I breadboarded the 1st 555 to check what happens.
When I connect the power (12V), the OUT pin of the 555 rises immediately to 12 V. When I join the two long yellow wires, simulating the pushbutton action, the voltage drops to zero, for about 1 second. This would be exactly the opposite of what I wanted to happen.
I'm measuring the OUT voltage by connecting the (+) probe of the voltmeter to the (+) of the power supply and (-) probe to the OUT pin of the 555. If I connect the probes the other way around, I get the same readings but with the polarity reversed.
What am I doing wrong here...???
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