Electronic projects

Description:
This circuit uses the Holtek HT2884 IC to produce 8 different sound effects.

Circuit diagram

Notes:
All sound effects are generated internally by the HT2884 IC. Power is a 3 Volt battery, but the IC will work with any voltage between 2.5 and 5 Volts. Switch S1 is the on / off switch. The output at pin 10 is amplified and drives a small 8 ohm loudspeaker. Pressing S3 once will generate all the sounds, one after another. S2 can be used to produce a single sound effect, next depression gives the next sound effect. There are 2 lazer guns, 1 dual tone horn sound, 2 bomb sounds, 2 machine gun sounds and a rifle shot sound. Standby current is about 1 uA at 3 Volt, so battery life is very economical. The IC may be obtained from Maplin Electronics order code AZ52G.

author: Andy Collinson
e-mail: anc@mitedu.freeserve.co.uk
web site: http://www.zen22142.zen.co.uk