An amplifier is a type of electronic test equipment that amplifies radiofrequency (RF) and microwave signals using the antenna. Amplifiers are ideal when used for electromagnetic interference (EMI) testing, cell phones, microwaves, radio communications, and other such applications. Engineers involved in the design, installation, maintenance, and testing of circuits can use an amplifier for laboratory applications that need moderate power output, high gain, and instantaneous bandwidth. ValueTronics has top-quality new, used, and refurbished amplifiers for sale.