A previous Design Idea describes an astable multivibrator that gets hysteresis from the positive feedback stage using a technique you can characterize as positive-capacitive feedback (Reference 1). It ...

Here is a simple frequency doubler circuit that produces a square wave output with a precise 50 percent duty cycle. There are similar circuits in the literature [References 1, 2, 3] which require ...

In frequency counters, the gating time allotted for counting is often too short to resolve low frequencies. A phase-locked loop could be used to multiply the input frequency. But in some cases, the ...