Introduction
Most RF amplifiers have what has come to be known as“standard” 50Ω output impedance. The AR RF/Microwave Instrumentation model 350AH1 RF amplifier is unique in that its output impedance is typically less than 1Ω. With such low output impedance and a broad frequency range of 10Hz to 1MHz one might mistakenly make the assumption that the 350AH1 is merely a high-end audio amplifier. This amplifier however was not designed to be used in any stereo system. It was specifically designed as a very versatile and rugged bench-top instrument for lab use in R&D applications, product quality testing, magnetic research, and Electromagnetic compatibility (EMC) testing per MIL-STD-461F: CS101, CS109, CS114, RS109, DO160F sections 18 & 19, as well as many automotive EMC standards. The extreme rugged design ensures that the 350AH1 will deliver required voltage and/or current to any load without fear of amplifier shut-down or failure. This Application Note will explore the characteristics of this unique amplifier, cover methods of interconnecting amplifiers for enhanced performance, and discuss some of the applications addressed by this robust, versatile amplifier.