mmk so i have an ingenious plan to custom build a switch that turns something on, then off, then on again. preferably timed like one of those lawn watering things. i need to fine tune the on/ off /on

you'll see why when it's done.:tooth:

i need to know if something is done like it already. if not i will make it myself. shouldnt be hard, but it wont be pretty.

\thanks for any help. will update when done

something similar to this i speculate: http://www.quasarelectronics.com/ci0021.htm

been a while since i've done microelectronics though. and i'd still need to keep it from going 'off' again until power to the whole unit is disrupted.

basically i want to put this between a switch and a device. the device needs to auto-reset itself. then when it's off. it needs to be able to do it again:tooth:

You could use a 555 timer circuit and have the output control a transistor as a switch; if you need to control an AC or high current device, just wire the output (through the transistor) to a relay.

I'll have to dig up some circuits for the 555 timer, but with the proper resistor selection you can control the duration for which it's on and off.

What are you switching? (AC/DC, Voltage, Current)
What range of On/Off/On times are you after?
Will a switching relay be OK or do you want silent operation?
What will the circuit be powered from?

Can you provide a short explanation of what it needs to do.

I may be able to help.

Regards

Paul

weellll

it will be inside a computer so, it can be powered by molex for either 12v or 5.5v.

preferably a switch would trigger a relay to say on, off at this time, on again until i lose power (from said power supply or whatever); on for about 5 seconds, off for a second or less (essentially a restart) and then on again for ever until user input. If it helps we could somehow have it connect to the reset terminals to basically electrically push the reset 'button' :ground the reset wires for a second.

i want to put this timing device between the case power button, and the motherboard connection for the power on pins.

thanks for the tips sofar guys:tooth: like i said, im rusty and was never great at coming up with circuits, but i can solder good still

anyone? it'll be a great cure for some problems. i'll elaborate more when it's done :tooth::tooth::angel:

If you can provide more details on exactly what you're trying to achieve, we'll be better able to recommend an appropriate solution.

Anything of use here:

http://ourworld.compuserve.com/homepages/B...htm#555mono.gif

The 555 Timer Mono Stable (One Shot) Circuit perhaps?

If you need it to do anything slightly different I could possibly help.

Regards

Paul

that mono stable sounds about right.

i'm trying to put a circuit between the power_on pins of a motherboard, and the actual case power button, to turn the computer on for maybe 5 seconds, and reboot it. basically....

the reason? well i found out that it can cure cold bugging cfx3200's. at least some of them, like mine. I have been testing the method of letting it turn on for a few seconds, then restarting it. no more problems.

it would add a few seconds to boot time, but who cares if the board works :angel:

rhkcommander959

Did you get any further with this project. Need any help with the electronics?

Regards

Paul

talked to my old micro-electronics teacher, he's gonna help me set the circuit up. Ought be a good start to get me refreshed on circuitry!

been testing my method and so sofar the testing is successful. hopefully i'll have results next week:angel:

thanks guys!