I built circuit shown bellow (NPN BJT):
Everything worked normal as it should (except of unwanted distortion). There is that one strange thing I'm seeing lately when I connect oscilloscope's probe between emitter and ground. It is the amplitude of the signal measured - when the amplitude of F.G. is some mV, the emitter amplitude more or less follows the input amplitude measured between base and ground; things change when the input voltage is increased for few 10mV, where the emitter's amplitude looks like this:
Eventually proceeding to more sharp shape of peak.
Even stranger thing is that, after those triangular waves are shaped, the voltage simply stops at this point as the input voltage is increased.
Does this behavior has to do anything with almost constant Vbe which is approx. 0.7V?
Or is this another unwanted distortion produced by transistor?