I have this same tach. It arrived today. It's a really nice looking unit. But I will need to build a driver circuit to give the sort of signal it needs.
I haven't found specs for it yet, so if anyone knows what it is looking for, I can make a circuit that works.
I will have 12V system available. I'm guessing it just needs a 12V pulse like one could get off the primary coil of an automotive system, right?
So if I set up a circuit that switches 12V to it every time the blue wire goes above a positive threshold, that would probably work, no?
EDIT: So I watched the video above, and they throw up a schematic at the end of it that is what I was envisioning:
Most any NPN small signal transistor should work.
I'm planning on adding a lower voltage coil to my magneto to derive my 5V and 12V systems, so I'll probably drive the tach from that coil rather than the blue CDI wire.
If anyone has built similar for their CG yet, let me know.
A 12V source is necessary in general for this tach, so I'd love to see other people's solutions too.
EDIT #2:
Since I ultimately plan to have an arduino or raspi on board to collect engine data, if I use a version of this circuit to drive the tach, I'd also add a 5V switching output as well for the input to the micro. I'll share when I get it going.
A bigger challenge for me is to make an attractive mount for the tach. I have a 10mm mirror mount clamp that will probably work...
I haven't found specs for it yet, so if anyone knows what it is looking for, I can make a circuit that works.
I will have 12V system available. I'm guessing it just needs a 12V pulse like one could get off the primary coil of an automotive system, right?
So if I set up a circuit that switches 12V to it every time the blue wire goes above a positive threshold, that would probably work, no?
EDIT: So I watched the video above, and they throw up a schematic at the end of it that is what I was envisioning:
Most any NPN small signal transistor should work.
I'm planning on adding a lower voltage coil to my magneto to derive my 5V and 12V systems, so I'll probably drive the tach from that coil rather than the blue CDI wire.
If anyone has built similar for their CG yet, let me know.
A 12V source is necessary in general for this tach, so I'd love to see other people's solutions too.
EDIT #2:
Since I ultimately plan to have an arduino or raspi on board to collect engine data, if I use a version of this circuit to drive the tach, I'd also add a 5V switching output as well for the input to the micro. I'll share when I get it going.
A bigger challenge for me is to make an attractive mount for the tach. I have a 10mm mirror mount clamp that will probably work...
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