Different Alarm, Horn, Gong etc.

Electronics Infoline Web

Modular Burglar Alarm

http://www.mitedu.freeserve.co.uk/Circuits/Alarm/mba.htm

http://www.mitedu.freeserve.co.uk/Circuits/Alarm/pad4.htm

http://www.mitedu.freeserve.co.uk/Circuits/Alarm/alarm.html

http://www.zen22142.zen.co.uk/Circuits/Alarm/csza.htm

http://www.mitedu.freeserve.co.uk/Circuits/Switching/keypad.htm

http://www.mitedu.freeserve.co.uk/Circuits/Alarm/Galarm.html

http://www.zen22142.zen.co.uk/Circuits/Alarm/mba.htm

http://www.zen22142.zen.co.uk/Circuits/Alarm/Galarm.html