Page 55 - The Basics IA by ETron Circuit Labs

pushbutton S1, you put a LO, a negative, on Pin 2. This triggers the timer. It now puts out a HI on Pin 3 for a period of time depending on how you have adjusted the potentiometer. Capacitor C1 can be replaced with larger values in order to get longer periods of time.Procedure:Assemble the circuit and connect a 9-volt battery to the Battery Snap. Press and release pushbutton S1 and observe that the LED is lit for a period of time and then shuts off by itself. This is an adjustable timer circuit. The time that the output pulse is HI at Pin 3 of the 555 Timer IC is controlled by the potentiometer setting.Check Your Work Here 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 Here’s What You’ll Need...R3R2 R1LED 1Cathode (flat side)RESISTORhole 8jhole 17i220 Ohm - (Red, Red, Brown, Gold)hole 18ahole 19b1K $ (Brown, Black, Red, Gold) Anode CathodeLIGHT EMITTING DIODE (LED)hole 18hhole 28i6.8K & (Blue, Gray, Red, Gold) hole 8g hole 7gC1100uFB1S1hole 11eELECTROLYTIC CAPACITORShole 10fIC 1INTEGRATED CIRCUITPOTENTIOMETER R41234holes 19f - 16fWIREShole 17a hole 18bnot usedREDBLACKred = hole 30e black = hole 30ghole 19g hole 18g8 7 6 5 holes19e-16eW1 = 30c & 28h W2 = 19a & 30b W3 = 19h & 30hW4 = 10i & 30j W5 = 7j & 10j W6 = 11d & 17dW7 = 16g & 19dSCAN HERE TO SEE MORE ONLINE53AnodeLAB 27Visit us online at www.ETronCircuit.com for more exciting projectsLab Observations