can anybody could help me in design a water level..?
the possible components that i would be using are, transistor, diodes, led, resistor, capacitor... i'm not allowed to used ic....
in a container their are 5 measurements, empty, 1/4, 1/2, 3/4, and full.. in each measurements the led must turn on, but if it is empty the led in other measurements must be off, and it is in 1/4, the led in empty must be off and so on....
Does the transistor have to be a BJT (bipolar junction transistor...a "standard" transistor) or can it be a MOSFET (metal oxide semiconductor field effect transistor)?
If you don't have enough basic electronics knowledge to figure out how these components could be combined to implement a water level [dectection] circuit, you could start by Googling: water level detection circuit
You will find things like this: **broken link removed**
this is my circuit i may.... i need, is to turn on one led according to its level... but the result of it is all the led are turning on... hope you could help me...
Ummm, why not use a float connected to a lever + arm. use the arm to bridge contacts, with contacts stretching from E to 1/4, 1/4 to 1/2, 1/2 to 3/4 and 3/4 to full.