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Fiber Driver, ST to DB25 Female  

Send RS-232 data across interference-free optical links with these high-performance drivers.


Extended Double Diamond™ Warranty Available (3 Additional Year)

Product Highlights

  • Powered to ensure continuous, reliable transmission over fiber.
  • Send RS-232 data from serial devices to a server over fiber cable.
  • Transmit data at up to 76.8 kbps.
  • Reach distances of 2.5 miles (4 km) at any speed.

  • Further Details

  • Autosensing 110–220-VAC power supply ensures reliability and continuous transmission.
  • A range select feature compensates for coupled power variations.
  • Switch-selectable DTE/DCE option. Set to perform like a DTE so it can communicate with another DCE device. No special cables are needed.
  • Support RS-232 async, bidirectional transmission.
  • Use with multimode fiber cable.

  • Approvals CE
    Data Format Asynchronous, bidirectional
    Data Rate Transparent up to 76.8 kbps
    Distance Dependent on type of multimode cable, power budget, and loss/km; preset ranges
    Fiber Cable 850-nm multimode
    Flow Control X-ON/X-OFF
    Operation Full-duplex
    Interface RS-232 (DCE or DTE switch selectable)
    Connectors (2) ST®; (1) DB25 M or F
    Power 5 VDC @ 600 mA;
    External: 110-220 VAC, 50-60 Hz, autosensing
    Dimensions 1"H x 2.7"W x 4.2"D (2.5 x 6.9 x 10.7 cm)
    Weight 1.4 lb. (0.6 kg)

    This product works with:
  • Multimode Distribution-Style, Fiber Optic Bulk Cable, Plenum, Custom Lengths, 12-Fiber (EXP3012A or EXP35012A)
  • Premium Ceramic, Multimode, 62.5-Micron Fiber Optic Patch Cables, ST–ST (EFN110 or EFP110)
  • Standard RS-232 Low-Noise Cable, 25-Conductor (ECM25T-0010).
  • Questions? Contact our FREE Tech Support.

    NOTE: Technical specification weight is the unit weight. It is not the packaged shipping weight. For shipping weight, please contact Black Box customer service at 1-800-316-7107.

    Double Diamond Warranty
    Extended Double Diamond™ Warranty Available (3 Additional Year)

    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 Fiber Driver, ST to DB25 Female comes with a standard 1 Year warranty 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.

    Product SKU Price Quantity
    ST to DB25 Male Fiber Driver MD940A-M $248.45
    You can find this product in the following subcategory(s)

    Add to Cart

    Price: $248.45

    On Back Order




    Shipping Info

    Weight: 0.875 lbs.
    HxWxD: 3.25 x 4.25 x 9.6 in.

    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.

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    Black Box 1-800-316-7107 Black Box Network Services