Been asked by my old boy to make a circuit to flash a dummy methanometer, for a talk he is doing.
What he wants, 6 leds to flash all together once about every 10 seconds.
Looking around my bits I have
15 5mm red leds,
Lots of capacitors various values
Lots of resistors various values
10 555 timer chips
Some transistors both pnp and npn
Should be able to rob a 9v battery terminal from something.
Can any knock me up a circuit using the above parts and I'll make it and keep him off my case
The led values are
Forward voltage 1.8-2.1v
Forward current 20 ma
Reverse voltage 5v
Reverse current <=10ua