Question about Roland 606 schematic
The corresponding signal can be found here
606 schematic http://machines.hyperreal.org/manufacturers/Roland/TR-606/schematics/roland.TR-606.schem-5.gif

It's 'leaving' right of D1, below the text "IC 1 HD14584B" and 'entering' where you highlighted it.

Below is indicated where the components are that are referred to in the text above. They are probably mounted for some types and left out for other types.  



They can be found in the same sheet where you found the hihat part.
http://machines.hyperreal.org/manufacturers/Roland/TR-606/schematics/roland.TR-606.schem-6.gif