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My real-life name is Colin Hall. I am a retired electronics engineer and project manager. For many years I did not reveal my real-life identity on Wikipedia so that I could edit here without any concern over what my employers might think. Not that I have ever written anything about any company I worked for, or the products they make, except extremely tangentially. It was just that knowing an employer might be reading might subconciously colour my writing, which I did not want to happen. What I write is entirely for the purpose of improving Wikipedia, and I did not want any other consideration to creep in.

Wikipedia articlesEdit

I have written mostly on technical subjects, with a strong bias to the history of technology. Some of my earliest work was on 1920s filter designs which were widely used at one time, but were almost entirely missing from Wikipedia. As this was an area I knew about, it led to my first big tranch of article creation. They weren't my very first articles—I think that was on games and puzzles which also interest me, especially if they are mathematically or logic orientated. But I haven't written anything in that field recently. The majority of electronic/electrical engineering articles that have achieved Featured Article status to date have been written by me.

I have occassionaly dabbled in writing medical articles, especially when there is an electrical aspect to the subject. I am especially attracted to doctors who have carried out bizarre procedures that never caught on. In one year, much to my surprise, I got an award (barnstar type thing) for being one of the top medical editors. I am also still an active ice skater, but have contributed only a few sentences to Wikipedia in that field.


I will not tread your dusty path and flat,
denoting this and that by this and that,
your world immutable wherein no part,
the little maker has with maker's art.
I bow not yet before the Iron Crown,
nor cast my own small golden sceptre down.

People who put in all the commas betray themselves as moral weaklings with empty lives and out-of-date reference books.

Referring to Wikipedia being like the proverbial million monkeys with a million typewriters eventually churning out the complete works of William Shakespeare;

We aren't trying to produce something as difficult as poetry, but on the other hand we aren't as polite as monkeys, so it evens out.

You do not really understand something unless you can explain it to your grandmother.

I agree with virtually everything he says, but find myself wanting to smack him for his intolerance.

— Simon Hattenstone on Richard Dawkins[2]

I prefer gas lighting

— Oliver Heaviside, a major figure in the development of electrical theory, The Electrician, p. 452, 31 July 1896.

The history of the Universe has been summed up thusly: "Hydrogen is a light, odorless gas, which, given enough time, turns into people."

— John P. Wiley Jr, quoting Edward R. Harrison[3]

Stuff wot i have done to WikipediaEdit

Some editors will put articles on their lists to which they have merely made a small contribution. All the articles and images shown here and on the linked lists have been created by me from scratch, or at most from an insignificant stub.

  Otto Julius Zobel
An original drawing by Zobel of a band-pass filter used for impedance matching.

Otto Julius Zobel (October 20, 1887 – January 1970) was a design engineer who worked for the American Telephone & Telegraph Company (AT&T) in the early part of the 20th century. Zobel's work on filter design was revolutionary and led, in conjunction with the work of John R. Carson, to significant commercial advances for AT&T in the field of frequency division multiplex (FDM) telephone transmissions.

Zobel invented the m-derived filter and the constant-resistance filter, which remains in use today. With Carson he helped to establish the nature of noise in electric circuits, concluding that—contrary to mainstream belief—it is not even theoretically possible to filter out noise entirely and that noise will always be a limiting factor in what it is possible to transmit. Thus, they anticipated the later work of Claude Shannon, who showed how the theoretical information rate of a channel is related to the noise of the channel.

  Analogue filter

Analogue filters are a basic building block of signal processing much used in electronics. Amongst their many applications are the separation of an audio signal before application to bass, mid-range and tweeter loudspeakers; the combining and later separation of multiple telephone conversations onto a single channel; the selection of a chosen radio station in a radio receiver and rejection of others.

Analogue filters have played an important part in the development of electronics. Especially in the field of telecommunications, filters have been of crucial importance in a number of technological breakthroughs and have been the source of enormous profits for telecommunications companies. It should come as no surprise, therefore, that the early development of filters was intimately connected with transmission lines. Transmission line theory gave rise to filter theory, which initially took a very similar form, and the main application of filters was for use on telecommunication transmission lines. However, the arrival of network synthesis techniques greatly enhanced the degree of control of the designer.

  More featured articles...
  More Good Articles...
Zobel network
BBC engineers equalising audio landlines circa 1959 using adjustable Zobel networks

Zobel networks are a type of filter section based on the image impedance design principle. They are named after Otto Zobel of Bell Labs who published a much referenced paper on image filters in 1923. The distinguishing feature of Zobel networks is that the input impedance is fixed in the design independently of the transfer function. This characteristic is achieved at the expense of a much higher component count compared to other types of filter sections.

Zobel networks were formerly widely used in telecommunications to flatten and widen the frequency response of copper land lines, producing a higher quality line from one originally intended for ordinary telephone use. However, as analogue technology has given way to digital they are now little used.

Minimum orbit intersection distance
The orbit of (4953) 1990 MU, which, with a MOID of 0.0276 AU, is classified as a Potentially Hazardous Object

Minimum orbit intersection distance, abbreviated MOID, is a measure used in astronomy to assess collision risk between astronomical objects. It is defined as the distance between the closest points of the osculating orbits of the two bodies in question. Of greatest interest is the risk of a collision with Earth; the MOID between an object and Earth is called Earth MOID. Earth MOID is often listed on comet and asteroid databases such as the Jet Propulsion Laboratory's Small-body Database. However, MOID can be defined with respect to other bodies as well: Jupiter MOID, Venus MOID and so on.

An object is classified as a Potentially Hazardous Object (PHO) – that is, posing a possible risk to Earth – if, among other conditions, its Earth MOID is less than 0.05 AU.

More articles...
I wrote this article on what I thought was an obscure astronomical metric. It has since acquired well over 1,000 incoming links! Templates... and categories created...
  Mechanical filter
A mechanical filter using disc flexual resonators and magnetostrictive transducers.

A mechanical filter is a signal processing filter that is used in place of an electronic filter but for the same task, usually at radio frequencies. At the input and output of the filter there are transducers which convert the electrical signal into, and back from, a mechanical vibration.

The components of a mechanical filter are all directly analogous to the various elements of an electrical circuit. It is therefore possible use electrical network analysis and filter design techniques on mechanical filters which is a great convenience for electrical engineers in the design of these circuits. Any of the classic frequency responses can be obtained with the right choice of component values.

Murphy drip
A Murphy drip apparatus

A Murphy drip is a rectal infusion apparatus to administer the medical procedure of proctoclysis, also known as rectoclysis. During the procedure, an end of the Murphy drip is inserted into the rectum and large quantities of liquid are infused into the rectum drop-by-drop. Prior to fluids or medicines being given intravenously, the Murphy drip and hypodermoclysis were the prime routes to administer fluids such as for replacement when patients could not be fed by mouth. Wisconsin surgeon John Benjamin Murphy introduced the drip method of saline infusion per rectum in the treatment of peritonitis.


More contributions...

More images (MANY more)...
  Did you know... that volunteers at the Sorby Research Institute were made to wear the dirty underpants of scabies sufferers?
  Did you know... that surgeon Dr. Evan O'Neill Kane signed his handiwork by tattooing the letter K in Morse code on his patients in India ink?
More DYK features...

My shortcutsEdit


  • Cornell University Library e-print arXiv
  • Physics factbook
  • WP:Library
  • European Patent Office
  • http://www.freepatentsonline.com
  • Langenscheidt Routledge German Dictionary of Physics ISBN 0415173388
  • German Technical Dictionary ISBN 0415335876, Google books preview, Amazon search inside
  • Meriam-Webster's dictionary of English usage
  • British Museum search by object ID number
  • http://downforeveryoneorjustme.com/
  • MLA citation style from Long Island University
  • How to cite a patent
  • BSTJ index
  • Bell System technical journal at the Internet Archive. Extensive journal index at The Online Books Page
  • MeasuringWorth, for when {{tl:inflation}} is not appropriate.
  • Library of Congress copyright renewals at the University of Pennsylvania.

Useful essays and discussionsEdit


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  1. ^ Eats, Shoots and Leaves, pp97-98, Gotham Books (2004), ISBN 1-59240-087-6.
  2. ^ Hattenstone, Simon (10 February 2003). "Darwin's child". The Guardian. Retrieved 20 July 2018. CS1 maint: discouraged parameter (link)
  3. ^ wikt:thusly citing Smithsonian Magazine