Welcome to this simple modification to allow a buzzer to be used with your DTMF global remote control devise.

Now if you would like to hear the tone from the buzzer when it is decoding the DTMF Tones then visit my You Tube page here.

1). I designed this modification to allow a buzzer to be used alone side the LED so now when the LED is decoding the DTMF tones by flashing on and off the buzzer will switch on and off at the same time.

Please note if you need more information to do with this design then visit my page here.

You can see more of my electronic designs on my electronics page here.

You can e-mail me here: Anthony@anthony-dacko.net

2). You should have know problem getting the parts for the add on sounder as they are all off the self components.

3). Capacitors are 100UF 35 volts or more order this on Ebay. 

4). The voltage regulator 7805 order this on Ebay. 

5). Transistor BC 639 NPN order this on Ebay. 

6). Relay used was a 12 volt version single pole.

7). If you want to use a 5 volt max buzzer but don't want to use the regulator then you can use a 3 x AA Battery Holder
Available with PP3 Clip connection order this from bits box: http://www.bitsbox.co.uk/batteries.html