Talk:Alexanderson alternator
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A well written page not capable of much improvement.!--Light current 00:01, 27 March 2006 (UTC)
Tesla a competitor?
[edit]Didn't Nikola Tesla invent the "Alexanderson Alternator?" Tesla described experiments with high frequency multipole alternators at his several international lectures in 1892, and he used alternators as part of his high-power transmitter experiments prior to 1898. Critical question: what is the difference between Tesla's alternator patent 447,921 and others, versus Alexanderson's? Was it just a matter of marketing and publicity (where Alexanderson won the race to market, even though Tesla first invented the device?) --Wjbeaty 13:36, 3 October 2006 (UTC)
- That depends on what the meaning of "invent" is. I've read "My Inventions" and "Man out of Time" and it seems to me that nothing Tesla invented after the polyphase patents ever had much commercial success. I think the "purpose of radio communications" point is key; Tesla was too busy with his Wardenclyffe dreams to stoop to commercialization of a mere CW transmitter. However, I've learned to never cross the Teslaphiles on Wikipedia. An analysis of the claims of the respective patents would doubtless show many differences. --Wtshymanski 21:01, 3 October 2006 (UTC)
- Wtshymanski, your POV show clearly. Nikola Tesla's U.S. Patent 447920 had a frequency that was in the longwave broadcasting range (VLF band). Tesla continued research into higher frequency devices and, by early 1896, he attained the means to produce undamped (or "continuous") waves around 50,000 cycles per second for radio transmission. 172.162.29.30 15:55, 30 December 2006 (UTC)
- However, I've learned to never cross the Teslaphiles on Wikipedia. Lol. We're very scary. BOOGA BOOGA! Anyway, I thought Tesla was using exactly these devices for wireless communications experiments in Manhattan and later in Colorado. His goal of wireless power doesn't magically cancel out other accomplishments. What's more important: that an invention was the first of its kind, patented, and used? Or do you really think such issues become irrelevant, since selling the devices is more important?
- The situation appears to be this: Tesla patented a high-frequency alternator in 1891, and used it for high-power radio transmission experiments famous at the time. Then twenty years later, after memories have dimmed, Alexanderson patented an improved high-frequency alternator and used it for radio transmission. The edge of Alexanderson's rotor is different than Tesla's, his frequency was 10x higher than Tesla's, and his patent claims "higher power than other alternators of this type." (OTHER alternators? This WP entry says that Alexanderson was the inventor!) But maybe the 10x frequency increase was a critical change. --Wjbeaty 02:16, 4 October 2006 (UTC)
- Yea ... The edge of Alexanderson's rotor is different than Tesla's and his frequency was 10x higher than Tesla's. That is what you call progress. It's an critical improvement, but he wasn't the inventor of radio frequency alternators. Anyways, Fessenden followed up on Tesla's theoretical and practical groundwork (and mentioned him in some of his patents, IIRC [This is neat ... stubled on it ... U.S. patent 1,374,293, "Wireless direction finder" – April 12, 1921 ... mention Edison, Dolbear, and Tesla =-] ...]). Fessenden was the catalyst to have Alexanderson design the RF alternator which bear the latter's name (and one woulod have to ask would Alexanderson have done this himself if not for Fessenden). J. D. Redding 19:17, 23 January 2008 (UTC)
- Another neat patent ... U.S. patent 1,534,205, "Eliminating Distrubing Energy" ... cites resonate methods of Hertz and Tesla. Not real applicable here ... but just a note. J. D. Redding 19:41, 23 January 2008 (UTC)
- Then twenty years later, after the patents lapsed, Alexanderson patented an improved high-frequency alternator and used it for radio transmission. 172.162.29.30 15:55, 30 December 2006 (UTC)
- Yes, I think the people who bring an invention to the public and make it work on a regular useful basis have a better claim to be the inventors than laboratory stunts. "The value of an invention lies in the using of it", paraphrasing Edison. It's not like you could *ever* have walked up to Tesla's transmitter and sent a telegram to your Aunt Minnie - but a significant amount of the world's business was carried over Alexanderson alternators in their heyday. 10 kHz is an exceptionally lousy frequency for radio, as you can appreciate - and makes 100 kHz look very good; or at least enough better to make wireless communication commercial, instead of a stunt. We remember Ford and Daimler, not all those decadent aristos who fooled with steam carriages; Edison, not all the lab stunts with strips of platinum in jars that needed a full-time grad student to keep running; Marconi, not Tesla or Popov, as the founder of practical radio, etc. --Wtshymanski 17:54, 4 October 2006 (UTC)
- People who bring an invention to the public and make it work on a regular useful basis (eg., Telsa) have a better claim to be the inventors than those that just imporve on the original idea (eg., Alexanderson, Marconi, etc...). 172.162.29.30 15:55, 30 December 2006 (UTC)
- Hold on a sec. For other devices described on WP, do we declare one person as "Inventor," and then delete all the documented early history of the device prior to that inventor? Sounds like intentional distortion to me, and not appropriate to an encyclopedia. But that's what's happening here. --Wjbeaty 22:32, 14 January 2007 (UTC)
- If we want to present the history fairly, there were a whole lot of people besides Tesla who built high-frequency alternators before Fessenden: Elihu Thomson (1890), Solomons and Pike (1891), B. G. Lamm, Siemens bros., Epstein (1902), William Duddell (1905), as well as the contemporaneous machines of Count Arco and Joly. If the Tesla groupies bothered to research their subject they'd know this, but Tesla groupies don't do any research outside of reading Tesla's self-aggrandizing speeches and drooling over pictures of Wardenclyffe. Their insertion of their cult hero into articles as sole "inventor", ignoring the rest of the history of high-frequency engineering, is rampant UNDUE. --ChetvornoTALK 21:54, 7 October 2013 (UTC)
- This could be necroposting, but the thing is the principle of work of the Alexanderson alternator is totally different from the polyphase high frequency alternators that lots of people were using before Alexanderson and Fessenden. This alternator has NO windings in the rotor, unlike Tesla's work or the Goldschmidt or the Arco alternators, which were pretty regular alternators with frequency multipliers, one made by capacitors banks cleverly wired, the other by magnetic transformers. 190.139.209.199 (talk) 07:54, 3 April 2015 (UTC)
- Good point. Another reason Tesla should not be credited as "inventor". --ChetvornoTALK 10:30, 3 April 2015 (UTC)
- And Tesla was not the first. The first high frequency alternator was invented by Elihu Thomson in 1889. [1], [2], [3], [4]
- Good point. Another reason Tesla should not be credited as "inventor". --ChetvornoTALK 10:30, 3 April 2015 (UTC)
Radio transmitters based on high-frequency alternators
[edit]Perhaps the present article should move to a more general title, analogous to the "Incandescent bulb" rather than the specific "Edison carbon filament bulb." I'd recommend against it, since our goal should be to enlighten the non-experts and not confuse them with in-fighting ploys. Since WP has no other entry like "high frequency radio alternator," and since the term "Alexanderson alternator" is the long-accepted generic name for these devices, this article is the appropriate place for describing the complete historical development of this form of radio transmitter. Note well: nobody's suggesting that we delete this article and replace it by one called "Tesla Alternator." (grin!) So why are the Tesla references being deleted? By analogy, in an article about "Incandescent light bulb," it would clearly be both POV and inaccurate to try to delete information about Edison's failed predecessors such as Humphry Davy, Swan, etc. Rather than deleting refences to Tesla because Tesla's radio company failed, it's more honest and professional to describe the wireless alternator history accurately. Unless there are earlier inventors, Tesla was the first to publicly employ these devices for wireless ...but they certainly were ignored until Alexanderson. -Wjbeaty 22:32, 14 January 2007 (UTC)
- It's an arc lamp, not a radio! Where in "My Inventions" does Tesla claim invention of radio? Surely he'd mention it. --Wtshymanski 18:42, 15 January 2007 (UTC)
- See above. Tesla himself didn't think his alternator was of any use for radio communications - remember he was going to unite the world with the Wardenclyffe "World system"? WHy does the Wikipedia think this arc-lamp alternator is relevant to radio? Could I have a reliable reference to a book that actually says Tesla sent messages with his alternator? Rememembering also that Tesla didn't believe in "Hertzian waves", either! It's mentioned appropriately in passing as prior art but Tesla's alternator had no significance to radio, from what I have read. --Wtshymanski (talk) 18:23, 23 January 2008 (UTC)
- Wrong! ... Please read up on the "true wireless". He was developing his system for wireless communication. The work was in relation to wireless power transfer. He envisioned devices such as the crystal radio [which receives power from the signal].
- The arc-lamp alternator is relevant to radio. It's the 1st one that could produce such signals. A factor that played a part in Tesla being recognized by the US Supreme Court as the inventor of radio!!
- And you are wrong on your statement that Tesla didn't believe in "Hertzian waves". He understood that hertzian waves. Please read, "The Disturbing Influence of Solar Radiation On the Wireless Transmission of Energy", Electrical Review and Western Electrician, July 6, 1912. This is one of some of the material that Tesla recognized Hertzian waves ... but was disappointed by them [transverse waves die off quickly ... longitudinal waves from his resonator have a greater importance at the lower frequencies, IIRC]
- Please DO NOT removed sourced information because you do not understand the significance. Thanks. J. D. Redding 18:57, 23 January 2008 (UTC)
- Longitudinal waves...oh, I see...well, there's no arguing with longitudinal waves (which can't be EM radiation as I was taught). Did Tesla send messages with his alternator?
- The Wikisource reference is interesting too - right in the ihtroduction it says To him(Tesla) the Hertz wave theory is a delusion; it looks sound from certain angles, but the facts tend to prove that it is hollow and empty. He convinces us that the real Hertz waves are blotted out after they have traveled but a short distance from the sender. Obviously not the case - seen any stars at night? So, the source supports my understanding of the significance that Tesla didn't believe in Hertzian EM waves - I still have yet to see a coherent explanation of what it was Tesla believed, but it was not EM as we know it. I speculate it was this stubborness that lead Tesla into the wild goose chase that ruined his life. --Wtshymanski (talk) 00:00, 24 January 2008 (UTC)
- The 'Hertz wave theory' is a 'delusion'. A model that facts tend to prove hollow and empty for efficient use. Hertzian waves are 'blotted' out after they have traveled but a short distance from the transmitter. They drop off with the square (or is it the cube) of the distance. Tesla didn't believe in the efficiency of Hertzian EM waves (stars waste lots of power to "broadcast" their radiant energy) ... his method was superior ...
- Tesla used Maxwell's full equations ... not the heaviside-gibbs equations nearly everyone today uses (eg., "EM as 'we' know it"). He was using "molecular vortex model" of radiant energy.
- You can speculate (eg., push your POV) it was this stubborness that lead Tesla into the wild goose chase that ruined his life. John Stone Stone is remarked to have stated that if only his contemporaries understood what he was saying progress would have been quicker.
- As a side note ... Wtshymanski, please do not push a anti-teslian POV. Thanks. Sincerely, J. D. Redding 05:38, 28 January 2008 (UTC)
- Hertzian waves a delusion? Pretty strong delusion - ever seen the stars at night? Listend to the radio? Built a crystal set? Why have I never heard of the "molecular vortex model"? Where are the results? I've seen polyphase motors, and tesla gets credit for that (though if he hadn't invented a polyphase motor, doubtless someone else would have shortly after). I'm not "anti-teslian", I'm pro-reality or maybe anti-crank. Insisting all of science to date is wrong are, I'm sure, two of the hallmarks of crackpot science. --Wtshymanski (talk) 18:57, 28 January 2008 (UTC)
Needs a diagram
[edit]Something that I could sketch out in 30 seconds on a pad of paper is going to take me hours in Inkscape. This article needs a diagram. A hunt on Commons gave nothing usable the last time I looked. --Wtshymanski (talk) 13:46, 16 March 2011 (UTC)
Source for the table data?
[edit]Was wondering where the data in the table came from. Can someone add some sources? --ChetvornoTALK 01:21, 1 March 2020 (UTC)
- I found the original table on page 182 of Wireless Communication in the United States by Thorn L. Mayes, which was published by the The New England Wireless and Steam Museum, Inc. in 1989. I've updated the article page and added references. At some point someone added two Argentinian Telefunken alternators to the table, which aren't included in Mayes review, so I removed them. I also added a second Mayes table that reviews the seven Alexanderson alternators used by the U.S. military during and after WWII.--Thomas H. White (talk) 23:41, 7 March 2020 (UTC)
- I added an online reference (for easier verification) that appears to be a 1975 reprint of the same two tables by Thorn L. Mayes. I was initially skeptical of the numbers, because the text says "A typical alternator with an output frequency of 100 kHz", and so I expected about half of the actual broadcast frequencies to be above that 100 kHz number, but the actual broadcast frequencies in that table top out at 25.8 kHz. So is "100 kHz" not at all typical, and should be replaced with something more like "A typical alternator with an output frequency of 18 kHz"? Or is 100 kHz actually typical, and this article should mention "typical" Alexanderson radio stations nearer or above 100 kHz? --DavidCary (talk) 17:09, 3 June 2021 (UTC)