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Telegraph key (also known as the Morse key) is a generic term for any switching device used primarily to send Morse code. Similar keys are used for all forms of manual telegraphy. Two common uses include the electrical telegraph over wires which activates a Telegraph sounder and radio telegraphy. Several variants exist. Download high resolution version (480x640, 43 KB)Telegragh keys , taken by User:Ultratomio at June 28, 2004(JST). ...
Download high resolution version (480x640, 43 KB)Telegragh keys , taken by User:Ultratomio at June 28, 2004(JST). ...
1922 Chart of the Morse Code Letters and Numerals Morse code is a method for transmitting information, using standardized sequences of short and long marks or pulses — commonly known as dots and dashes — for the letters, numerals, punctuation and special characters of a message. ...
Optical Telegraf of Claude Chappe on the Litermont near Nalbach, Germany Telegraph and telegram redirect here. ...
It has been suggested that this article or section be merged into Telegraphy. ...
A Telegraph Sounder is a device which produces an audible sound when connected to an operating electrical telegraph. ...
Wireless telegraphy is the practice of remote writing (see telegraphy) without the wires normally involved in an electrical telegraph. ...
Straight keys A straight key is the common telegraph key seen in old movies. It is a simple bar with a knob on top and a contact underneath. When the bar is depressed against spring tension, it forms a circuit and allows electricity to flow. Traditionally, American telegraph keys had flat topped knobs and narrow bars (frequently curved.) British telegraph keys had ball shaped knobs and thick bars. This appears to be purely a matter of culture and training, but the users of each are tremendously partisan.
The straight key is simple and reliable, but the rapid pumping action needed to send a string of dots (or dits as most operators call them) poses some significant drawbacks. Transmission speeds are limited to around 20 words per minute, and in the early days of telegraphy a number of professional telegraphers developed a repetitive stress injury known as glass arm or telegrapher's paralysis. Repetitive strain injury, also called repetitive stress injury or typing injury, is an occupational overuse syndrome affecting the tendons and nerves. ...
Fist All telegraphists unconsciously develop personal quirks, or characteristics, collectively called one's "fist". Experienced telegraphists can recognize one another as easily as they can recognize a voice. [1]
Alternative key designs The first widely accepted alternative key was the sideswiper or sidewinder, sometimes called a cootie key. This key uses a side-to-side action with contacts in both directions and the arm spring-loaded to return to center. A series of dits could be sent by rocking the arm back and forth. The alternating action produces a distinctive rhythm or swing which contributes noticably to the the user's fist. Although the sideswiper is seldom seen or used today, nearly all advanced keys use some form of side-to-side action.
Undoubtedly the most popular side-to-side mechanical keys is the semi-automatic key or bug, sometimes known by as a Vibroplex key, after the company that first manufactured them. When the paddle is pressed to the left it makes a continuous contact suitable for sending dashes (or dahs, as most operators call them). When the paddle is pressed to the right, a horizontal pendulum is set into motion which rocks against the contact points, sending a series of short pulses (dits) at a speed which is controlled by the position of the pendulum weight. A skilled operator can achieve sending speeds of 60 to 80 words per minute with a bug. Undoubtedly the most popular side-to-side mechanical Morse keys is the semi-automatic key or bug. The most popular brand was (and still is) the Vibroplex key, named for the company that first manufactured them in 1905. ...
Simple gravity pendulum assumes no air resistance and no friction of/at the nail/screw. ...
Like the bug, the electronic keyer operates sideways. When pressed to one side the electronics generate a series of "dahs" and when pressed the other way, a series of "dits". Most electronic keyers include a dit memory function which frees the operator from the need to perfectly time his transitions in the sequence dah-dit-dah. With dit memory, if the operator's keying action is about one dit ahead of the actual transmission, the keyer's output for each letter will be machine-perfect. An iambic keyer sports dual paddles, one for dit and one for dah; pressing both at the same time produces an alternating dit-dah-dit-dah sequence. Electronic keyers allow very high speed transmission of code.
ImageMetadata File history File links Download high resolution version (981x803, 659 KB) Bencher Paddles, fitted with a mini-audio connection (cropped version). ...
ImageMetadata File history File links Download high resolution version (981x803, 659 KB) Bencher Paddles, fitted with a mini-audio connection (cropped version). ...
Biambic, triambic, etc.. Keys offering one switch for dashes and another for dots were dubbed "iambic," but others misheard the term, interpreting it as "biambic." Thus keys with multiple switches have been dubbed "triambic", and beyond, i.e. a number of arbitrarily complex keyers were designed and built in the early 1970s for wearable computing. The most popular designs, the pentambic and septambic keyers, are still in widespread use today. Keyer for wearable computer designed and built for making lightvector paintings. ...
A wearable computer is a small portable computer that is designed to be worn on the body during use. ...
Odd uses Telegraph keys were once used in the study of operant conditioning with pigeons. Starting in the 1940s, initiated by B. F. Skinner at Harvard University, the keys were mounted vertically behind a small circular hole about the height of a pigeon's beak in the front wall of an operant conditioning chamber. Electromechanical recording equipment detected the closing of the switch whenever the pigeon pecked the key. Depending on the psychological questions being investigated, keypecks might have resulted in the presentation of food or other stimuli. Modern pigeon response keys are specially made switches but are still called "keys" due to their origins as telegraph keys. Operant conditioning is the modification of behavior brought about over time by the consequences of said behavior. ...
Pigeon redirects here. ...
1940 (MCMXL) was a leap year starting on Monday (the link is to a full 1940 calendar). ...
Burrhus Frederic Skinner Burrhus Frederic B. F. Skinner (March 20, 1904 – August 18, 1990) was an American psychologist and author. ...
Harvard University (incorporated as The President and Fellows of Harvard College) is a private university in Cambridge, Massachusetts. ...
An operant conditioning chamber (sometimes called a Skinner box after B. F. Skinner, its inventor) is an experimental apparatus used by psychologists to study operant conditioning in animals. ...
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