Sound powered phones/Howard Community College/Fall 2011/550 EPC Project 2

Problem Statement

Make a sound powered phone system for the Classroom

Team Members

Summary

After not being able to find the parts on sale that we needed, the focus for this project was shifted to actually building one from scratch. Eventually, while trying to make a system, I found a complete system for sale on Ebay and hopefully we can win it.

Handmade attempt of sound powered system

Story

The first part of this project was to build a working microphone. We tested using speakers as microphones and also looked at PVDF films as contact microphones. The voltage output of the PVDF was very good and much higher than that of the speaker, but there just was not enough power generation to drive a speaker output. After many trials, I stumbled upon a Sears Silverstone sound powered system on Ebay. It is currently still on auction so we do not have it yet. Hopefully we do order it and get it installed in the classroom.

Material List

Materials Bought

Magnet Wire
Small Headphones
Shim Stock (copper)

Recommended Purchase

Sound Powered Phone system, or
Sound Powered Phone Receivers

Software List

No software was involved in this project

Time

On average about 5 hours was spent each week on this project.

Tutorials

How to connect and operate sound powered phone http://www.soundpower.com/spcc/index.html

Next Steps

Buy Sound Powered Phone system
Buy additional units and have multiple stations around the lab area

Subjective Critera

While reading these sections, practicing engineers are building up the following impressions about the document. So the following categories are more subjective:

Repeatablitly

Is there enough detail to repeat the work?

Clarity

Is there enough detail that the questions provoked focus on the next step rather than clearing up fog? Is there enough detail that alternative conclusions can be flirted with? Is there enough transparency that finished and unfinished boundaries can be seen?

Integrity

Proving something doesn't exist or doesn't work usually requires exhaustion. Simply saying "it can not be done" is like challenging a pro basketball player (engineer) to one-on-one basketball (find a solution). It does not inspire respect. All the different ways respect is created can be found throughout the wikibook General Engineering Introduction.