Post by
Wulfgang »
https://forums.nicoclub.com/wulfgang-u10889.html
Thu Apr 15, 2004 7:37 pm
Does it involve an AVR or PIC? I had one designed, but after measuring and finding out that the signal to the tach is just variable duty cycle (the inverted dwell signal), I decided that tachs are waaay to easy to make and that using the pot on the back of the tach or a very, very simple 2/3 voltage divider had to work at least as well as any MCU solution. Heck, Nissan even helps out by increasing the dwell when the battery voltage is low so you don't have to compensate for voltage variations. Just buffer and lowpass the inverted dwell signal at about 10 Hz and put it through an ammeter.