point or multipoint operation.
  • Transformer isolation and surge protection.


  • Internal, external, or receive recover clocking in sync mode.
  • V.54 loopback and V.52 BERT pattern generator.

  • The BLACK BOX® Async/Sync Short-Haul Modem sends your data 5.3 miles (8.5 km) at up to 57.6 kbps over 24 AWG wire or as far as 11.4 miles (18.3 km) at 1200 bps. Need more than just high performance? This short-haul modem comes with lots of extras to simplify your data transmission. Transformer isolation and surge protection help to guard your valuable data, and front-panel controls make it easy to configure diagnostics.

    Of course, the Async/Sync Short-Haul Modem has all the standard features you’re used to: async or sync operation, the option of running point-to-point or multipoint applications, and half-duplex operation over two wires or your choice of half- or full-duplex over four wires.

    Tech Specs

    Approvals CE
    Clocking Internal, External, ReceiveDistance (Maximum) 11.4 mi. (18.3 km)
    Connectors (1) DB25 F, (1) RJ-45, (1) terminal block
    Dimensions 1.5“H x 4.2“W x 5“D (3.8 x 10.7 x 12.7 cm)
    Interface RS-232 (DCE)
    Operation 2-wire half-duplex or 4-wire half- or full-duplex
    Power 115-VAC, 60-Hz external transformer
    Speed 57.6 kbps maximum

    NOTE: Compatible with Multi-Function Line Driver Cards (ME758C).

    This product works with:
    • GigaBase® 350 CAT5e, 350-MHz Bulk Cables, 4-Pair (EYN851A)
    • RS-232 Cable, 25-Conductor (ECM25C)
    Questions? Contact Tech Support.

    * Technical specification weight is the unit weight. It is not the packaged shipping weight. For shipping weight, please contact Black Box customer service at 877-877-2269.


    Double Diamond Warranty

    Extended 1 Year Warranty Available

    Protect your purchase with an additional 1 Year Double Diamond™ warranty!
    Cost: $34.30

    Extended 3 Year Warranty Available

    Protect your purchase with an additional 3 Year Double Diamond™ warranty!
    Cost: $68.59


    Double Diamond™ Warranty (Standard)

    Take the risk out of equipment purchases with the Double Diamond™ Warranty from Black Box Network Services.

    The Double Diamond Warranty is our warranty that protects your Black Box® brand products* from accidental damage, including drops, water, and power surges.

    The Async/Sync Short-Haul Modem comes with a standard 1 Year Double Diamond™ Warranty (Standard) already included.

    During the warranty period, Black Box Network Services will repair or replace your damaged equipment within one week of receipt at NO CHARGE!*

    Plus, get an Extended Double Diamond Warranty.

    You can also extend your warranty or protect a previously purchased Black Box® brand product** for an additional year—for only 10% of the purchase price! Or, extend your coverage for a full three years for only 20% of the purchase price!

    Ordering an extended warranty is easy: When viewing a product in your shopping cart, just select the one or three years of additional coverage in the dropdown menu under “Warranty Options.” For details, contact Customer Service at 724-746-5500.

    * Warranty subject to certain exclusions and limitations ** Certain products may not be eligible.

    What’s more, we also have a 45-day return policy. Simply call Customer Service for a Return Authorization (RA) number, return your product in new condition and in the original package, and receive a full refund.