BJT Homework Help: Troubleshooting Results

[go2255]

This is the result from a lab,but I am not sure the results are correct.
Also,when I try to find I(c) , I(b) and I(e),by measured V(RC) and V(RE),I find the results strange.
I guess the combination of R1=10k and R2=10k is under linear region,but the dc gain is so small.
For combination of R1=10k and R2=1k,Idon't know why the I(b) is negative.Is it the cut off mode?
And for combination of R1=1k and R2=10k,it should be in saturation?
I guess R2 is like a battery so current I(b) flow ,but how about R1??

 

[NascentOxygen]

You calculated I_B using I_E - I_C. This can be inaccurate when I_E is close in value to I_C.
There is another way you can determine the value of I_B in each test situation, it's a more accurate method, too.

What is this second method I speak of?