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Friends take an interest try build Tone Burst Generator be simple is. Try this circuit like sure because use IC 555 , highly popular again. Assure that not sure difficult press the the secretariat of the senate S1 a loudspeaker will utter to come out immediately. When liberate S1 already the sound may loud again [...]

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 [...]

Here is a circuit mini Organ, It very easy circuit and low cost.
The important part of the circuit is 2N4891 FET Transistor,It is Tone Oscillator Generator.
R1-R9 is Control Tone sound music,To change value C1 ,so output change Frequency all range.
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