Page 25 - The Basics IA by ETron Circuit Labs

Here’s What You’ll Need...R1R2Q1eRESISTORhole 14ahole 23a220 Ohm - (Red, Red, Brown, Gold)hole 12dhole 23d3.3K % (Orange, Orange, Red, Gold) c bNPN 2N3904Collector hole 3cBase Emitter hole 4c hole 5cNPN TRANSISTORPUSHBUTTONhole 10e S1 hole 12eAnode CathodeLIGHT EMITTING DIODE (LED) a b c d e 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 a b c d e f g h i j 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 f g h i j LED 1Cathode (flat side)LED 2Cathode (flat side)hole 6e hole 4ehole 14c hole 13cREDB1WIRESW1 = 20j & 5e W2 = 10d & 6cW3 = 13a & 3aBLACKSCAN HERE TO SEE MORE ONLINEred = hole 23e black = hole 20f23LAB 12Notice that electrons did not flow until the switch was pressed. There must be Emitter-Base current before any current will flow in the Emitter-Collector circuit. This act of a smaller current controlling a larger current is referred to as amplification.Within limits, as you increase the current in the Emitter-Base circuit, it will increase the current flowing in the Emitter-Collector circuit. By adjusting the value of R1 you may use an ammeter to observe the change in currents.Procedure:Assemble the circuit and connect a 9-volt battery to the Battery Snap and press the pushbutton switch to cause the current to flow. Both LEDs should light up. When you release the pushbutton switch, both LEDs should turn off.Observations:By doing this experiment you have seen that LED 2 in the emitter-collector circuit is brighter than LED 1 in the emitter-base circuit and that both LEDs light up only after the pushbutton is pressed.Conclusion:By completing this Lab you can conclude that the NPN Transistor can work as a current amplifier, sending more current through LED 2 than LED 1.Check Your Work HereAnodeAnodeVisit us online at www.ETronCircuit.com for more exciting projectsLab Observations