rev counter

Hi there, newbie here in the uk. thanks for letting me join.
I have a 1982 spectre 1100 which is a dream to ride however my rev counter does not work. the turn light etc do work but not the rev counter itself.. have  any of you guys had the same issues, will add that I also have a charging issue. here's in hope.. safe riding guys 

Welcome from Leicestershire Will, the tacho senses from one of the coil trigger wires so check the pulse into the rev counter with an LED test light (best when cranking as with the engine running may be hard to see the LED pulsing)
What is the charging issue ?