Circuit

I to see this circuit in web http://home.cogeco.ca/~rpaisley4/Traffic145.html
good idea circuit.

Basic Circuit Operation

The circuit is stepped through the sequence by an adjustable LM555 astable oscillator.
The Oscillators output is divided by a 74LS90 divider into a 10 step BCD weighted output.
The BCD output then drives two 74LS145 - 1 of 10 [...]

Here is Calibrated Led Circuit. It Use IC LM334 (3-Terminal Adjustable Current Source) For Display Led Current. By current that flow through LED control with the value R.
Such as
R = 10 OHM : I LED =6.4mA
R = 15 OHM : ILED = 4.3mA
In order that you can use Volt supply 3V-20V and [...]

This be Basic Thermometers circuit. When see the circuit will think give the a little equipment just IC LM334 and , Resistor only. Can use formed take the temperature the base by lead output. build suit meter Out put voltage 10 mV/K. For [...]