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Electric Messages: Then and

Now

+What will we do today?

Send a message - using yesterday’s technology

Send a message- using today’s technology

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+The Titanic StoryOn the evening of 14 April 1912, in the wireless room of the Titanic, Phillips was sending messages to Cape Race, Newfoundland, working to clear a backlog of passengers' personal messages that had accumulated when the wireless had broken down the day before. Bride was asleep in the adjoining cabin, intending to relieve Phillips at midnight, two hours early.

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+The Titanic Story

Shortly after 9:30 pm, Phillips received an ice warning from the steamship Mesaba reporting a large number of icebergs and an ice field directly in the path of Titanic. Phillips acknowledged the Mesaba's warning and continued to transmit messages to Cape Race. The Mesaba's wireless operator waited for Phillips to report that he had given the report to the bridge, but Phillips continued working Cape Race. The warning was one of the most important warnings Titanic received, but for reasons no one is sure about, the warning was never delivered to the bridge.

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+The Titanic Story

After 11:00 pm, Phillips was again interrupted by another ship, this time the SS Californian. The Californian's only wireless operator, was reporting that they were stopped and surrounded by ice. The Californian was very close and the signal was strong and loud in Phillips' ears. Phillips quickly sent back, "Shut Up! Shut Up! I am working Cape Race," and continued communicating with Cape Race while Evans listened a while longer before going to bed for the night.

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+The Titanic Story

The Titanic struck an iceberg at 11:40 pm that night and began sinking. Bride had woken up and began getting ready to relieve Phillips when Captain Edward Smith came into the wireless room and told Phillips to prepare to send out a distress signal. Shortly after midnight Captain Smith came in again and told them to send out the call for assistance and gave them Titanic's estimated position. Phillips began sending out the distress signal, code CQD, while Bride took messages to Captain Smith about which ships were coming to Titanic's assistance. At one point Bride jokingly reminded Phillips that the new call was SOS and said "Send SOS, it's the new call, and it may be your last chance to send it."

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+The Titanic Story

After taking a quick break, Phillips returned to the wireless room, reporting to Bride that the forward part of the ship was flooded and that they should put on more clothes and lifebelts. Bride began to get ready while Phillips went back to work on the wireless machine. The wireless power was almost completely out when Captain Smith arrived and told the men that they had done their duty and that they were relieved. Bride later remembered being moved by the way Phillips continued working.

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+The Titanic

The “unsinkable” ship

They received warning messages, but The Titanic did sink

Help was very near, but Call for help was not received by the Californian, only 10 km away

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+The Task (1)

1. Build a device that uses Morse Code

1. Test the device by sending the messageSOS – Save our Souls

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+The Task (2)

1. Participant A: -Think of an emergency situation, then send a message explaining the situation and ask for help. Keep it secret

2. Participant B:-Once B understands the message report group and time taken on the flip chart – time from A starting to transmit to B understanding the message

RULE:

No speaking, but B may nod after each letter or word. Once B thinks he understands the message he must tell A what he understands

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+The Task (3)

1. Repeat the task reversing roles, but message must be different

2. Record time taken on Flip Chart

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+The Task (4)

1. Repeat the task using a mobile phone message can be the same

1. Record time taken on Flip Chart

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+ Summarising

1. A sends message to B using Morse Code

2. B sends message to A using Morse Code

3. A sends message to B text on Mobile phone

RULES

No speaking, but B may nod after each letter or word. Once B thinks he understands the message he must tell A what he understands

Record time from start of transmission tounderstanding the message

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+ Messages

Give examples of messages that are sent in everyday life today.

Explain and discuss Importance Reasons for secrecy and security How is security achieved? Accuracy requirements.

How do today’s messages differ from yesterday’s messages? Technology used Social requirements Spam and advertising

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+ History of Telegraphy Ancient: Optical: Smoke signals

1800: Optical: Semaphore

1832: Signal over Electrical Wires

1837: Morse Code: Morse & Vale

1891: World-wide cables

1896: Radio telegraph: Marconi over 6 km

Codes, modulation, multiplexing

1910: Printing telegraph

1920: Telex network

1970: Internet - Email

1991: World-wide web

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