Please help me with the number (km/h)

naja für irgendwas muss diese zahl ja gut sein die es schafft einem den spaß an einem preiswert über ebay ersteigerten tacho mit dzm zu verderben

look on the picture. under the "km/h" there is the information you need the "W" für Wegstreckendrehzahl and the turns (this is the number you need).

the 4 cm was already on this netpic and doesnt have a meaning for you.

cool
thanx, i had no clue that W=?.. is the number i'm looking for.
I will post some photos with the homemade sensor, very soon.
More photos will come.

Cosmin, I have 2 speed sensors that insert into the gearbox, one with 6 imp and one with 16 imp. If you want one, contact me at 0744.552.750

Yes, I am from Bucharest/ Romania. :))

Some of the pictures i've made. The sensor is made up with parts recovered from an old VCR.

the sensor works good up to 85-90 km/h, i don't know why, but after that it stops working and it shows some random values between 80 and 90km/h, even if the real speed is almost 120km/h.
I've had little time for testing, i hope the problem is in the microcontroller and the software i wrote.
This week i will test it at home, with a DC motor with variable rpm. The drilling machine (as in the pictures) is able to rotate the senson until it reaches about 44Km/h. That's not enough, the problem appears at 80-90km/h.
I have to find a way to make it work somehow