Practical Electronics

Labs

lab #	TOPICS	lab exercises
1	Course Introduction	How to connect the power supply How to read a voltage, resistance, and current with the DMM Reading resistors How protoboard is laid out Each team builds a voltage divider with nom. 3.3 V output, and measure Vout. However, each team works in different resistance regimes (from 100’s of Ohms to 100 kOhm) Each team puts same set of load resistors on their dividers (100’s ohms to MOhm) All teams exchange data and plot results from all teams on one graph in their notebooks - discuss loading of dividers!
2	Resistors and Diodes	LED lamp driver Driving multiple LEDs in parallel and series Use potentiometer to limit current and map I-V curve, each team with different color LED (one team with silicon signal diode) All teams exchange data and plot results from all teams on one graph in their notebooks Build and test 7805 circuit w/load
3	Bridge Circuits	Build bridge rectifier with LEDs and use the load resister to limit current See conduction paths light up depending on polarity of AC input Measure voltage drop across load for both polarities Measure voltage at each end of load w.r.t. ground of 9V battery for both polarities Mechanical switch limits speed, so introduce function generator Find maximum frequency that gives no flicker Introduce Oscilloscope to view waveforms
4	Oscilloscopes and Capacitors	Review operation of Oscilloscope Add ripple reduction filter on bridge rectifier from last week
5	Filters	Each team uses unique RC combination for low-pass filter, measures amplitude response at 10-12 frequency All teams exchange data and plot results from all teams on one graph in their notebooks - discuss different turn-on voltages Repeat 3) and 4) for high-pass filters
6	Relays and Transistors	Drive motor off of power supply Build relay driver to toggle LED Build relay driver to toggle motor Build NPN transistor switch driving LED and demonstrate Drive transistor-controlled LED with function generator Build and demonstrate NPN transistor switch driving motor
7	Op-Amps	Build x2 gain inverting op-amp with potentiometer-based voltage divider as input. Drive a range of loads, compare results to bare divider Give each team a different op-amp circuit to build, measure, and analyze Each team presents results and analysis for its circuit to rest of class
8	555 Timer Circuit	Build 555 as one-shot driving an LED Present internal model and analyze Build 555 as oscillator driving an LED
9	Sensors	Measure resistance of CdS cells under low and high levels of light Use results to select a fixed resistor, use that resistor and CdS cell to make voltage divider circuit to detect light Use comparator to drive LED Voltage divider (potentiometer) as input to comparator-driven LED CdS cell divider as input Light-activated motor Add RC filter to get transient motor drive when light turns on (or off)