According to this page, the Hobbit / PA50 didn't get a battery and CDIgnition untill 1981 when the yellow color was dropped and bikes were red. .. So the wiring information in the manual g.b. linked won't be quite right.. The rest of the manual is very helpful.
"Here":https://www.mopedarmy.com/forums/discuss/download.php?f=6&file=1082480832_honda_pa50_1978_wiring_diagram.jpg is a 1978 PA50 wiring diagram that should be correct.