I posted some time ago about a tachometer/spedometer got a few good circuit's to attempt. But it's not really what i am looking for. it was a design for a speedometer that counted rpms of a tire. for a car. for a little bit about what i am looking for.
The application.
is in some R/C toys i have. mainly motors and gear boxes. I'm doing my best at learing gear ratios but i get mixed up with the drive driven fractions. I would like for something fast and simple to glance at.
i would prefer to use a 9 volt battery for a power source.
It would be a 4 digit read out that might peak around 9k rpms.
I recentally purchased a new drill press and it has an rpm indicator like i am describing but i do not want to tear apart my press .... maybe in a few years. any insite to this would be wonderful. all i need it to do is drive a 4 digit leds and tell me how many times a min it's counting.
thanks
The application.
is in some R/C toys i have. mainly motors and gear boxes. I'm doing my best at learing gear ratios but i get mixed up with the drive driven fractions. I would like for something fast and simple to glance at.
i would prefer to use a 9 volt battery for a power source.
It would be a 4 digit read out that might peak around 9k rpms.
I recentally purchased a new drill press and it has an rpm indicator like i am describing but i do not want to tear apart my press .... maybe in a few years. any insite to this would be wonderful. all i need it to do is drive a 4 digit leds and tell me how many times a min it's counting.
thanks