Day 6 (BJT Curve Tracer lab) bjt incomplete

If nobody mentioned that there was a dirty version of the BBROYGBVGW memorization for resistors then I would definitely have learned a clean version. Unfortunately every time I want to read a resistor I have to go through bad boys doing UNSPEAKABLE things to young girls but Violet is unaffected by that. Anyway the class started by having students read resistor values for a set of unknown resistors.

We then learned about super meshes, which are branches that encompass current sources. We analyzed this circuit using that technique and found that the arbitrary currents had a value of -1.33, -3.07, and -.067 amps.

The lab that followed was an experimental test to prove that mesh analysis is a technique that gives a true assessment of a circuit. The pre-lab starts by calculating the theoretical value of a current and voltage drop at two specific points. The current going through the 10 kiloohm resistor is- .322 miliamps and the voltage drop on the 6.8 kiloohm resistor is five volts.

The circuit was built and the voltage measured was 4.97 volts and the current measured was -.34 miliamps. The percent error respectively was -.69% and 5.59%, which is pushing the limit of what is acceptable since these small circuits don't have a lot of places to introduce sources of error. Here are pictures of the circuit, the results, and the calculations.

Next was the concept of the BJTs and to understand how they worked we analyzed a circuit using mesh analysis. The two currents entering the BJT were 165 microamps and 8250 microamps and the voltage across the BJT was 5.175 volts. 

Last was the lab A BJT Curve Tracer, which was a nightmare to set up if you had the newest version of diligent. We used an older version and found that the beta of the BJT was about 37.5 and the base early voltage was around 1.5.