Talk:Telautograph

Should the word occurrences really be so badly misspelt (occurances) in the quote? I have no way of checking the original, but it doesn't seem very likely. --Zundark 09:09, 21 Dec 2003 (UTC)

"Gray was also famous for having submitted his patent application a few hours after Bell had submitted his application for the telephone". This is debunked in the article about Gray. —Preceding unsigned comment added by 85.93.243.11 (talk) 15:39, 27 December 2007 (UTC)

telautograph question

I found a stock certificate in this invention. Is it worth any thing at this time? —Preceding unsigned comment added by 68.0.197.231 (talk) 20:35, 7 June 2008 (UTC)

Omnifax 1971-1992

Danka seemed to erase Omnifax's history pretty effectively after they closed 8700 Bellanca Avenue and moved the headquarters to Texas. Omnifax was a pretty major fax company through the 80s and early 90s, wasn't it? Their solid Hitachi thermal machines were everywhere. 9S, G35, G36, G38, G66, G77, G88. Even though they were owned by a Supermarket and Real Estate company during that period, or whatever Arden-Mayfair was, weren't they a major player during the time that facsimiles became common home office and home appliances, or was it just my imagination?

I can't find any history on the Internet about Omnifax being a serious fax company, but that's not because they weren't. I don't think. Does anyone else remember?Rcmpvernon (talk) 04:28, 23 June 2009 (UTC)

Potentiometers are variable resistances

They don't act as signals/voltage generators Ebaychatter0 (talk) 00:58, 6 November 2012 (UTC)

Yes, I also think that the mention of potentiometers is erroneous. The text in Patent US 386815 A says specifically that the inventor sought to improve the limitations of potentiometer-controlled devices by using a pulsed control circuit: "The transmitting-pen is connected to operate circuit making and breaking devices, termed interrupters, located in two electric circuits and arranged to interrupt the currents passing over the respective circuits at shortintervals, producing pulsations therein as the pen is moved in two directions crosswise of each other in forming characters, the number of pulsations in the respective circuits being determined by the distance which the pen is moved in the respective directions. These two circuits pass through the receiver andinclude electro-motors, also hereinafter termed receivingmagnets, the armatures of which act through suitable connections to impart a step-by-step movement to the receiving-pen in two directions crosswise of each other, the number of steps in each direction being determined by the number of times the respective circuits are interrupted." Should I update the article to reflect this? -JL — Preceding unsigned comment added by 165.225.68.49 (talk) 14:00, 9 November 2017 (UTC)

I fixed this by replacing "potentiometers" with "circuit interrupters". I also removed the word "analog". It's not 100% straightforward to assess whether or when Gray ever used analog telautographs, because patents like US494562 (1893), US668890 (1901), and US924512 (1907) show that he and his company actively researched and developed analog systems, but early extant instruments such as are clearly the stepping digital type and bear only digital system patent numbers (patent numbers 386814, 386815, and 461470 are visible on the right hand medallion of the receiver in the photo). InductorMan2 (talk) 19:02, 13 October 2023 (UTC)

After doing a ton of research I've made a major overhaul of this page, mostly focused on technical aspects of the mechanism and how the devices worked. Most of the changes are very clearly substantiated by the references included in the article. To summarize, the prior art was analog/rheostats, Gray went digital/pulse encoders, and then his competitor/former assistant Ritchie went analog/rheostats again, and then Gray's company (where he no longer worked) followed suit and later devices were all analog (incidentally using graded potentiometers rather than rheostats, but I didn't include that in the article because too technical for general interest).

I also removed the claim that Ritchie's version could simultaneously do telephone and telautograph. There are plenty of references stating that his devices automatically switched between the two, but only one (Huurdeman 2003, which actually I am unable to access) from the original article which apparently said they were simultaneous. I still haven't removed the other claim that apparently came from this reference that it was the "first facsimile machine that used horizontal and vertical bars", but I probably should, because the Cowper invention referred to in the 1879 Scientific American citations clearly also uses horizontal and vertical bars and predates this.

I removed the "rotating drum" references because Gray himself describes the prior art as constantly moving strips of paper, and from my own reading I know that rotating drum facsimile machines are a completely different technology with functionality much more akin to actual fax machines, and definitely not what Gray was trying to do.

I also want to substantiate my claim that the 1893 machines Gray exhibited used the exact mechanism shown in Pat. US491347. I'm basing this off of an interpretation of the following bottom view photograph of a Telautograph from the Smithsonian American History Museum. Other images of this device match the images in contemporary accounts like the 1893 Manufacturer and Builder article.

https://ids.si.edu/ids/deliveryService?id=NMAH-AHB2006q17546

The linear magnetic clutch plates which appear only in that patent are visible through the base. The two linear brass brackets support the four plates, and the second one from the left is knocked out of place and visible in a diagonal position. The main page containing all of the images of this device can be found here:

https://www.si.edu/object/gray-telautograph-receiver-patent-s-386814-and-386815:nmah_712471

InductorMan2 (talk) 16:31, 21 October 2023 (UTC)

References

State of technology around 1965-1970

I just began re-reading the novel "Airport" today, and in the first chapter, Arthur Hailey mentions the Tel Autograph (two words) as part of the equipment used by the Snow Desk. For the first time, I actually wanted to find out what the term means, and I get the impression it is some sort of facsimile device for written or drawn materials.

There are pictures here and by means of a web search, but they are immensely old versions. It would make no more sense for them to be in use in 1967 than for Danny Farrow (character) to be using Alexander Graham Bell's early telephone models. I was hoping someone could come up with a photo of a commercial model that might be in common use in the 1950s and 1960s.

Today, I assume, a fax machine would be used to produce a hard copy for critical-situation use by the recipient, and hard copy for the originator for later inquiry or investigation.

So, can anyone out there come up with a picture of a "modern" (1960s) Telautograph? GBC (talk) 04:07, 10 February 2013 (UTC)