Transistor circuit

[enjoyliffee]

Please help me analyse this circuit. My question is this: Why does the LED NOT glow when the base terminal is disconnected ?

[I_Daniel]

There must be something wrong. I am logged in but see no circuit that you refer to. Your post also does not indicate that there is an attachment !

[bcct]

I forgot about the current...
When the transistor is on (i.e. the input signal is logic 1) the current will pass from the +Vs to ground, in other words from the collector toward the emitter.
But when the transistor in off (i.e. the input signal is logic 0) no current will flow through the transistor because it's OFF.
If the output signal is applied to a load (e.g. Resistor RL) the current will flow from +Vs through Rc and then through the load RL to the ground.