I'm having to design a BJT single stage amp for my electronics II class and can't get it even started.
The supply is suppose to be 14V
and the signal is 200mVp-p with rs=1.5k
The ouput is to be 6 Vp-p across a 47k ohm load
The lower cutoff freq has to be less than 35Hz while the upper cutoff freq must be between 50kHz and 200kHz
I have to use a 2N2222 trasistor: hfe=75

Anyone have any suggestions on how to go about getting this done?
Thanks in advance.

 

First, think what bias you want to apply to the transistor and then calculate your Q-point to be in the middle of the supply voltage as to have the maximum excursion of the amplified signal. Then calculate the input capacitor reactance to be ten times less than the thevenin equivalent resistance on the base of the transistor at 35 Hz. This is to ensure that signals with frequencies above 35 Hz are amplified with almost no losses. If you will use a common emitter amplifier then calculate the bypass emitter capacitor a proper value as not too lose gain at frequencies as low as 35Hz. Also, calculate the output capacitor with the same thinking as the input capacitor. For the upper cutoff frequency consider how the gain of the transistor changes with frequency.

 

I will be using common emitter biasing

 

Sketch out your schematic and post it. You can label the componets without their values.

Then everyone would be on the same page as you work your way to the solution.

 

The circuit will be set up as above

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http://s291.photobucket.com/albums/ll282/cwilli85/?action=view&current=circuit-1.jpg

 

Your circuit over at PhotoBucket (it should have been posted here) will work fine if you calculate the value of its parts correctly. Use simple arithmatic.
Use Ohm's Law and the formula for a coupling capacitor, 1/(2 pi RC).

 

I can't get the freq right

 

None of the values i plug in work out right

 

The calculation for a coupling capacitor's value is simple arithmatic. It is 1/(2 pi RC) which is 0.16 times RC. Then the response is down 3dB (half power or 0.707 voltage).