Telonic Berkeley Corporation was founded in 1958 as a source of high-tech test equipment, custom radiofrequency (RF) devices, and microwave components. The company has long since been dedicated to producing ultra-high-quality products for engineers, technicians, and other professionals in need of the tools to safely and effectively test, install, and handle electronic equipment. Telonic has an extensive product line of attenuators as well as sweep generators and filters. In 2009, new owners took over Telonic to revamp the company as a top manufacturer on the market. Today, consumers can purchase new, used, and refurbished items developed by Telonic at ValueTronics.com.