Engineering 44 initials (Kuo-Hao) Jeff Liao: Day 07 03/17/2015 Time-varying Signals and extra (A BJT Curve Tracer)

Lab: Time-varying Signals

This lab is mainly focus on using waveform generator to general the wave vs. time oscilloscope.

Graph of circuit

Graph of Vin and Vout .Top: Vin Bottom Vout

On this pre-lab we understand with resistor R1 = R2, the Vin pass R1 will appear to be the top graph of second graph with amplitude = A, and since Vout will require current to pass R1 and R2, the resistor for Vout is 2R because R1 = R2. With twice larger resistance the voltage will decrease by half and it lead up to the bottom of second graph with only half of amplitude which is A/2.

Lab Procedures:

V1in Graph

We first set up the figure 1 which is a sinusoidal voltage with amplitude 2V and frequency 2kHz.

V1out Graph

The Vout amplitude is 1V and its frequency is same as 2kHz.

The Vout amplitude is 1/2 of Vin as what I expect from pre-lab.

V2in

Same for the first one we set out figure 2 with triangular wave with amplitude 2V and frequency 2kHz

V2out

The Vout amplitude is 1V and frequency is 2kHz which Vout amplitude is 1/2 of Vin as what I expected to see.

V3in

Last is the square wave which I also put in 2V for amplitude and 2kHz frequency

V3out

The Vout has also provide 1/2 amplitude of Vin which is 1V and still keep the same frequency of 2kHz

A BJT Curve Tracer:

This lab is mainly for use to understand the transistors

On this circuit setup we can see transistor has separate to 3 different path one for Ic to flow in one is connect to ground and one for Ib to flow in.