Modify and print a telegraph, then connect it to a Makey Makes and Scratch program in order to telegraph coded messages.
Overview and Background
3D Print a Telegraph
In this lesson, you'll read some of the history of the telegraph and how it was shaped by and shaped society and culture. Then you'll modify and print your own telegraph, before learning how to encode and send messages!
Lesson Plan and Activity
1. Background Reading
To begin the unit, I read the children’s book Jack Rabbit McCabe and the Electric Telegraph by Lucy Rozier. We then discuss the themes, myths, assumptions, ideologies, and cultural norms present in the text.
Readings to discuss in class before this activity:
• James Carey, “Technology and Ideology: The Case of the Telegraph”
• N. Katherine Hayles, “Technogenisis in Action: Telegraph Code Books and the Place of the Human,” chapter in How We Think, Digital Media and Contemporary Technogenisis
• Excerpts from Tom Standage’s The Victorian Internet
• Nicole Starosielski, “Gateway: From Cable Colony to Network Operations Center,” chapter in Undersea Network (Sign, Storage, Transmission)
• Tom Veal and Mike Cook, “Less is More” chapter in Twitterbots: Machines that Make Meaning
2. Download STL files for telegraph
3. Modify Telegraph
Use Tinkercad to (optionally, or for extension project) make changes to the telegraph. The lever could provide a good opportunity to make such changes. Students may want to add a name or logo to the lever, or even redesign the part of the lever that the finger pushes down on. One question driving this redesign might center around the question of shape is most comfortable for continued use of the telegraph? Can the current flat circular surface be improved?
The 3D printed parts can be assembled like those in the video found here: https://youtu.be/hFpNdqtW42A. However, we will be using a Makey Makey rather than a battery and light to complete ours.
6. Connect to Makey Makey
In this example, I’ve used conductive paint on the lever, which then contacts with a piece of metal under the lever. This metal is then connected back to the conductive paint and run to the far side of the telegraph so it is out of the way.
At the back of the Makey Makey, I use another piece of metal leading out of the conductive paint, and connect that to the alligator clip from the Makey Makey.
The green wire is the main contact for the telegraph, and I have connected to the up arrow button on the Makey Makey. A second grounding wire will need to be run to a place that you hold the telegraph while using it.
Above, you can see that the right screw is connected using a combination of conductive paint and a small wire to the alligator clip that is connected to Earth on the Makey Makey.
This is a natural spot to hold while pressing down on the key, especially if the device is not screwed or bolted down.
7. Connect to Scratch Program
Students should practice transmitting basic Morse code using this setup.
9. Code messages
After developing confidence in telegraphing skills, students should locate a telegraph code book. An example of one can be found here: https://people.duke.edu/~ng46/collections/abc-universal-code-1881.pdf, but others are also available. Using this code book, they should work in pairs. One student will created a coded message that they will send to the other student. The student should transcribe the telegraph code received, and then use the code book to decode the message. Students will then switch roles.
Assessment: To conclude, I will project a coded, telegraphed message onto the projector. Students must decode it correctly. Additionally, students will craft an out-of-class reflective essay on how the telegraph has impacted society.
3D Printer, Computer, speakers, projection system, Makey Makey, conductive paint and/or wires, rubber band or spring
These outcomes can be used to create a rubric:
• Construct a telegraph system using 3D printed materials and microcontrollers
• Analyze present day media (e.g., Twitter) technologies as selective accumulations of past media, networks, genres, practices, and political-economic arrangements.
• Record and then interpret coded telegraph messages
• Appraise the role the communication media (the telegraph) play as a component of identity and as forces of power and social change
Additionally, the following technology literacy components are included:
• Recognize the pervasiveness of technology in everyday life: Students will understand how the telegraph has shaped elements that impact their life, such as the creation of time zones
• Familiar with nature and limitations of engineering design process: Students will understand the basic process of building the telegraph, including laying wires to transmit signals. Will know that this basic format still underlies current internet infrastructure.
• Know ways technology has shaped human history and how people have shaped technology: Students will learn about how the telegraph was developed, how it impacted history, and through the concept of technogenisis, how it shaped humans.