Operation Terror

"First published in 1962, Operation Terror is a novel of how humans respond to the threat of an alien invasion. Lockley, who suspects that humans traitors may be involved in the alien attack, develops a portable device that deflects the alien terror beams with unforeseen consequences."@en
"When extraterrestrial monsters, abetted by human traitors, begin their conquest of Earth, the beseiged population races to develop a portable device that can deflect the alien terror beams."@en
"The mild-mannered surveyor Lockley is going about his business at a project site in Colorado when the unthinkable happens -- an object that seems to have originated from outer space crashes to the earth. This unusual event sets off a chain of increasingly dire consequences, and before long, it becomes clear that only Lockley can save the world from the impending alien invasion."@en