Amplifier Project

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Amplifier Project
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Mix up with the soldering boards due to the
bank holiday and the disastrous attempts at the
circuit boards, I have bought some ready made,
but they have been delayed due to bank holiday
Monday. Sorry! Today 1) Situation write
out the situation, and draw a nice picture. 2)
Design Brief 3) Research Questionnaire Ask
Questionnaire Results 4) Specification
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Situation
Electric guitars have solid bodies. If you pluck
a string on an electric guitar that is not
plugged in, the sound is barely audible, there is
nothing to amplify the strings vibrations. To
produce sound, an electric guitar senses the
vibrations of the strings electronically and
sends that electronic signal to an amplifier and
speaker. When playing the guitar it is
important to hear the sounds generated. For this
the guitar needs to be plugged into some form of
amplification device. Traditional amplifiers tend
not to be portable and those that are, still
require some form of power supply. There is a
clear need for a small personal guitar amplifier
that can be easily transported with the guitar,
that allows the guitar to be practiced.
Sony introduced the first portable cassette
player in the late 1970s. Its founder Akio Morita
regularly traveled by plane and he wanted to
listen to music. He asked his engineers to adapt
a small journalist tape recorder to play back
through headphones. He liked the design and the
Walkman was born. Technology has since moved
on, and the Ipod and other Mp3 players mean you
can store over 10,000 tracks on one device.
However, there is still no way that music can be
shared so that friends can listen as well. There
is a clear need for a product that will enable
the output from these devices to be played so
that others can share the music.
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Design Brief
Using the situations that you have just decided
upon, come up with a design brief that you are to
follow for your chosen area. The design brief is
a short description that clearly states the
aim of the design project and in a few words
states the kind of product that is needed. For
example, Design a case is not very helpful to a
designer. Design a case to hold a small
amplifier circuit gives the designer a clearer
focus without applying restrictions
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Research
You are to come up with 6 questions concerning
your amplifier project. Write the questions down
on the sheets provided and ask 10 people to
complete it. By using a questionnaire you are
immediately discovering what the mass public
want. Think about questions such as How big would
you want it? Specify sizes for them to choose
from, DONT leave it open ended. Give 3 or 4
options Would you want the speaker protected or
uncovered? A simple tick box question. Be Simple
and ask What colour you would prefer the case to
be? and give several options.
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Research
Using the data collected from your questionnaire,
you must now put 3 of the questions into visible
data. This means it must go in the form of a
chart. YOU WILL HAVE DONE THIS IN MATHS. Bar
chart -
Put an explanation next to each chart to explain
what they are showing and how this will help you
in your designing
Pie Chart -
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Specification
Once you have a clear understanding of the
problem, you can work out the specification for
your Amplifier. A specification is a list of
things that the final design must do. A good
specification will list the important features in
order of importance. Specifications are an
important part of designing because they provide
a check list against which you can review your
ideas as you are working. They also give you
something against which to evaluate your ideas
and your finished product. For example, needs
to hold a battery does not give the designer
enough information. The case needs to hold a PP3
battery and have easy access so that the battery
can be changed is a clear statement without
restricting the designer.
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Ideas
Once you have written your specification, you are
to complete a series of initial ideas for your
casing. You need to consider things that are out
of the ordinary, BUT are achievable. For instance
if you are doing the portable speaker for the
Ipod, you may want to add an area for you to
place your ipod. You may want the lead from the
stereo jack to be constantly fixed so that the
Ipod slots onto it, You may have different ideas
on how to house the speaker. Make sure that the
four ideas on paper are detailed, coloured, neat,
drawn with a ruler where necessary, and have
notes around them. When it says notes this means
a running commentary on your work.
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Ideas Development
Measure all the separate components that are
going to make up your Audio Amplifier e.g.
speaker, circuit board, battery, etc. Work out
the optimum space needed to contain the
circuit. Use a series of sketches to show how
the sections of your Audio Amplifier are to be
held in your case design. Draw a series of
initial ideas for a vacuum formed case to hold
the Audio Amplifier circuit. Think carefully
about the following a. How the circuit is to be
held in the case. b. How much space is required
to house the circuit. c. How to gain access to
change the battery. Present your ideas as a
series of sketches, highlighting those you feel
are the most interesting with colour.
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Final Idea