I thought I would ask on here as you guys seem to know everything, I'm looking for a strip type tacho, one with multiple leds , 1 lights up at 1000rpm 2at 2000rpm etc. It needs to be pretty small as it's going in a mk1 mini that I want to keep standard looking as possible
Google "LM2917N tacho" might point to something.
I made a more complicated one a few years back using a Microprocessor.
Main bit is to get a clean signal from the ignition.
LM2907N or LM2917N to convert frequency to voltage and LM3914 to convert voltage to a 10 segment LED bargraph?
Incidentally, IIRC, LM3914s can be cascaded to produce longer displays.
[Edited on 17/12/19 by SteveWalker]
I used to have just what you're describing, i think it was 8 or 10 LEDs, only about 8mm deep and in a flexible rubber case so you could apply it
on a curve or in a groove, etc, and i thought it was made by SPA, so but i can't find one for sale online anywhere....
So the nearest i could find was this one
Julian Ilett tried building something very similar.
this is his third iteration...