Hi,There seems to be general agreement here, and I concur, that you probably damaged the 555 when you originally had it connected to the relay.
You have been asked twice whether you have swapped out the likely damaged chip. You have not acknowledged or answered that question.
Don’t know why people are continuing to offer suggestions at this point.
Bob
Seems like a poor choice to me:would like to use 1 PNP transistor instead of 2 NPN's.
but I need a transistor that can handle about 400mA of collector current as I will be connecting a small water pump there.
will "2N6107" be a good choice?



Hi,Seems like a poor choice to me:
View attachment 202816
View attachment 202817
View attachment 202818
Saturation mode characteristics are pretty vague. They assume a beta of 2.3, give horrible CE and BE saturation voltages, and don't give any graphs so you can interpolate parameters for your situation.
Have you considered a P MOSFET?
TIP30CCould you please suggest one?
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