Talk:Beam tetrode

Talk page created
There seems to be better information on the history of the beam tetrode here http://en.wikipedia.org/wiki/6L6 Particularly the work of Harries in discovering "critical distance". I've put a copy of some relevant pages from Wireless World here if it's of use - http://sites.google.com/a/wepoco.com/self-aware/retro-geekery/valve-amplifiers/harries-august-1935 Regards, Michael Saunby. (talk) 09:41, 29 July 2008‎


 * September 2021. LSMFT has added several source citations and reconciled the Beam tetrode article with those sources. The Beam tetrode article is now superior to the 6L6 article, but more improvements are pending. LSMFT (talk) 20:14, 13 September 2021 (UTC)


 * So now I've provided authoritative sources for the 6L6 article and reconciled that article with the sources. The authoritative article on J.H. Owen Harries critical distance output tetrode is in a section of the Tetrode article. LSMFT (talk) 23:35, 14 September 2021 (UTC)

Reference to beam tetrodes having lower third harmonic distorion than pentodes
Radiotron Designer's Handbook, F. Langford-Smith ed., 4th edition, Wireless Press, Sydney 1954. Section 13.3 (x), page 569: "... includes types such as 6L6, 807 and KT66, which differ from pentodes principally in having sharper "knees" to their plate characteristics, more second harmonic but less third harmonic distortion." 2corner (talk) 11:26, 15 May 2014 (UTC)

Reason for the existance of the beam tetrode
The article currently says "A beam tetrode (also referred to as a "Beam Power Tube") is a type of vacuum tube specially designed to produce greater output power than a similar pentode." However, I was taught that the beam tetrode was invented as a way of producing a valve in the US with the benefits of a pentode over a tetrode but without infringing on the British patents on the supressor grid and thereby avoiding paying expensive licensing. The beam plates are not a traditional grid and therefore avoid the patents. This would imply that it was not specifically designed to improve on the pentode but merely to emulate one at lower expense than paying a license. I have not made an edit because I don't have a reference. Hopefully someone knows of a reference to sort this out, although the whole article needs referencing anyway. KX36 (talk) 14:37, 21 January 2012 (UTC)


 * You are correct. A reference to this is "History of the British Radio Valve to 1940"  Keith R Thrower, MMA International Ltd, Beaulieu 1992 p63 ISBN 0 9520684 0 0  G4oep (talk) 18:52, 7 January 2015 (UTC)


 * It is true that the primary goal was to evade Philips's patent. It is also true that the beam tetrode design has a greater output for a similar valve.  What is not immediately obvious is if the original designers of the beam tetrode also designed the device to have a greater output power.  They most probably did because this was the principal reason for aligning grids 2 and 3.


 * A beam tetrode could have been made using non aligned grids and it would have worked albeit with a greater loss of power to grid 2. Conversely, a regular pentode could be constructed with aligned grids 2 to achieve a greater output (but that would have been economically unviable as it would have required royalty payments to both Philips and EMI).  At the expiry of the patents, many pentode designs have been redesigned as beam tetrodes but not using aligned grids (to preserve the required grid 2 voltage - aligned grid beam tetrodes requiring a higher voltage).   Examples include Russian and Chinese versions of the EL34, and the pentode section of the EL82 produced by Mullard/Philips as both real pentodes and beam tetrodes.  86.153.133.193 (talk) 16:31, 13 February 2016 (UTC)

This Article Is Sound and Useful
This is a perfectly good article. Clear, concise and factually correct. I do not believe that additional citations should be required to maintain this article. The information is keenly accurate and the writing is clear, vibrant, friendly and most of all; effective English communication.

Additional citations would probably not do significant harm to this article; however, I think the writer’s time could be better spent expanding the article to include more information on this fascinating subject. —E.g., how were the manufacturing problems of the kink-less tetrode remedied? Simple things like a patent discrepancy have often been the historical catalyst to great scientific advances. This article has only scratched the surface of the scientific and manufacturing struggles to develop the modern KT tetrode, the 6L6 beam tetrode and the EL34-type pentode.

All of these devices played a vital role in the development of sound reproduction and radio in the 20th century. To this day, we continue to use all of these valves for audio and RF applications. The positive attributes of these specific valves has caused a revival of valve technology. Most engineers now realise that the principle of valves remains a useful science in our engineering tool box. There are hundreds of thousands of people making kits or designing their own modern valve gear because of the great worth of this science. This article is perhaps the only web source for this material I have seen. For the person searching for this information on the web, Wikipedia is the only entry that begins to present the subject with any level of completeness or objectivity and correct science. Removing this article from Wikipedia would be a great loss.

I most fear this article being withdrawn because it would be a great loss of useful and correct information. I.e., the bottom line of a Wiki article, or so I thought. Plus, Wikipedia would lose a vital, sound, useful and well written article. This is not a marginal article. It is amply sourced and well seeded with citation. Many of the citations are inane and unnecessary, but this is what the Wikipedia controlling personnel clique seem to want. The Wiki board’s officious obsession with over-citation and source reference is not useful, traditional or productive. It seems to be the product of an insular Wiki board or directors.

I am not sure if the favour for over citation and sourcing is the result of over-blown egos, “control freaks”, or what, but if not halted, this condition will surely cause Wikipedia’s eventual downfall. Do people understand that ALL Wiki articles are works in progress and are NEVER considered complete? This is the greatest advance over the traditional encyclopaedia that Wikipedia has top offer. I plead with the Wiki powers NOT to withdraw this article.

PS: I suggest all Wiki readers and contributors read volumes of the Encyclopaedia Britannica for better instruction on how encyclopaedia entries should be written. If Wiki is looking for an effective writing style guide they need go no further than "The Elements of Style" by Strunk and White and classic Encyclopaedia Britannica. Wikipedia has a bad habit of making their article requirements senselessly ridged and bureaucratic.

I am an Electronic Engineer and Historian. I have a long lived interest and passion for the overwhelming technology advances achieved by the RCA Victor Company during the 1920s-1950s. Particularly in Radio and Audio, no single company made more advances, inventions and significant contributions to Man’s base of knowledge on this subject than any other commercial enterprise on Earth. — Preceding unsigned comment added by Bixlives! (talk • contribs) 07:31, 17 October 2012 (UTC)


 * Picture of Beam Triode not appropriate


 * The picture of a beam triode is not very relevant to the article (beam TETRODES).
 * A better choice would be a picture of a 6L6G, 807, 6V6GT, KT66 or KT88.

2corner (talk) 10:48, 8 January 2015 (UTC)


 * I agree with you about articles that discuss technology that has passed us by. The main obstruction to writing about obsolete technology is finding those pesky references.


 * Some years ago, someone produced a draft article on how De Forest's audion worked (the forerunner of the vacuum triode (though it wasn't a vacuum triode and worked completely differently). Unfortunately I cannot remember where this draft article was - and I doubt that it still exists.  Although the author seemed to have a good knowledge of how the device worked (in that the explanation made sense and explained all the features the device had), I recall well that he or she was prevented from creating an article out of it because of those darned references - which I have to concur are impossible to find.  86.153.133.193 (talk) 16:46, 13 February 2016 (UTC)

See also: Tetrode
I trust that you will not object to the addition of this link. It seems that your page, & the material on Beam Tetrode in 'Tetrode' are complementary, and both might be interesting to a reader of these pages. G4oep (talk) 11:20, 8 January 2015 (UTC)
 * That's not the usual place to insert a "see also" section. The Manual of Style is long and tedious to read, but looking at other articles for examples is probably best when trying something for the first time.  If something is linked in the text, it's not usual to put it in a "see also"; the presumption is that the interested reader has already clicked on it. "See also" is useful if there's a pertinent or tangential topic that might be of use to the article reader, but that somehow hasn't gotten mentioned in the text yet. Too many "see also" references in a section are usually a sign that the article isn't comprehensive enough.  To my way of thinking, based on no Wikiality whatsoever, if someone has split the "see also" into columns, either the article needs more content or there's a lot of irrelevancies in the see-also section. --Wtshymanski (talk) 15:04, 8 January 2015 (UTC)