Free circuit schematics - wiparat.com

This is astable multivibrator circuit or Square-Wave Oscillator
or basic pulse generator it use op-amp IC-1458 is main parts and a few parts.
By have Vsat value size as same as with power supply voltage. The frequency Output set by value R1
and C1.
Frequency Oscillator output = 1/(2R1.C1.ln3)
The C1 capacitor to change capacitance per frequency value 1uF = [...]

Here is the tone generator circuit,it is small size.
I use IC digital Cmos 4011 quad NAND gate.
This will cause another NAND gate to pulse oscillater which will drive another gate to output a 1.3KHz tone.
The transistor provides drive for the 8 ohm speaker.
The IC 4011 ’s Input pin 1 for Control output tone generator, so [...]

This is a simple high pitch noise generator circuit. It has a timer oscillator with a frequency variable from 15khz - 30khz.
The circuit can be mounted in a plastic box like I have done. The good thing about high frequency sounds is that it is very hard to find where they are coming from. Also, [...]