Keyer
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Keyergrip.jpg
A keyer is a device for signaling by hand, by way of pressing one or more switches. Modern keyers typically have a large number of switches but not as many as a full size keyboard, i.e. most modern keyers have more than four switches but less than 50. A keyer differs from a keyboard, in the sense that there is no "board", i.e. the keys are arranged in a cluster. A keyer may take the form of a single telegraph key for keying Morse code. In this use, the term "to key" means to turn on and off a carrier, typically, e.g. it is said that one "keys the transmitter" by interrupting some stage of amplification with, for example, a telegraph key.
Morse code was an attempt at serial communication, which in more modern times has been, to a greater or lesser degree, automated. In a completely automated teletype system, the sender presses keys to send an ASCII data stream to a receiver, and computation alleviates the need for timing to be done by the human operator. In this way, much higher typing speeds are possible.
Septambic_key_numbering.jpg
So-called "Iambic Keyers" became popular, in telegraphy, in the 1960s in which the "dot" and the "dash" are separate keys. In the 1970s when this concept was introduced to inventor Steve Mann, it was mistakenly heard by him as "biambic" so he generalized the term to include various polyambic/multiambic keyers, such as a pentambic keyer (5 keys, one for each finger and one for the thumb), and septambic (3 thumb buttons on a handgrip), for use with a portable backpack based computer system that he invented for photographic lightvectoring (http://wearcam.org/dusting/). Around the same time, others developed chording keyboards that were intended to be used while seated (e.g. multiple keys but mounted to a board rather than a portable grip).
Twiddlerglog.jpg
Such keyers, used with wearable computers, are typically one-handed grips. Unlike keyBOARDs, the wearable computer keyer has no board upon which the switches are mounted Additionally, by providing some other function (e.g. simultaneous grip of flash light source and keying) the keyer is effectively hands free, in the sense one would still be holding the light source anyway.
See also
External links
- Intelligent Image Processing (http://wearcam.org/textbook.htm) (See Appendix on keyers)
- How to make your own custom-molded perfect-fit keyer (http://wearcam.org/septambi/)
- Keyers to the Castle (keyers for daily wearable computer use) (http://about.eyetap.org/library/weekly/aa120400a.shtml)
- Summary of keyers, commercially made keyers, other links, etc. (http://about.eyetap.org/tech/keyers.shtml)
- Another homemade one-handed keyer (http://www.chordite.com)
- Wearable keyer suitable for QRP use (http://electronicsusa.com/mk36.html) (leg mount accessory)