Except the diagrams I saw didn't look like the other in-game circuits I saw. So, I'm still unsure if those are diagrams or in-game implementations. If you know, please tell me.
A
→o * o→M O
o * o
B
The mechanical power goes in the first →, and the [M O] part is the output. A and B are the AND inputs. Gearboxes actually look like *, but o is also being used for gearboxes, albeit gearboxes that are just there to drain power.