Two tachometers installation With Jabiru 3300A

[casimiroj]

Hi all! i am currently installing a D120 with a Jabiru 3300A. The tachometer connection between the transducer and the D120 works perfectly, but now i want to have a secondary external tachometer.

How do i connect the second one? Parallel connection? directly to the two wires of the transducer? (wich are already connected to the Dynon).

Thanks in advance!

 

[jakej]

I'd use the transducer wires to run the 2nd tacho and use one of the alternator output wires as the primary D120 tach - you may need a resistor on this wire (Dynon says it's usually not necessary) if the rpm is erratic or try swapping the wires first if that is the case.

HTH
Jake J

 

[casimiroj]

So you mean, the 12v transducer output of the jabiru only connected to the auxiliary tach, and the alternator wire connected to Dynon RPM left, using a 30k resistor (if necessary). Right?

What if i connect the transducer output directly to the two sensors... Just wondering...

 

[jakej]

1. correct
2. yes, but fused - I find the 100k ohm size gives best rpm stability.

Above is easy to do - that way if one method of rpm stops you still have the other - it's called redundancy

Jake J