FREQUENCY SWITCHING SPEED MEASUREMENTS USING A DELAY-LINE DISCRIMINATOR

Frequency switching speed (FSS) measurements around 3 GHz are presented, using a delay line discriminator (DLD). A relation is derived that governs the quasistatic condition for the transfer function of the DLD. Under the quasistatic condition, the transformation of the DLD output signal to the transient frequency of the input signal requires only harmonic functions in the mathematical transformations. An expression is derived for the signal-to-noise ratio of the measurement circuit's output signal, with examples relating to analog and digital oscilloscopes as recording devices. It is concluded that the DLD is a powerful and economical tool for FSS measurements.