Wanted: Information on the Motorola MC3484 series FI driver

[Ben Wong]

Hi,

>I'm jumping in the middle of this (haven't tracked this specific 
>conversation), but if you are trying to read RPM from coil signals on a 
>two coil system, another way is to use two diodes to connect the two 
>signals together.  If you put the diodes in right, the resulting signal 
>is the combination of the signals to each coil and the output should be 
>your desired signal.  
>
>Best Regards, Mazda
>
>
Just wondering..does this theory applies to a vehicle that has individual
coil for each spark plug? I'm trying to hook up a dash mounted tacho but my
current wiring is only going to one coil and this gives an erratic reading!
By the way it is a Nissan 200SX (Turbo)- CA18DET ECCS engine.

Thanks everyone.