CMOS SCHMITT TRIGGER IC MAKES VCO

Square-wave generator with 555

A single timing resistor ensures that the output is a square (50% duty cycle) wave at all frequency settings.

Triangle-square wave oscillator

This circuit generates simultaneously, a triangle and a square waveform. It is self starting and has no latch up problems. IC1 is an integrator with a slew rate determined by CT and RT and IC2 is a Schmitt trigger. The output of IC1 ramps up and down between the hysteresis levels of the Schmitt,...

Triangle-square-wave-generator

This circuit uses a positive-feedback loop closed around~a combined comparator and integrator. When power is applied, the output of the comparator will switch to one of two states, to the maximum positive or maximum negative voltage. This applies a peak input signal to the integrator, and the...

Big loop oscillator

L1 is a loop of 10 to 20 turns of insulated wire with a diameter anywhere between 4" to 4'. Oscillator frequency (7 to 30 MHz) shifts substantially when a person comes near or into the loop. This oscillator together with a resonant detector might make a very good anti-personnel alarm.

Square-wave oscillator

This project is a piece of test equipment. It`s a square wave oscillator with 6 selectable frequencies from 1Hz to 100kHz, incrementing in decade values. It`s most useful application is as a Signal Injector for radios and TV`s. A square wave is the most suitable for testing the IF (Intermediate...

4-Decade Square-Wave Generator

This circuit will generate a square wave of 2 Hz to 20 kHz. The circuit uses an op amp in a relaxation-oscil

Rounding Off a square wave

To "round" your square wave, you need to integrate it twice; once to produce a triangular wave, and a second time to produce a parabolic waveform. (A parabolic wave looks pretty much sinusoidal.) You can do this passively using a simple network such as the one shown below. Let R2 = 10*R1, and let...

Frequency Divider

This circuit will divide the frequency of a TTL compatible square wave signal by a factor from 0 to 999. The circuit comprises three decade counters IC1 to IC3 and a few NAND gates. The three 7490?s are cascaded and count is the input signal. When the desired and count reached all the inputs of...