When working with electric network components, one can pick active signals with [Q] to quickly select them for setting them as input and output conditions on the combinator.
This seems to work for almost any signal, but there are a few that don't work.
In the picture below the ones that don't work:
- upper part of the screenshot below: few recipes don't yield in the recipe but in the resulting items
- bottom-left: fluid sources like oil patches and fluorine vents yield in pumpjacks
- bottom-right: some signals that are not [Q]-pickable at all