Higher-Frequency Transformers - Introduction

In Amplifier Circuits - Introduction the influence of low-frequency performance on size was mentioned. If high transformer OCL is required to maintain good low-frequency response, many turns or a large core are necessary, either of which limits the high-frequency response. But if the amplifier frequency range is wholly composed of high frequencies, this limitation is in large part removed. For example, in a power-line carrier amplifier, the frequency range is 40 to 200 kc. It is then only necessary that OCL be high enough to effect good response at 40 kc. This is a great help in designing for proper response at 200 kc, and makes possible the use of laminated iron-core transformers for these and higher frequencies.