Timer 30 to 90 seconds

Can I use any of your timers to give me a variable timer from 30seconds to 90seconds to operate a small device.

Would anybody like to help me with this problem,at a fee.

Posted by eddy (eddylevin@blueyonder.co.uk) on 23/11/2007, at 09:06 GMT

Timer 30 to 90 seconds

The problem here is to obtain sufficent range, necessarily using a megohm range potentiometer of tolerance plus or minus 20%(not accurate but could be solved by switched resistor ranges)and an expensive low leakage electrolytic (usually tantalum bead)capacitor. Formula reminder T= 1.1*R*C.

Posted by varient412 on 15/02/2010, at 19:00 GMT