I designed an alarm clock with random ON/OFF times to make a house look like it was occupied. Attached is the schematic and picture of the PCB. I sell these as a kit, but I see no reason why I cannot email you the code if you buy the kit, so you can modify it to suit your needs. It is based on a PIC and written in C. Please let me know
tx for ur diagrams, but i think this circuit is juz to complicated for newbie like me to modify. and, wat i plan to do is to include an alarm clock to my 18f452, which i think this might not suitable for my applications, especially when i need to explore the code. i juz simply donot have enuf time. =X btw, appreciations and tx.