[gc1066]

Newbie question, assuming I've understood things my UA4C has "Tacho Voltage" shown as selectable via JP6 on the underside of the board using solder pads.

I just can't seem to to find this documented anywhere and the board has come with no solder bridges across the pads.

I'm sticking this in an old skool classic which had a tacho fed via the coil. I assume this means I need to give it a 12v pulse, do I do this by bridging from the middle pad to the 12v pad on JP6?

Appreciate any guidance.

[PSIG]

I just can't seem to to find this documented anywhere and the board has come with no solder bridges across the pads.

Take a look at the schematics for your board at:
https://github.com/turboedge/speedyboards
You'll find the tach circuit and pad numbers to make your solder bridge or solder a tiny wire across. Just to answer your question, here's the circuit:

UA4C_tach-out.png (28.69 KiB) Viewed 242 times

I'm sticking this in an old skool classic which had a tacho fed via the coil.

It will still work that way.

I assume this means I need to give it a 12v pulse, do I do this by bridging from the middle pad to the 12v pad on JP6?

Yes, but you may find that a plain 12V pulse is not enough. If you test and the tach does not respond, you can add an inductor (relay coil, old injector, etc) inline from TachOut to the tach to make a voltage spike like an ignition coil does. Or, leave the tach connected to your ignition coil.

[gc1066]

Top marks, thanks for your guidance.