Keen eye, soft touch needed to work with glass wires
December 5, 2006
TOBYHANNA ARMY DEPOT, Pa. (Army News Service, Dec. 5, 2006) - Paul Baumes, an instructor in the technical development division here has trained to date more than 100 Army civilians how to build and repair fiber-optic cables capable of transmitting gigabytes of information in the form of light.
One fiber-optic is made up of a strand of special glass as thin as a human hair and can transmit more data faster than copper wires.
"I've been training field service representatives for the Army Tactical Operations Center system, 'Reach Back' individuals and depot employees who asked for the training," Baumes said. "'Reach Back' individuals are those who fill a field service representative's slot at a forward repair activity when the representative deploys overseas."
The 40-hour course comprises hands-on instruction and practical exercises in how to construct fiber-optic patch cords using various connector ends and second generation tactical fiber-optic cable assemblies, called TFOCA IIs.
A TFOCA II is a fiber-optic cable composed of four fiber-optic connectors mounted into a plug or receptacle. Patch cords are fiber-optic cables used to link equipment to a fiber-optic network.
There are two primary types of fiber-optic cables, multimode and single mode. Multimode fiber-optic cables use light emitting diodes to transmit data via multiple modes of light simultaneously.
"Fiber-optics is the wave of the future," Baumes said. "It's being used more and more as the demand for real-time data transmission continues to grow on and off the electronic battlefield."
Fiber-optics training includes termination techniques, fiber-optic connector polishing, testing of complete cable assemblies and troubleshooting faulty cables.
Termination techniques entail constructing four-channel cables with specially designed termini built specifically for TFOCA connectors and following procedures to ensure fiber-optic cables meet specifications.
"Connector polishing means literally polishing the end of a fiber-optic strand. Once construction of a connector is accomplished, there is excess fiber strand that is scribed or etched so excess glass can be removed with minimal damage," Baumes said. "The end must then be polished so it transmits light beams as efficiently as possible. Polishing is done by affixing the cable end into a 'polishing puck' and rubbing it in a figure eight motion over polishing paper."
The paper has very fine grits, from 12 microns to .3 microns, and can be aluminum oxide or diamond paper. A 400X power microscope is mandatory to check the polished end of the glass strand.
Baumes noted scribing and polishing to be the critical parts of the process because signal loss will be significant if these steps are not precisely followed.
"The glass is very easy to break," said Michael Ordonia, who serves as an electronic equipment specialist at the forward repair activity at Fort Lewis. "If you break it, you have to start all over."
Ordonia took the training to make reset and repair of TOC vehicles easier since fiber-optics is used throughout the vehicles. He hopes to show Soldiers how to make emergency repairs.
Baumes said the training is not difficult for students, but the work demands patience due to the delicacy of the components involved, plus the need for precision and good eyesight.
"If one of the four connectors in a TFOCA II is broken or incorrectly constructed, the entire connector assembly must be redone," Baumes said. "The work is time consuming and repetitious.
"The construction process is very sensitive and requires a delicate touch and a good sense of feel to prevent the need for rework. It's an art form that requires repetition in the process to be successful on a regular and consistent basis. It just takes time to learn how to handle the glass," he said.
Tobyhanna Army Depot is the Defense Department's largest center for the repair, overhaul and fabrication of a wide variety of electronics systems and components, from tactical field radios to the ground terminals for the defense satellite communications network. Tobyhanna's 4,400 employees support all branches of the Armed Forces.
(Anthony Ricchiazzi serves with Tobyhanna Public Affairs.)