I wonder if it is the voltage drop that occurs when the pump starts that is triggering the timer.The voltage drop is 1.7V. I tried increasing the capacitor size on the 6V rail from 220 microF to 470, no go. I put 2 470's in series and no go.
It seems that the trigger of the 555 timer has to be better isolated. I am getting some good tips from the electro-tech-online forum mentioned in previous thread. I will do some experimentation and report back when I have a solution.
