### BERTHOUD High School Amplifier Project

```Matt Duwe CSU Fellow EE
Scott Kindt Physics Teacher
Robb Sommerfeld P.O.E. Teacher
Mil Santos Algebra II Teacher
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Working in project teams, students will
design & build a stereo system that will
amplify the audio signal from an I-Pod.
Project teams will be divided into three
groups.
(a) Amplifier design. Outsource schematic to
Kate’s students.
(b) Power supply & box for electronics.
(c) Speaker & cross-over filter Design.
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Students will learn the basics on:
-Circuits, resistors, capacitors, transistors
-Ohm’s Law, Power equation.
Time Line
http://www.rockymountainstars.com/Amplifier
_Project_CSU_GK12.htm
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The Junior Fellow will be responsible for
integrating all the parts into a working
system.
Does the power supply meet the
requirements for the amplifier?
Do the speakers have the efficiency to match
the amplifier output?
Are we under the \$100 budget?
Solar powered stereo.
Hand crank up stereo.
Vacuum tube amplifier.
Portable battery powered stereo.
Standard solid state amplifier.
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Power in vs. Power out, amplifier efficiency
Maximum output in db
Frequency Response
Harmonic Distortion
Cross-over point for speaker filter
Other measurements
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Robb’s POE class will devote more time to
material science along with the CAD design &
construction of the amplifier box.
Students will have the opportunity
experiment with different materials to build
the stereo & speakers around the Kelvin 20
watt amplifier.
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Define a Problem
Brainstorm
Research and Generate Ideas
Identify Criteria and Specify
Constraints
Explore Possibilities
Select an Approach
Develop a Design Proposal
Make a Model or Prototype
Test and Evaluate the Design using
Specifications
Refine the Design
Create or Make Solution
Communicate Processes and Results
– ITEA Standards for Technological Literacy
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Mil’s Algebra II classes will build the Kelvin 20
watt amplifier however their focus will be on
testing and measuring the electronics.
The Algebra II classes will also test the
custom designed amplifiers made in the
physics classes. The results will be compared
to the Kelvin amplifier kits.
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Application of the Design process.
Working together as an engineering team.
Principle behind amplifiers & circuit design.
Power Supplies, AC-DC conversion, rectifiers.
Hi pass, low pass filters with capacitors & inductors.
How to test electronic equipment, amps & speakers.
Efficiency of amplifiers.
Application s of Algebra II & Engineering.
How to make a scientific poster.
How to present your project & ideas to a general
audience.
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 Microwave frequencies
 Doppler Effect
 Doppler Radar Gun to measure speed
```