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By Jack McCarthy, Belden Wire & Cable

This month marks the silver anniversary of a major fiber event, an event that came about because of the vision of several people. Cod liver oil and a flashlight also contributed.

This month, cable celebrates the 25th anniversary of the first commercial deployment of fiber optic technology. This deployment, the first by any communications sector industry, was made possible through the hard work and dedication of many companies and individuals. What were the events surrounding the July 8, 1976, transmission?

In the mid-1970s, a number of companies were tracking the research and development taking place at the technology lab of Corning Glass Works in Corning, New York, an International Telephone & Telegraph (ITT) facility in Roanoke, Virginia, and at Bell Labs in Norcross, Georgia. As the physicists and scientists developed glass fiber with attenuation levels of less than 20 decibels (dB) per kilometer (3280 feet), they made possible the practicality of communicating over ultra-pure filaments of glass fiber. The long- sought 20 dB breakthrough meant that 1 percent of the optical signal launched over the fiber would be available at the output end of that kilometer.

Several manufacturers of coaxial cable, as well as a number of connector manufacturers, had been tracking the development of this new technology. Each had to analyze what impact, if any, fiber optic communications might have on the sales of their current product offerings, and each had to determine what new markets might become available. They knew they would have to invest in research and development of new cable designs, and that they would have to develop new techniques to terminate those hair-thin fibers.

Major decisions regarding capital expenditures for further development of this technology would have to be made, but only after the technology could be proven in some of the applications for which it had been envisioned, such as cable television, telephony and computers. All of those industries could use the bandwidth that fiber promised, and finding someone to partner with on research was one of the many hurdles to overcome.

Fortunately, our New York-based sales representative told me that a gentleman named Bill Bresnan, president of the Manhattan TelePrompTer system, was a visionary who might be willing to work with us in implementing fiber in his system. I had several phone conversations with Mr. Bresnan to explore this proposal, and finally had the opportunity to meet with him in the Admirals Club at Chicago's O'Hare Airport.

We discussed what we envisioned as a logical plan to see if those tiny glass filaments could be protected adequately from wind, moisture and temperature cycling through proper cabling techniques. We also needed to be assured that the cable design could withstand the rigors of installation. Mr. Bresnan asked that we work with his chief engineer, Ron Simon.

Belden Wire & Cable had been working to secure a relationship with a manufacturer of glass fibers, and ultimately made contact with a small company in East Orange, New Jersey. This was a start-up by two former Bell Labs employees--Frank W. Dabby and Ronald B. Chesler--who were involved in fiber development. The pair subsequently became licensed to produce glass fibers under the Bell Labs patent, and used the name Fiber Communications, Inc.

Dabby and Chesler were entrepreneurs in the truest sense of the word. They had founded their company with the belief that optical communications would be a commercial success, and they were extremely excited about the opportunity to work with us in putting our plans with Bill Bresnan into action.

Several months after meeting with Bresnan, Belden's Senior Product Development Engineer, Bob Sharp, and I were back at O'Hare. We had three tickets to New York City: One for Bob, one for me, and one for the reel of fiber optic cable we were taking on the first leg of an historic journey.

Phase one

After arriving in New York on a clear and warm Monday in early May, 1976, we traveled out to the TelePrompTer headquarters to meet with Ron Simon. Ron had arranged for several installation crews who would be involved in the first phase of our experiment, pulling the cable through existing duct under the streets of Manhattan.

A parade of three TelePrompTer trucks, followed by our rental car containing the reel of cable, arrived at our test site. It did not take the crews very long to go about opening several manhole covers and setting up the de-reeling stand from which this strange "glass cable" would be pulled. Radio checks were made with the crews at each of the three manholes beyond the point at which the cable would be tied to a stringer and pulled through.

Because the duct had existing coax cables already installed, we anticipated that the cable would get stuck at some points along the route, and this did occur. The installation crews were instructed to handle the cable in the same manner they would handle a coaxial cable that was stuck.

Once the cable was pulled to the furthest manhole, a very sophisticated continuity test was performed. Ron Simon got on the two-way radio and asked the crew at the far end to call him back if they saw light coming from the fibers when he coupled his flashlight to the cable end at our starting point. An obvious sigh of relief was heard shortly after the radio cracked: "We can see light on all of the fibers."

That success led the participants to implement the next phase, carried out on July 8, at the TelePrompTer headend facility, located on the second floor of a 38-story high-rise building. Bob Sharp and I met Ron Simon, along with Drs. Dabby and Chesler, and reviewed the installation plans. Crews took the cable to the top of the building where it was deployed, feeding downward from the microwave room. The microwave room would receive the HBO signal and transmit it to the headend room. Dr. Dabby had arranged for the optical transmitter and receiver, as well as the connectors with fiber pigtails. All of the requisite materials were in place and the cable was fed down through an airshaft in the building. As I remember, we weren't concerned about having a riser rating on the cable because the National Electrical Code (NEC) didn't incorporate that requirement at that time.

Once the Belden-produced six-fiber cable was in place, Dr. Dabby handled the interfacing of the equipment in both the microwave room and the headend in order to convert the HBO signal from an electronic frequency to optical energy. After the optical signal was received at the headend room, it was reconverted to the electronic frequency that allowed it to be distributed back out to the system's subscribers.

The trickiest part of the installation was getting the core of the fibers in the cable to align perfectly with the core of the fiber pigtails. These had been epoxied to the connectors that would mate with the optical transmitter and receiver. Without proper alignment along the x-, y- and z-axes, the signal would attenuate at the point of the fiber interfaces and be lost. A quick fix to our dilemma was a visit to the local drug store where I purchased a bottle of cod liver oil, which we used as an index-matching fluid.

Unforgettable moment

The feeling that came over me when the HBO presentation came up on the receiver was something I will never forget. I recall saying to myself, as I stood there and watched history being made: "I hope the TV show 'You Are There' will make a comeback someday. I wonder who will play my part?"

The first fiber optic installation in cable television history was the result of the vision of a number of people. On one side of the equation, Bill Bresnan and Ron Simon had the vision to see the potential of fiber for their industry. The technological capabilities of Belden Wire & Cable and Fiber Communications' personnel combined to prove that what once had been a dream had become a reality.

When all of these elements were added together, the sum was success. That success has translated into miles and miles of fiber optic cable being deployed in all modern communications systems today. It doesn't seem possible that it has been only 25 years.

Some personal footnotes to this story: Fiber Communications, Inc., was acquired by Times Wire & Cable in the late 1970s and a new entity called Times Fiber Communications emerged. I have personally lost contact with Bill Bresnan, Ron Simon and Drs. Dabby and Chesler, but I hope they are enjoying good health and happiness. Bob Sharp retired from Belden several years ago, but I do get to see him at the annual gathering of the Belden Chicago Chapter "25 Years" Club.

As for me, I continue to represent Belden, and I am able to participate in the development of advanced communications cables for the wireless industry, as national account manager for Motorola.

Jack McCarthy is national account manager, OEM Group, with Belden Wire & Cable. He may be reached by e-mail at .

 Back to July 2001 Issue

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