On/Off Alternating Direct current other than a power switch?

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Biasless
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Hello,

I would like to know if there is a part I can buy that will alternate my dc power circuit on/off at short intervals automatically


All help much appreciated,
Cheers,
Nick
 
Biasless said:
Hello,

I would like to know if there is a part I can buy that will alternate my dc power circuit on/off at short intervals automatically

All help much appreciated,
Cheers,
Nick

yes you could with an oscillator or timer
Tell us more about what you are trying to achieve so we can help you better

Dave
 
Thanks for the help,

trying to have a electric magnet turn on/off at a regular interval

So the magnet would turn on for a second, then turn off for a second
repeating that indefinitely
 
ok you could use something like this...

Circuit schematic of a 555 timer astable oscillator driving a relay and electromagnet through a BC337 transistor, with a 1N4001 flyback diode across the relay coil, a 100uF and 0.1uF supply decoupling, +12V supply and 0V ground, and the note: Osc freq needs to be 2Hz and 50% duty so 1sec on 1 sec off. Freq = 1 / 1.386xRxC


see how you go

cheers
Dave

Yeah, sorry abt the broken link, the net crashed as I was trying to do the post
and had to wait till now when i got home from work to repost.
 
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  • Circuit schematic of a 555 timer astable oscillator driving a BC337 transistor and relay with a flyback diode, switching an electro magnet from a +12V supply; labelled Osc freq needs to be 2Hz and 50% duty so 1sec on 1 sec off, Freq = 1 / 1.386xRxC.
    Oscillator 555 and relay.gif
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now the only thing you haven't said is what voltage you are running the electromagnet from ?

I have assumed 12V. if its different then the top of the relay contact can be removed from the +12V and the bottom of the electromagnet removed from the 0V and they can be put across the separate power supply for the electromagnet

Dave
 
Thanks for all your help :)

i'll start reading up on understanding circuit diagrams