Electronic rev counter...

[Ian Williams]

In my experience if you can now find a 6 Volt unit yes they work, as noted they pick up through the coil wire. I have used a couple of smiths units but found them to be unreliable in the long run, over several years they start to jump around and read inaccurately or simply pack up altogether. I believe that this is due to the amount of electrical noise on an unregulated A7 system eventually damaging some of the electronic components....Simon or one of our other electronics experts may have a solution. You may be able to use a 12volt unit with a step down transformer, but again I am not sure how reliable it would be in the long term.