A PCB Interface for Using the IBM-PC as a Frequency Counter in Computer-Aided Testing (CAT) of Microwave Oscillator Stabi1ity

In this paper we describe a means of usinq an IBM-PC in computer aided testing (CAT) of the frequency stability of a microwave oscillator. Both long term stability (drift) and short term stability (noise) results are given for a commercial oscillator (Vectron CO-371B) operating at 475 MHz. The short term stability was characterized by specfying the noises that accompagny the oscillation for the Fourier frequency range, frequency counter for gathering the experimental data, as a data processor for frequency stability calculations, and as a word processor for both text and graphics.