Sorry but I thought I would follow the one question per post rule (so reposting with focused question):
How do I get signal amplification with a multistage common source amplifier with active load ?
I have a working version of a common source amplifier with an active
load (a drain current of 50 uA) going into the drain (here : https://docs.google.com/open?id=0BwG45lg3wcwnU3ZDQ3NtNjZCM2s the file is titled: Project_Working with 1000 Gain-Nov-30-2012.zip is a file that has the
original circuit which gives an input signal of 1mv an amplification of
1000 (to around 1V).)
All I did was add another stage to
this amplifier as listed in countless examples of multi stage common
source amplifiers throughout every book (and online like here : http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-012-microelectronic-devices-and-circuits-fall-2005/lecture-notes/lecture21annotat.pdf ). The second stage
has the exact same specs as the first stage so I should get multiplication of gain or double the gain right ?
Apparently I don't because instead I see an attenuation of signal (here
is this new project: https://docs.google.com/open?id=0BwG45lg3wcwnNWRXUlV6RVdkNU0 ) Why is this attenuation happening or rather how do I get the predicted gain of stage 1 gain x stage 2 gain ?
Well, N2 has a Vgs of 12V, that going to be pretty certainly saturated and not allow much action at the drain.
Also, if you did get this "anything like" working, 1mV * 1000 * 1000 is going to be greater than your 12V supply so something is going to have to give!