DTMF (phone dial tone) To High and Low Outputs

You know when you push a button on your phone it makes a funny sound? That Sound Can Be Taken And Converted Into High and Low Outputs. For Instance If you Push The Number 5 On Your Phone It Puts Out A Unique Dial Tone And We Take That Tone And Make A Pin

Created by Jordan
Status: Active

DTMF (phone dial tone) To High and Low Outputs Step 1 of 1


Have any of you wanted to make a controller that is wireless and long distance? Well the best way of commuincation is through phones so why not use that to control your projects. Well you can by using the phone's keyboard we can wirelessly control any of your projects. Here's how you set it up:

1) Hook a phone 1 to this kit.

2) Call phone 1 with phone 2.

3) When you can "talk" to phone 1 start pressing buttons.

4) Each Button Can Control a Specific command.

Thats how simple this really is and this is how it works:

1) When the first ic (ic 1) in the kit recives a dial tone it will send a series of pulses to the next ic (ic2)

2) Then ic 2 will decode that series of pulses and make a specific pin high (on).

3) If a different tone is played the decoder (ic 2) will make the first tone's pin low (off) and turn the new tone's pin high (on)


Step 1

Take your pcb and insert all the resistors and diodes.

To make the layout easier put your ic's in place to line up the resistor and diode pins.

Solder Components

Step 2

Take your pcb and insert the crystal and the transistors.

Again put the ic's in place to line up the pins.

Solder Components

Step 3

Add the remaining components to your board and solder the rest of the components.

The input voltages are 6-18v DCbut i recoment 12v DC.


Useful Applications:

Remotely Turn on and off appliances 

or control a robot, a light, and anything that uses electricity.



For use to control high power appications use some 5-7v relays. :)