Simple-touchtonetm-generator


Posted on Sep 13, 2012

The oscillator is a Motorola MC14410CP chip using a 1-MHz crystal. The chip generates both the high and low tones, feeding the energy to the amplifier through 1-K resistors and the 1-I`F capacitor. Values for the output resistors can vary from a few hundred 0 to about 60 KO. The value of the resistor shunting the crystal can vary from about 3 to 15 MO.


Simple-touchtonetm-generator
Click here to download the full size of the above Circuit.

The amplifier consists of an LM-380N.




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