Assessment Task 2 Lie Detector

Instructions

·  Obtain the relevant data sheets for the given components

·  Design the circuit on PCB Express

·  Check your completed design against the schematic

·  Manufacture the circuit

·  Test the circuit with the trainer demonstrator using approved test equipment

·  Complete the tasks in this booklet

Component List:

·  9 Volt Battery and Battery Holder

·  1 x 10k Variable Resistor

·  1 x 10k Potentiometer

·  1 x 470k Variable Resistor

·  1 x Buzzer

·  1x 100 uF Electrolytic Capacitor

·  1 X 4.7 uF Electrolytic Capacitor

·  1 x 100 nF Ceramic Capacitor

·  1 x LM358 Op Amp

·  1 x LM311 Comparator

·  1 x LED

·  1 x 470 Ohm Resistor

·  1 x 1kOhm Resistor

·  1 x LDR

·  1 x Superbright LED and small limiting resistor

·  1 x Switch

Task 1

Draw or print an attach the pinout diagrams for the components listed in the box below

Pin-out LM358 / Pin-out LM311

Signed Lecturer …………………………………………….

Date ……………………………………………

Task 2

Print off a plan of your circuit include as a part of this document

Signed Lecturer …………………………………………….

Date …………………………………………

Task 3

Tick off each of the components used in this circuit against the items on the following list. I have completed one for you

Item / Item
Fixed Resistors / Analogue/Digital IC’s
Variable Resistors / Surface Mount Packages
Potentiometers / Rectifiers
Sensing Resistors (LDR etc) / Switches
Fixed Capacitors / Mini Transformers
Electrolytic Capacitors / Decoders
Diodes / Regulators
Zener Diodes / Encoders or Resolvers
Light Emitting Diodes
(LED) / Inverters or Servo Controllers
Transistors / Edge Connectors
Thyristors / Wiring/pins/tags/wire links
Fixing Spacers / Small Heat Sinks
Insulators / Cables
Cable Connectors / Opto-Electronic Components
Protection Devices

Signed Lecturer …………………………………………….

Date ……………………………………………

Task 4

Assemble the circuit and tick off the tools used to make this circuit from the following list

Item / Item
Heat shunts/tweezers / Component forming devices
Snipe nosed pliers / Wire Strippers
Sleeving pliers / Side or end cutters
Bolt fasteners (spanners) / Specialized assembly equip
Anti-static mats or straps
Briefly describe the procedure and tools you used to make this circuit using the box below

Signed Lecturer …………………………………………….

Date ……………………………………………

Task 5

From the following list tick off which functions you think this circuit fulfils.

Circuit / Function / Circuit / Function
Audio amplifier / Filter
Signal converter / Microprocessor application
Signal generator / Comparator
Counter/Timer / Power amplifier
Oscillator / Motor control
Regulated power supply / Sensor/actuator circuit
Logic function controls / ADC/DAC hybrid circuit
Display Circuit / Alarm/protection circuit

Use a schematic of the circuit to highlight (circle) which components function as the circuits you have ticked off on the list above. Staple the completed schematic to this page.

Signed Lecturer …………………………………………….

Date ……………………………………………

Task 6

Test / Equipment / Result
A simulation showing circuit function prior to build / Multisim
Test the continuity between power and ground pins / Multimeter
Test the continuity of the power line to each of the chips / Multimeter
Test the continuity of the earth line / Multimeter
Test the output voltage of the LM358 amplifier when you are detecting a pulse / Oscilloscope
Test the output of the comparator when you are detecting a pulse / Oscilloscope
Adjust the threshold voltage for the LM311 comparator as required to make the circuit function / Multimeter
Adjust the gain of the LM358 amplifier as required to make the circuit function / Oscilloscope

Signed Lecturer …………………………………………….

Date ……………………………………………

Task 7

Use the box below to briefly evaluate this exercise, stating the things you have learned whilst building the circuit, how you overcame any problems you encountered and what if anything you would do differently next time.

Evaluation

Signed Lecturer …………………………………………….

Date ……………………………………………

Practical Observation

Task
The student carried out the following tasks: / Competent
Yes / No
Designed the circuit using PCB Express
Correctly identified the correct components to manufacture the circuit using the schematic and data sheets/charts
Was able to follow the circuit plan and successfully populate the board
Correctly identified polarity dependant components
Demonstrated a safe procedure for manufacturing PCB’s using the correct PPE
Safely soldered the components to the PCB and carried out a visual check of the soldering
Carried out a visual check on all components for signs of damage, carried out a ‘pull test’ on components to check for faulty soldering
Adhered to safety regulations at all times when manufacturing the continuity testing circuit, including the use of correct PPE
Connected test equipment to the circuit in a safe and approved manner
Demonstrated the use of test equipment to test circuit function and trace circuit faults in a safe manner
Left the workspace in a safe and tidy condition when work was completed
Assessor Feedback

Signed Lecturer …………………………………………….

Date ……………………………………………

Student Declaration

All of the work included as a part of this exercise is my own:

Task 1: Signed Student……………………………………….

Date……………………………………………

Task 2: Signed Student……………………………………….

Date……………………………………………

Task 3: Signed Student……………………………………….

Date……………………………………………

Task 4: Signed Student……………………………………….

Date……………………………………………

Task 5: Signed Student……………………………………….

Date……………………………………………

Task 6: Signed Student……………………………………….

Date……………………………………………

Task 7: Signed Student……………………………………….

Date……………………………………………

All tasks complete

Signed Lecturer …………………………………………….

Date ……………………………………………