Yes, normally they are one. Even the metallic part on your throttle is part of the (almost unobtainable) bowden cable coming from the vacuum unit in the top left of the picture.
You need to find some way of connecting those again (parts from a bike brake cable ending can help) so that the cable has no slack but is also not 'pulling' on the throttle when idle (or off).
Another thing I needed to do is to replace a few capacitors on the board especially the 2 'frako's' in the middle of the board, 47 uF at 16V were fried and the reference capacitor that holds the reference speed in the lower right of the board (0.1uF) with 'one leg up' to the FET transistor in the lower right corner. (The C5 in my temp
schematic here - I have a better one now with some mistakes eliminated).
Checked out all the wiring and the Ohms on the vacuum (pin 3 to pin 7 : 11-17 Ohms) unit and it works again in my case and pretty stable.
If you need further help, let me know.
It is a pretty simple system and perfectly user-fixable.
Regards,