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Give Ron a Call at 513-874-4796 or 513-638-0228 for additional information.
VLF232 : Multimode Fiber to RS232 Full Duplex Serial Converter or Half Duplex Repeater


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Coming Soon!

"Let me spin a very large
RS485 network for you!"


Product Features

  • This versatile Fiber/RS232 unit will function as a full duplex master converter from Fiber <> RS232.

  • Configured as a half duplex fiber repeater, the RS232 port is a tap point to monitor data activity.

  • Transparent to all asynchronous data, with any combination of data, parity, and stop bits, at data rates up to 115.2 Kbps. No Jumpers or settings required.

  • The RS232 driver, provides communications at 100ft/9600bps, to 10ft/115.2Kbps.

  • Optimized for non-isolated office/indoor point to point or multi-drop systems.

  • Jumper J1, in position B-C, puts the unit into test mode when used with a loopback cable.

  • Edge mounted LEDs display power, data activity at the fiber interface, and the RS232 receive port.

  • Broad environmental range. 0C to +70C, reduced functionallity -40 to 85C. 10 to 90% RH(non-condensing)

  • Four(4) easy mount through hole standoffs, which accept #6 hardware, are provided on the circuit board.

  • User connections are a pair of fiber optic connectors, a 3 position location for Wago type or pin header, and a 2.1mm barrel connector or 2 pin terminal strip. Contact us for help in selecting connector types.

  • The fiber cable used with the installed connectors is a rugged 1mm low cost plastic type intended for limited distances of minimum 125 ft, typical 225 ft.

  • The onboard linear regulator accepts a source supply providing 8 to 15 VDC at 30 to 50 mA.

  • Accessories available are a 12VDC Switching Power Supply(Wall Wart), and an Enclosure.

  • Conformal Coating, cable, and connectors, are factory options. Contact us for options help.

  • WARNING: Do NOT connect this device to a telephone system under any circumstances. Damage could result to the circuit board and/or your telephone system.

  • R E Smith Inc makes a wide variety of isolated converters that address the electrical noise problems that contribute to unreliable communications, and product failure. If what you see here is not exactly what you need, don't hesitate in calling us at 513-874-4796.

  • We also have a new series of Converters and Repeaters that extend the RS485 communications distance far beyond conventional limits. Contact us for information on these leading edge problem solvers.

Product Description


Our unique auto transmit feature removes the burden of slowing down or spacing transmitted characters. After a character is transmitted, the RS485 transceiver is rapidly returned to the receive mode. No adjustments or tuning is required. This eliminates data collisions and lost characters due to slow turn-around. We pioneered this leading edge technology long before our competition.

About R E Smith, Inc:

R E Smith, Inc. engineers and manufactures a comprehensive line of isolated and non-isolated converters, repeaters, multiport repeater hubs, fiber optic based products, and I/O boards. All our products are designed, built, tested, and shipped from our facility in the Greater Cincinnati Ohio area. We ship small quantities of most products from stock the same day, and larger quantities in a few business days.

We listen to you. We are customer driven. Many of our products were developed and improved due to suggestions and feedback from our word-wide customer base. They are being used at the South Pole, at the bottom of the sea, at the edge of space, and everywhere in between. Typical uses are very large networks, monitor and control of elevators, machinery, lighting, security, fire and alarm, access, cameras, military ground support, and much more. We provide free support, no-argument warranty repairs, and recommendations for your application. Challenge us with your communications problem. We may already have the solution. If your system keeps failing, or is unreliable, we have isolated, doubly isolated, noise resistant, cost effective, and proven solutions for difficult environments.

Related Files:

PDF VLF232SSrevA Operation Notes

Physical Properties and Features:

Fiber: A pair of fiber optic connectors, one transmitter, one receiver
RS232: 3-position Wago type connector, or 0.1 inch pin header.
Power: 2.1mm barrel connector, or 2 pin terminal strip.
LEDs Power, Fiber activity(TX: red, RX: green), and RS232 receive


Distance: RS232: 10 to 100ft, Fiber: 125 to 225ft
Operation: Fiber to RS232, or Fiber to Fiber with RS232 tap
Format: Asynchronous data with any combination of bits, parity, and stop (auto mode)
Speed: Up to 115.2 Kbps
Environmental: 0C to +70C ambient, 10-90% RH(non-condensing)
Supply Voltage: 8 to 15 VDC Provided by external power source
Power: Under 1/2 Watt(typical) + external load
Size: 2.50" X 2.00" X 0.9" (PC Board), with connectors: 2.50" X 2.50"
Mounting: 4 Holes at 2.00" X 1.50" (built-in standoffs for #6 hardware)

Options and Ordering Information:

VLF232: $139.00 ea. (Circuit board only)
Enclosure: $8.00 ea. (small)
Data Cable: $7.50 ea. (RS232, 7 ft., Specify DB9F-7 or DB25F-7)
Power Adapter: $8.50 ea (wall wart type which meets California,
and most world wide safety and efficiency standards)

This is the complete order number for the VLF232 with all available options:

VLF232 with all options (enclosure and power adapter): Order Number: VLF232-BPS @ $155.50 ea. (Qty. 1-9)

Need a different configuration or more information? Give Ron a Call at 513-874-4796 or 513-638-0228(Cell)

Webstore: VLF232

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