Logo RS485 Authority
Questions? Custom builds? We build and support all of our boards.
If you have a special application, we may already have a solution for you.
Give Ron a Call at 513-874-4796 or 513-638-0228 for additional information.


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

INTRODUCING THE SMFCOMX! Click here for more information.




What’s Special About RE Smith:

  • We engineer, manufacture, and test our entire product line in the Cincinnati Ohio area.

  • Many of our products were developed in response to a customer’s specific need.

  • Your feedback and comments drive us to improve the products and develop new ideas.

  • We want to hear about your communications problems. We may already have the solution.

  • Technical assistance and system design help is available at no charge. (513) 874-4796

  • Our products are at the South Pole, the bottom of the sea, the edge of space, and in between.

  • We ship small quantities of stock items the same day and larger quantities in a few days.

  • Our no argument warranty and repair policy will get you back up and running quickly.

What’s Special About Our Products:

  • We feature RS232, RS422, RS485, USB, and ethernet devices using copper and fiber.

  • Broad range of converters, repeaters, and I/O boards. Many are microprocessor controlled.

  • Unique rapid auto data direction control reverses a half-duplex channel without software or hardware intervention. This avoids data collisions and leading edge degradation.

  • Handles all serial data on a bit by bit basis. Compatible with all formats, data/baud rates, and bits per character. RE Smith devices will not limit your communication speed.

  • Extended range. Reliable operation at distances far beyond the conventional RS485 limit. Distances of 3 miles at 115.2Kbps to 8+ miles at 4800bps are typical.

  • High noise immunity. We employ transient suppression and 3KV galvanic isolation. Where advantageous, we feature dual isolation, and multi-level transient protection. If your system is unreliable, flakey, or blows up from time to time, you need to talk to us. Been there, done that!

  • Industrial strength: Wide power supply, temperature and humidity tolerance.

  • Easy hookup: Fixed/removable screw terminals, USB, RJ11/12/45, and barrel connectors.

  • Unlimited phone support. Schematics and data available on line. We’re eager to help.

What’s New:

  • Modular Fiber/copper converters, repeaters, distribution amplifier, monitor/tap point devices, sharing a common motherboard/platform. This provides a wide range of interface possibilities.

  • High speed 3KV isolated Converters and Repeaters capable of speeds to 10Mbps.

  • Extended range 3KV isolated high drive voltage(12-15V) devices using CAT-5/6 cable. Distances of 3 miles at 115.2Kbps to 8+ miles at 4800bps are typical.












RS485/RS422/RS232 Networks as God Intended Them to Be




Donna Schaller-Smith, October 26, 1947 to February 4, 2006


Mandy,  January 14, 1983 to May 13, 1997