Christmas melody generator ic trusemi m995c 4 an ic which can produce three melodies requires only a 3v battery and a small 8 omega speaker such as 35 0047 ndash see pa amp audio video section to make a working project by making connections to separate input pins each melody may be triggered individually additionally an input pin is provided that will play all melodies in sequence the tempo of the melody may be adjusted to play faster or slower by varying the value of r sub osc s