SOUTH PORTLAND – The prototype doesn’t look like much – a plastic box connected to a circuit board with wires. But its inventors say the rough exterior belies the brainpower behind the device.

This equipment can detect metal, radiation and 80 types of explosive and biological compounds. Its developers say the $200,000 prototype could evolve into a new generation of remote-control sensors to thwart terrorist attacks.

This is the ambition of a 4-month-old company called Detection Technologies.

Aided by a $10,000 matching grant from the Maine Technology Institute, the three-person enterprise has recently built a rough model for its product called NEWS, or Networked Early Warning System.

The company is now seeking a patent and new technology grant from the Federal Aviation Administration. The company hopes to attract interest from the government and private companies and to begin limited production of the NEWS system in South Portland in late September.

Other companies also are working on improved sensors, but Detection Technologies says the NEWS system fills a void in what is commercially available and will appeal to customers looking for a more comprehensive approach to security.

The metal detection and scanning kiosks at major airports aren’t designed to sense bombs or other chemical threats, said Jim Plunkett, vice president for sales and marketing. The company says a comparable NEWS system unit can pick up the presence of metal, bomb material and radioactivity for roughly a tenth the cost.

Lawyers have told the company not to discuss details of how the unit actually works, although it involves proprietary software and technology for taking air samples.

The idea for the NEWS system sprang from discussions last year between Rand Stowell, president and founder of the company, and Roger Pience, the vice president of technology. Stowell had been president of United Timber Corp., a Dixfield forest products company. Through that association he created Predictive Control Systems, which uses software for process control in the pulp and paper industry. He also started Watson Technologies, which was developing equipment for cable television.

Pience, then an engineer with Watson Technologies, was talking to Stowell about other detection capabilities they might develop.

The discussions were conceptual until Sept. 11.

The government’s new Transportation Security Administration is now working with other companies on a pilot program to broaden the use of bomb detectors at commercial airports. The goal is to screen all checked bags by Dec. 31.

Although there’s been public interest in bomb and metal detectors at airports, the potential for private sector sales may be limited, according to Bill Zalud, editor of Security Magazine in Chicago.

The magazine surveyed thousands of businesses and government agencies after Sept. 11, and found that only 4 percent planned to install bomb or metal detectors. Twenty-four percent, meanwhile, were interested in video surveillance, considering it more affordable and effective.