I am analyzing work of amplitude limiter built on transistor, and I can see an incoherence as far as rising times for different frequencies and input voltages are concerned. The problem is: the bigger voltage on input for 1kHz is used, the longer rise time is, but the bigger voltage on input for 30kHz is used, the shorter rise time is. Are my measurements wrong?
I know that theoretically rising time for square wave equals 0, but what is the relation between rise time, frequency and input voltage?
Here are the oscilloscope output photos:
1: 1kHz 2V
2: 1kHz 5V
3: 30kHz 2V
4: 30kHz 5V