Lab 4 - Transistor Switching

Transistor Switching

Objective:

To understand the schematic of a transistor and its functioning components

Process:

Set up breadboard with 3 resistors, transistor, led, and switch to test behavior of transistor with a finger tap using circuit given.
Elements will be S1: Pushbutton
                         R1: 180 ohms
                         R2: 10k ohms
                         R3: 680 ohms
                         Q1: 2N3904 - transistor
                         D1: Led

Circuit schematic for Finger Switching

Circuit Complete for Finger Switching.

To demonstrate the relationship between the current going through the base and the current emerging from the emitter a new circuit will be built with a potentiometer and two ammeters to showcase both currents.
Elements will be R1:180 ohms
                         R2: 10 ohms
                         R3: 180 ohms
                         P1: 1M linear potentiometer
                         Q1: 2N3904 - transistor

Circuit Schematic for Current Testing

Circuit Complete for Current Testing

Data Collected for A1=I_b and A2=I_e

Data Analyzed in A1 vs A2

Data Calculated - Beta found

Conclusion:

During the first part of the experiment we found just how sensible a transistor can be by touching it and distinguishing the amplified voltage and noticed how bright or dim the led turned. As the experiment progressed  the components that make up  a transistor are the collector, base, and emitter. The transistor essentially amplifies any changes in current applied to the base creating a ratio from incoming current to outgoing. This ratio is called the beta gain and in our experiment yielded the value of 5.93. Unfortunately, range values were not hugh enough to establish a saturation point of when the internal resistance can not go any lower.