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Many timers are there

simple with basic parts no IC =not there

The timer at low voltage =not there

Unless you get low voltage 555 you cant make .

Many parts of the world the special chips need 30days to reach .

So i tested the timer with FET and BJT pair.

Step 1: The Devices

The devices tested were TO92 packages , can be done point to point solder .

slight changes can allow relay trigger too .

Step 2: The Circuit Is ...

The FET is like a switch with gate getting a +ve , the lower 1m is to cancel internal capacitance effect.

The BJT is a very low voltage switch as the neno amps of charging for the cap makes it on. without the BJT part the FET is wired in ON mode and as BJT "eats " the GATE voltage as long as the capacitor charging. The cap can go 1000uf making 10hour or more time possible .!!!

Step 3: Build Proto ,conclusion

well the proto was a point to point test jig ..will post a superglued build

soon..

Bye

Step 4:

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