For assessment 2.1:
• Practical utilisation of media technology: Ability to describe and measure parameters of waveforms; analyse time and frequency domain signals using mathematical tools, select and
use appropriate techniques for image capture, process and display.
For assessment 2.2
• Demonstrate an understanding of digital media applied to audio and visual signals, including conversion between analogue and digital formats; the fundamentals of data storage and
transfer
• Present original analysis of technologies and markets from wide ranging research.
Assessment Details:
Assessment 2.1
You are required to produce a report detailing how you would construct and test an electronic circuit. This does not involve you actually carrying out the laboratory experiment yourself.
(1)
You need to detail a circuit comprising a resistor (R) of 1 kilohm (1KO) and a capacitor (C) to produce:
(i) a first-order low pass filter with a cut-off frequency of 2.5KHz
(ii) a first-order high pass filter with a cut-off frequency of 4KHz
You are required to produce a circuit diagram for each case, and calculate the value of the capacitor required to meet the frequency response requirements stated.
(2)
You need to detail a laboratory experiment stating how you would test these two circuits.
You need to include the following sections in your account:
(i) Aim of the experiment – a brief introduction to the experiment.
(ii) Construction of the circuit: How you would construct the circuit suitable for this experiment: this may involve (a) a prototype board (soldered or plug-in type) using discrete resistor and
capacitor components, or (b) a resistor box (i.e. the type with adjustable dials to select the required value) and a similar capacitor box.
(iii) Equipment used for the experiment. This may involve a signal generator, an oscilloscope, suitable connecting wires and any other suitable laboratory equipment you would need.
(iv) Method/Process including Diagrams: How you would conduct the experiment. State any specific measures you need to take to ensure the experiment is carried out correctly and to obtain
accurate results. Produce diagrams as necessary to show the set up of the experiment.
(v) Measurements: state all measurements you need to take to derive the filters’ characteristics from 20Hz to 10kHz. Produce a table that you would need to fill in for the experiment, e.g.
frequencies measured, signal levels, etc.
(vi) Calculations: Since the frequency response is given as decibels (dB) you need to convert the signal input / output levels in to dBs.
(note – Gain, dB = 20log Vout / Vin )
(vii) Conclusions and Discussion: State any issues which need special attention. Discuss any conditions, or factors that may influence the accuracy of results that may be obtained.
Layout of Technical Reports
It is important that a media technologist is a good communicator. He or she must be capable of transmitting information by the written word.
The assignment is intended to fulfil the following functions:-
• To reinforce your knowledge of the subject matter by repeated application of the underlying principles.
• To give you the opportunity to develop a logical and methodical approach to the solution of problem.
• To use the same skills in the presentation of technical information.
Therefore when you complete the assignment, treat it as a vehicle for demonstrating it as your understanding of the subject.
Practical assignment involves the use of equipment and measuring instruments in order that you may discover certain technical facts or to verify the theory. This form of exercise will need to be
properly documented so that, if necessary, another person can repeat your procedures to confirm your findings or not as the case maybe. In these cases a more formalised form of written
technical report is required, and the following format is generally acceptable:
‘Title’
Aim: This needs to be concise and a clear statement as to what it is you are trying to achieve.
Objective: This needs to be concise and a clear statement as to how you will achieve your aim.
Apparatus: This will be a list of equipment and instruments used, quoting serial
numbers where appropriate.
Diagram(s): Diagrams should be clearly labelled.
Method: This consists of a series of numbered paragraphs that describe each set of the procedure carried out. This section of the report (as with the rest)should be impersonal and in past tense.
Words such as ‘I’, ‘we’, ‘they’,‘us’ should not be used. Thus, instead of writing a phase such as ‘We setthe voltage to 0V and I adjusted it in 0.1V steps….’ you should write ‘The voltage was set to
0V and then adjusted in 0.1V steps….’
Results: All measurements and setting should be neatly tabulated. To avoid writingunit symbols along side figures in the body of the table the appropriate units need to be stated at the top of
each column. If there is more than one table of results then each one should be clearly identified. These points are Illustrated in Table 1 below:
Table 1
pd (V) I (mA) R (kO)
0.0 0.00 —–
1.0 1.25 0.80
2.0 1.75 1.14
3.0 2.20 1.37
4.0 2.75 1.46
Etc
Analysis: This should compare your practical results with theoretical analysis. This may include:
Calculations: This section may not always be required, but if you have carried out any calculations using measured data these should be shown here.
Graphs: In most cases the tabulated results form the basis for a graph (or graphs)which must be carefully plotted on appropriate graph paper. Simple lined or squared paper is NOT adequate.
Try to use as much of the paper as possible, but at the same time choose sensible scales. For example let the graduations on the graph paper represent increments such as 0.1, 0.2, 0.5, 10 000,
etc. By doing this you will make it much simpler to plot the graph in the first place, and more importantly, very much easier to take readings from it subsequently.
Conclusions:Having gone through the above procedure you need to complete assignment by drawing some conclusions based on the all the data gathered. Any such conclusions based on all the
data gathered. Any such conclusions must be justified. For example, you may have taken second variable x. If the plotted graph happens to be a straight line that passes through the origin then
your conclusion would be as follows:
‘Since the graph of y versus x is a straight line passing through the origin then it can be concluded that y is directly proportional to x’. Finish with a sentence to state if the original aim was met.
Discussion:Discuss your experiment and its results and conclusion in relation to existing knowledge and theory on the subject, including how the technology is utilised in audio-visual
applications.