Navy League Summer Camp Semaphore Manual

Transcription

1 Navy League Summer Camp Semaphore Manual

2 Contents Definition of Semaphore... 3 History of Semaphore... 3 Definition of Phonetic Alphabet... 6 Phonetic Alphabet the Navy League uses... 7 Semaphore What you see... 8 Semaphore - What you send... 9 Message format... 10

3 Definition of Semaphore 1. An apparatus for conveying information by means of visual signals, as alight whose position may be changed. 2. Any of various devices for signaling by changing the position of a light, flag, etc. 3. A system of signaling, especially a system by which a special flag is heldin each hand and various positions of the arms indicate specific letters, numbers, etc. History of Semaphore Optical telegraphs or signaling devices have been traced back to ancient times (using torches) and were the fastest systems to convey messages over long distances. These telegraphs could have since been in the form of torches, smoke signals and eventually semaphore towers. Semaphore towers used large blades/paddles to convey messages. These messages were decoded based on the fixed positions of these arms and could transmit signals up to 150 miles in two minutes using multiple towers. The semaphore tower/semaphore line design was first thought up by Robert Hooke in 1684 and submitted to the Royal Society. The system was not implemented though due to military concerns. However, this did lead to Claude Chappe developing the first visual telegraph in 1792 eventually covering much of France via 556 stations. In France, this was the primary source of communication for military and national applications, until it became more widely used in the 1850 s. Designs varied between using shudders open and closed to holes being open and closed, but Chappe s design became the most widely used semaphore design.

4 Chappe s design used large towers that had a single crossbar with large pivoting arms at the ends and were spaced as far as part as the eye could see. The crossbar could be used in 4 different positions while the arms could be in 7 different positions each, for a combination of 196 (4x7x7) characters. These 196 characters could be combined to create a multitude of messages and phrases. Some have estimated that there were as many as 9,999 different codes created. Many other takes of semaphores became created, including the naval signaling code flags which are still used today. These flags could be used in combination to become different words and messages and thus not have to spell out each word since messages were usually needed to be displayed quickly. This system however proved to be slow during battle since these flags were hoisted to the top of the ship for display. Even Napoleon used one design to communicate to his army strategies and locations of his enemies. These semaphore stations were so successful that the French government rejected Samual Morse s first proposals of the electrical telegraph, citing that its design was flawed by wires being able to be cut easily. These visual messaging systems eventually led to semaphore flags. These flags were used in the same way that the arms were used on the semaphore towers different fixed positions mean different messages. Semaphore flags were primarily used for naval applications to communicate message between boats. It proved to be a very useful tactic during battles, most famously the Battle of Trafalgar during the Napoleonic Wars. Today these flags have become smaller and are usually mounted to small dowels or poles to allow them to be seen easier. Maritime use flags are red and yellow (or the OSCAR) flag and while in land use, the flags are blue and white (or the PAPA) flag. Even though they are not in use much anymore, they still serve for some boats and ships.

5 So why did we get rid of them? Well, there were two critical downfalls of all the systems: 1. They had no secrecy. Everyone within visual distances could see the message and therefore react to it. This proved to be one of the design s most fatal wartime attributes. 2. They were practically invisible at night time and during heavy fog and rain. Both of these reasons lead to the electrical telegraph and Morse Code, both invented by Samuel F.B. Morse. So, the next thing you know, we went to electrical telegraphs, pony express, telephone, radio, television, computers, fax machines, satellite televisions, cellular phones and the internet. What is next to come in communication? I for one cannot even begin to imagine all of the amazing devices we will see in the future. The one thing I do know is that ultimately semaphore flags and towers inspired all designs since.

6 Definition of Phonetic Alphabet The NATO phonetic alphabet, more accurately known as the International Radiotelephony Spelling Alphabet and also called the ICAO phonetic or ICAO spelling alphabet, as well as the ITU phonetic alphabet, is the most widely used spelling alphabet. Although often called "phonetic alphabets", spelling alphabets are not associated with phonetic transcription systems such as the International Phonetic Alphabet. Instead, the International Civil Aviation Organization (ICAO) alphabet assigned code words acrophonically to the letters of the English alphabet so that critical combinations of letters and numbers can be pronounced and understood by those who transmit and receive voice messages by radio or telephone regardless of language barriers or the presence of transmission static. The 26 code words in the NATO phonetic alphabet are assigned to the 26 letters of the English alphabet in alphabetical order as follows: Alfa, Bravo, Charlie, Delta, Echo, Foxtrot, Golf, Hotel, India, Juliet, Kilo, Lima, Mike, November, Oscar, Papa, Quebec, Romeo, Sierra, Tango, Uniform, Victor, Whiskey, X- ray, Yankee, Zulu.

7 Phonetic Alphabet the Navy League uses The Navy League uses the same phonetic alphabet as NATO. Below is a chart with the Phonetic Alphabet. A - ALPHA C - CHARLIE E - ECHO G - GOLF I - INDIA K - KILO M - Mike O - Oscar Q - Quebec S - Sierra U - Uniform W Whiskey Y - Yankee B - BRAVO D - DELTA F - FOXTROT H - HOTEL J - JULIET L - Lima N - November P - Papa R - Romeo T - Tango V Victor X - X-ray Z - Zulu

8 Semaphore What you see ALPHA Bravo Charlie Delta Echo Golf Foxtrot Hotel India Juliet Kilo Lima Mike November Oscar Papa Quebec Romeo Sierra Tango Uniform Victor Whiskey X-Ray Yankee Zulu

9 Alpha Semaphore - What you send Bravo Charlie Delta Echo Foxtrot Golf Hotel India Juliet Kilo Lima Mike November Oscar Papa Quebec Romeo Sierra Tango Uniform Victor Whiskey X-ray Yankee Zulu Picture is seen from the back of sender

10 Message format In Ontario Division we only do semaphore as part of our competitions. We follow the ODI 2305 Rev 02. Each message must be of the same number of letters/breaks to a total of 160 characters. Each team has four members they are the following. 1. Reader 2. Sender 3. Receiver 4. Recorder At the competition we do two messages each message is different. When the second message is sent the positions switch. This makes it so that every member gets to do something different and it allows the cadets to be proficient in all positions. The Reader must say the letters using the phonetic alphabet to the sender and the Receiver must also use the phonetic alphabet when telling the recorder. The Receiver will write the message out on the sheet provided and will put one character in each box. If they make a mistake they can cross out the letter and put the correct one above the box. For breaks the receiver can do any of the following. 1. A large letter X (filling the entire block) 2. A slashed line 3. A block shaded in 4. Or left blank Any other character will be assessed a one point penalty for each use. On the next page is an example of the sheet that is currently being used for Ontario Division s competition. Each line has spaces for 21 characters. For our competitions the last line only uses 13 spaces making a total of 160 characters.

11 ONTARIO DIVISION SEMAPHORE COMPETITION CORPS.... SQUADRON.... DATE... CORRECT I IIII II III II IIII II II I I O Number of letters/breaks = 160 Accuracy total = X 100 = % Minus errors Accuracy total Divided by 160