Simple 20 Sec Timer with fade off

155

02:12:34

Simple 20 Sec Timer change 220uf or 42k for different times the time constant equals 2*R*C where R is 42K resistor and C is the 220 uf 

If you don't want it to fade remove 100uf and reduce PNP collector resistor  to 10k also reduce 4.7k to 1k for more  load current 

published 10 years ago

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