The following schematic is for UM66 or BT66 musical IC. You need very few components to make this circuit.
Pin configuration for UM66 is given below:

Zener diode rated 3.3V maintains the required 3.3V for UM66 IC. The output from Vo of UM66 is amplified by BC547 transistor.

Click on the video to see the output


  1. Hi,my name is Satish. i just got on your site and to my great surprise your site is very good. i mean it is very explicit. it leave nothing to my imagination it’s really a great site for me. i am beginner in this field and i greatly appreciate your site. well can you help me by showing me how to convert a small voltage let say 3-9v into 220v.


  2. i am working on doorbell project . i also need loud music.Can you please send me that cirucit diagram .do i need to use same speaker as specified in ckt(wattage,resistance) or is there any substitutuion or that.


Please enter your comment!
Please enter your name here

6 + one =

This site uses Akismet to reduce spam. Learn how your comment data is processed.