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Electrical Timer. I need a timer for a Halloween prop. Answered

It's a cadaver that trembles continuously. It runs on standard house current. I'd like it to tremble for only a few seconds at a time, then nothing for 10-20 seconds, then repeat.

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Jayefuu (author)2009-10-22

This page has a good tutorial on astables using a NE555N IC. Since you want it on for a few seconds then off for a long time, you need to vary the mark (the time it's on for) to space (the time it's off for) ratio. All the equations are on the page in the link above.<br /> <br /> Reply if you need more help. :)<br />

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Re-design (author)2009-10-21

Google "555 timer circuits" and find one you like.  You should be able to use a relay to turn the house current on and off.

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