hey guyz i am trying to build a circuit for generating time delay of 10s but the thing is i want to do it without using 555..is it possible.??how?i want to basically use it with a solenoid forflushing purpose
tnx

 

YES. Use a micro controller. PICAXE is a common one. Google them up and read all about them.

 

Of course, the 555 isn't the only timer ever produced: http://focus.ti.com/docs/prod/folders/print/cd4060b.html. You can do it with an RC circuit and a comparator (this is what happens inside a 555).

 

You will find a lot of time delay circuits you build out of just components have a slow on time, or at least I did....
Why not use the 555? just curious?

 

I have some nice time delay circuits that can go several minutes (max) using a j-fet, capacitors, and resistors, but I have no idea what input signal you want to use or what output voltage or current you need.

 

Back in the day, we would use a UJT and RC network.

 

oscillating the UJT to lengthen the time required to charge a cap?

 

oscillating the UJT to lengthen the time required to charge a cap?

UJT timer would trigger SCR

 

Oh. Using the UJT as a comparator (comparing the breakover voltage of the UJT to the voltage on a capacitor).

Thank you Bill.

 

Take a look here...... http://www.google.com/imgres?imgurl...a=X&ei=iPniTYeOAcm_gQeug5SQBg&ved=0CDMQ9QEwBA

 

That's what I was thinking. Hope my words weren't confusing to you. Thanks again.

 

Here's a discrete alternative. Nearly any small NMOS FET will work OK. None of the component values are critical here.