Help with CD box and tachometer XJ6 S!
 

This is a new request for help with a tachometer that is jerky and erratic. I was just about to take the tach over to the instrument repair shop when it was suggested that I make some changes to the wiring between the tach wiring and the CD box. Has anyone had this problem ? Has anyone cured the problem by adding a 100 ohm resistor to the tach to + on the coil?