Black Box Fiber Drivers

Ensure Reliable Transmission Over Fiber


What's special about these fiber optic drivers?

  • High-performance drivers enable you to send RS-232 data across interference-free optical links
  • Sends RS-232 data, at up to 76.8 kbps, from serial devices to a server over multimode fiber cable
  • Switch-selectable DTE/DCE option, set to perform like a DTE so it can communicate with another DCE device, no special cables are needed
  • Click for More Features

The Black Box high performance fiber drivers are powered to ensure continuous, reliable transmission over fiber. These fiber drivers enable you to send RS-232 data across interference-free optical links, transmit data at up to 76.8 kbps, and reach distances of 2.5 miles at any speed.

Part #DescriptionDimensionsWeightPrice
BB-MD940A-FFiber Driver ST/25 Female1" H x 2.7" W x 4.2" D1.4 lbs
Manufacturer Direct
BB-MD940A-MFiber Driver ST/25 Male1" H x 2.7" W x 4.2" D1.4 lbs
Manufacturer Direct
  • Reach distances of 2.5 miles (4 km) at any speed
  • Autosensing 110–220-VAC power supply ensures reliability and continuous transmission
  • Coupled power variations are compensated by a range select feature
  • Supports RS-232 async, bidirectional transmission
  • Use with multimode fiber cable
  • 1 Year Double Diamond Protection
Data Format Asynchronous, bidirectional
Data Rate Transparent up to 76.8 kbps
Distance Dependant 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
CE Approval Yes
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
Operating Temperature 32°F to 114°F (0°C to 45°C)
Size 1" H x 2.7" W x 4.2" D (2.5 x 6.9 x 10.7 cm)
Weight 1.4 lbs (0.6 kg)


The Double Diamond Warranty is our no-questions-asked warranty that protects your BLACK BOX® brand products from accidental damage, including drops, water, and power surges. Most products come with a one- or two-year warranty. Some products, such as copper cables, manual switches, cabinets, and racks, are guaranteed for life! During the warranty period, Black Box will repair or replace your damaged equipment within one week of receipt at NO CHARGE!





Did you know that we can give you a quote for most of our products, including shipping?

You can also call us toll free 1-833-3CABLEORG (1-833-322-2536)>

Questions & Answers

Do you have any questions about this product?
Let our experts and customers resolve all your doubts