I've been trying to cascade BJT amplifier to get a gain of 800. My input is 10 mV, and I want an output of 8 V. My question is, how does the gain of common emitter amplifiers work? I've created a BJT that gives a gain (Av) of 7, so the output is 70 mV. When I cascaded it to another emitter amplifier that was built the EXACT same as the previous, the output it gave was 2 V, meaning a gain of 200. I couldn't find any calculations or logical reasons why it does this. If anyone knows of a formula or something that explains this it would be much appreciated! Even a short explanation will do. This is my circuit. The first stage is the buffer stage with a gain of around 0.8. It thus gives a 10*0.8 = 8 mV peak-to-peak output.
Adding the common emitter amplifier stage, the output is 600 mV peak-to-peak as seen below:
I cannot seem to apply the formula below to get even close to similar results for the output at the second stage. This is the formula I've learned and tried to apply but it doesn't work for me or explain the 8 mV to 600 mV gain.