In my class today, I hooked a 555 in astable mode to an o'scope.
Before powering up the scope, I centered the trace. After powering
up the 555 I noticed the output from pin 3 was going from +v to -V (I
didn't check the voltage scale, so I don't know how large V is). I
don't understand why that happened. I should have gone from 0V
to +V.
Am I missing something?
Paul
