555 and 9v batt.

Thread Starter

adamclark

Joined Oct 4, 2013
472
ok so I used this schematic and it oscillates fine, I cant find in marsdens blog or the other one the place to put the transistors in but Ill figure that out. My main problem right now is the LED that goes straight to ground is much brighter than the one that that gets its ground from leg 3 of the 555 when its low. Ive used the same value resistors. How would I get them the same brightness? When I have them flashing fast it almost seems like one is flashing faster than the other because of the brightness..
 

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Thread Starter

adamclark

Joined Oct 4, 2013
472
how would I change the amount of time the LED's.. its like the one that goes straight to ground stays on longer than the other.. the timing is not equal
 

Thread Starter

adamclark

Joined Oct 4, 2013
472
ok,, that's figured out.. the resistor values between legs 6-7, and between 7-+ have to be the same to get the timing right.. now just need to figure out the transistor(s) to hold the 500ma current and I can build this and finish the project.
 

Thread Starter

adamclark

Joined Oct 4, 2013
472
success, I have the transistor in the circuit and all 20 LEDs are blinking alternately.. Altogether it is pulling just below 100ma. So with that said, I didn't even need the transistor since the 555 can do 200ma right or does the transistor actually make it 100ma? Should I draw a schematic to post for others to use?
 
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