I attached a picture of how to set up a voltage divider. Use Rb of 10K ohms and Ra of 1K ohm for division by 10. This should make your generator signal 12.5 mV. But use Rb 100k and Ra 1k for adjustability. This divider is standard lab practice. (On edit: Oops I forgot the line between the base and the node at R1 and R2. It's the same as your circuit.)

As pointed out by everyone above, you need a small signal at the input to avoid the type of distortion you've been getting. I'll tell you more about this if you want. For now just make that divider and you should get rid of your distortion. Be sure not to turn the overall input voltage up past 10 mV. This means your output voltage will be smaller than you've been looking at, but at least it won't be distorted.

 

@hobbyist: I appreciate your help and I realize that had I stated from the beginning that there should be a bandwidth in which the transistor would work (although no specific bandwidth was imposed to us), maybe you would've told me straight out that it wasn't possible with that large of an input signal. At this point I don't think you could come up with a design that shows no distortion in the medium frecuencies (i.e. the capacitors are seen as short circuits by the AC signal) with a ~120 mV p-p input signal. Feel free to prove me wrong if it can be realized.

Hi,

From the way your explaining things now, I can see that your more advanced in this, then I am, I could learn from you, about designing for freq. response.

Keep up the good work, your learning this stuff real well.

This thread makes me want to get out my books, and learn how to design for freq. response.

I always seemed to skim over the literature that dealt with coupling networks, freq. analysis, because I seemed to have gotten the notion, from what I read all the time, that the coupling capacitors, just needs to be large enough to handle the lowest freqencies.

But this thread has me wanting to take the time and read my course material, dealing with coupling capacitors, and bypass capacitors.

So I learned a lot from this too.

have a great day..

 

The transistor has severe distortion because it has no negative feedback. The bypassed emitter resistor causes the gain to be as high as is possible which is hardly ever needed for a transistor.
If you simply reduce the input level then the distortion will be a little less but there will still be distortion. But if you add negative feedback to reduce the distortion and reduce the gain then it will be much better.
Now the distortion is so high that you cannot even measure the gain because the positive-going part of the output waveform (for an NPN transistor) is compressed.

The low frequency response is simply determined by the value of the coupling capacitors and the load resistance that they drive. The high frequency response is very high with modern silicon transistors (and was very poor in old germanium transistors). Negative feedback also increases high frequency response.