dwwilson66 wrote:Just double checked voltage on the green LED. First, you'll have to forgive me; I can't tell a cathode from an anode once it's soldered in place...and it's tiny enough that I can't really tell or feel which side is flat...but my gut reaction tells me that the (-) side is the flat one on this...which would have it installed properly.
Yes, the flat (cathode) should be on the (-) side.
dwwilson66 wrote:Anyway, when the switch is depressed, I get 3.1V with my black probe on the black wire, and my red probe on the side of the LED closest to the red wire. 0V when the switch is open. I'm having a hard time tracing the circuit after that...I think I go to R5, then IC Pin6..?
That sounds mostly OK. The switch pulls the chip's reset line low when you press it. That should cause the chip's port pin to go low, which will light the LED. Try touching up the solder on the LED leads. If that doesn't work, then I suspect your LED has been transformed into a DED. If you have a spare LED, try replacing it. Otherwise, email firstname.lastname@example.org
for a replacement.