60Hz Square-Wave Generator Circuit
This generator circuit uses an overdriven amplifier to produce a 60-1 Iz square wave from the 60-Hz ac line....
Siren Oscillator Circuit
A CD4093 chip and a few components make up a siren oscillator, which drives power MOSFET Tl. 4 speaker is driven directly from this device. ...
Space Age Sound Machine Circuit
The space-age sound device uses a 556 dual-times IC to produce a phasor sound. That IC is actually two 555 timer ICs in one 14-pin package, as shown in the sch...
Pure Sine-Wave Generator Circuit
A TTL counter, an 8-channel analog multiplexer, and a fourth-order low-pass filter can generate 10- to 25-kHz sine waves with a THD better than -80 dB. The cir...
Sine Wave Generator Circuit
In this circuit, a square wave is filtered by a high-order low-pass filter so that a -3-dB frequency will eliminate most harmonics of the waveform. As a result...
Simple Sine-Wave Generator Circuit
A 555 timer operating in the astable mode generates the driving pulses and two 4518 dual BCD (binary coded decimal) counters provide the square waves. A TL081 ...
Battery Powered Sine Wave Generator Circuit
The quality of the sine wave depends on how closely you match the components in the twin-T network...
Wien Bridge Sine Wave Oscillator Circuit
This Wien-bridge sine-wave oscillator uses a 2N3819 as an amplitude stabilizer....
Highly Stable 60Hz Sine-Wave Source Circuit
A highly-stable 60-Hz sine wave can be delivered with this circuit, which offers a different and much simpler approach to gaining a stable amplitude....
A Shortwave Pulsed-Marker Oscillator Circuit
A useful marker oscillator can be made using an NE555 to pulse the oscillator at an audio rate. This makes it easy to find the signal in the presence of interf...
6.5Mhz Vfo Circuit
Fixed-value capacitors are disc ceramics. CI, C4, C5, C6, and C8 are NPO ceramic or polystyrene. C2 is a 25-pF ceramic trimmer and C3 is a 15- pF miniature air...
Cmos Piezo Driver Using 4049 Circuit
This circuit uses a 4049 IC to drive a 2N2222 switching transistor....
Cmos Piezo Driver Circuit
A CMOS-gate and transistor buffer can be used as an effective driver...
Ultrasonic Pest Repeller Circuit
This circuit uses two transistors and one IC (555 timer IC) to produce a pulsating ultrasonic frequency. Transistors Ql and Q2 are connected in a direct-couple...
Pest Repeller Circuit
The two timers in the bug repeller have some interesting characteristics. Roth of them have their thresholds externally set; the oscillator on the left...
4093 Cmos Vfo Circuit
Two gates of a Quad 4093 are used in an astable multivibrator. CI is a three-gang 365 pF variable capacitor with sections paralleled....
Simple Audio Test Oscillator Circuit
An 88-mH surplus telephone toroidal coil is used in a 1-kHz oscillator. Up to 8 V p-p into a high-Z load is available. ...
4093 Cmos Astable Oscillator Circuit
Two gates of the Quad 4093 are used to make an oscillator. R,t: can be from about 5 kft to around 10 . Cx can be from about 10 pF to many, the limit being set ...
Variable Duty-Cycle Oscillator Circuit
Using a potentiometer and steering diodes, this 1.2-kHz oscillator will provide 1 to 99% duty cycle. Vary CI to change frequency....
Wien-Bridge Audio Oscillator Circuit
For variable-frequency operation, Rl and R2 can be replaced...