MCI5B tach signal??

[Reddog]

Good Morning,
  So, as I continue to fiddle, the aftermarket Sun tach on the new to me bus does not work. I assume that this is basically a voltmeter driven off of some aspect of the alt/generator? (That's how it works on my backhoe). Where does the signal wire originate so I can start to diagnose the problem and what type/values of the signal should I be seeing? Thanks, Dough at 8000'

[Lin]

If it runs off the alternator, it will be connected to the R terminal.  You might want to contact the manufacturer and find out what type of signal your tach is designed for if you do not know.  They are not all the same.

[RTS/Daytona]

The "r" terminal output is an Inverted sine wave pulse -

Most 6V92 / 8V92-->(2.94 (53/18) gears & 6 pulses per rev=17.66 pulses/rev)
Most 24 volt - 8v71->(2.75 (55/20) gears & 6 pulses per rev=16.5  pulses/rev)
Most 12 volt - 8V71>(2.29 (55/24) gears & 6 pulses per rev=13.75 pulses/rev)

Pete RTS/Daytona