Wikipedia:Featured article candidates/Planar transmission line/archive1


 * The following is an archived discussion of a featured article nomination. Please do not modify it. Subsequent comments should be made on the article's talk page or in Wikipedia talk:Featured article candidates. No further edits should be made to this page.

The article was promoted by Sarastro1 via FACBot (talk) 13 February 2019.

Planar transmission line

 * Nominator(s): SpinningSpark 12:47, 1 December 2018 (UTC)

This article is about a form of transmission line widely used in electronics. It is of high importance in the field of microwave transmissions. It has been through GA and Peer Review and is a comprehensive overview of the technology. Electrical engineering is under-represented at FA, as is engineering generally. Hopefully, this article can help to correct that. SpinningSpark 12:47, 1 December 2018 (UTC)

Image review


 * File:Planar_modes.svg: what is the source of the data presented in this image? Nikkimaria (talk) 02:17, 2 December 2018 (UTC)
 * The sources are named in the reference at the end of the caption and in the file description. SpinningSpark 09:22, 2 December 2018 (UTC)


 * Ah, I missed the section underneath the licensing tag - suggest either moving up to the Source section of the summary, or at least providing a pointer there. Nikkimaria (talk) 15:04, 2 December 2018 (UTC)

Comments by Mike Christie
I was the GA reviewer, and am glad to see this here. It's dauntingly technical, but we need articles on this sort of topic, even though there's a limit to how accessible they can be made. When I promoted this to GA I was confident the material was well-organized and coherently presented, so I'm going to look mostly at prose clarity. -- More when I can. Mike Christie (talk - contribs - library) 12:06, 4 December 2018 (UTC)
 * ...millimetres. Hence the need for transmission lines within a circuit. We haven't yet said transmission lines are needed in circuits, only that they are used, so I'd suggest "Hence transmission lines are needed within circuits".
 * Done. SpinningSpark</b> 00:29, 4 December 2018 (UTC)
 * There are several different types of planar transmission line. The earliest type of planar transmission line was conceived...: some repeated wording here. Since "earliest type" implies there was more than one type, I think you could just cut the first sentence.  Alternatively, you could change the second sentence to start "The earliest was conceived..." but I think that's clumsier.
 * Done. The repetition is a result of replacing "forms" and "formats" with "types" after comments at the peer review. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 00:29, 4 December 2018 (UTC)
 * Many of these types have a narrower bandwidth and in general they produce more signal distortion than pairs of conductors: suggest "and in general produce more".
 * Done. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 00:58, 4 December 2018 (UTC)
 * Is there a suitable link target for "loss" at the end of the second paragraph of the lead? I had a look and couldn't find anything obvious.
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 13:51, 4 December 2018 (UTC)
 * Lumped passive components are often impractical at microwave frequencies for this reason, or because the values required are impractically small to manufacture. This sentence gave me some trouble in the GA review, and I've reread your explanation there. I think the key point is that lumped passive components are impractical because of their size; the fact that e.g. a desired impedance in a component in microwave circuits could require an impractically small physical size for the component could be relegated to a footnote.  How about "Lumped passive components are often impractical at microwave frequencies for this reason, but they can be replaced by a pattern of transmission lines that provides the same function within the circuit", with a footnote for the omitted text if necessary?
 * I'm reluctant to omit or footnote that. Both reasons can apply.  Even in the same design (to different components).  The prose may be improvable, but I think both reasons should stay. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 00:58, 4 December 2018 (UTC)
 * OK, I'll think about it some more. Mike Christie (talk - contribs - library) 02:44, 5 December 2018 (UTC)
 * I made it "either for this reason", which makes it clearer that the second reason is unrelated to the prior explanation. I think that's what was bothering me. Mike Christie (talk - contribs -  library) 11:19, 7 December 2018 (UTC)
 * The most widely used planar types are stripline, microstrip, suspended stripline, and coplanar waveguide. It's not clear whether this refers to the previous sentence ("...planar types of dielectric waveguide") or the subject of the article.
 * Clarified <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 13:51, 4 December 2018 (UTC)
 * Usually, steps are taken to suppress all modes except the operational one: does "operational" mean "having the intended functionality"? If so I think something like "desired" or "intended" would be clearer to a lay reader.
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 13:51, 4 December 2018 (UTC)
 * ...it can be used at low frequencies, all the way down to zero (DC): suggest "(i.e. DC)".
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 13:51, 4 December 2018 (UTC)
 * Because of this, ideal TEM transmission lines do not suffer from a form of distortion called dispersion. Dispersion is where different frequency components travel at different velocities resulting in the wave shape (which may represent the transmitted information) becoming "smeared out" in the direction of the line length. Suggest "Because of this, ideal TEM transmission lines do not suffer from dispersion, a form of distortion in which different frequency components travel at different velocities. Dispersion "smears out" the wave shape (which may represent the transmitted information) in the direction of the line length."
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 15:04, 4 December 2018 (UTC)
 * The conductors consist of flat strips, and there are usually one or more ground planes parallel to the flat surface of the conductors. This is the only sentence in the early part of the article to give a general description of the elements of planar transmission lines.  Can we add a little more detail?  It seems every design uses a dielectric substrate in some way, for example.  A few words here would prepare the reader for later sentences like "Some planar types, notably microstrip, do not have a homogeneous dielectric".
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 15:04, 4 December 2018 (UTC)
 * ...classified as either transverse electric (TE) or transverse magnetic (TM) (also called respectively H and E modes) according to whether, respectively, all of the electric field, or all of the magnetic field is transverse Can we avoid two consecutive uses of "respectively"?
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 15:04, 4 December 2018 (UTC)
 * The first paragraph on LSE and LSM modes seems to repeat itself at the end. Could we cut the last sentence, and change an earlier sentence to say "It turns out that the LSE and LSM modes..."?
 * See next point
 * Do we need the last two sentences of that section? We've already used the term "hybrid modes" at the start of the section and we don't use "HEM" anywhere else in the article.  Could the definition of "hybrid" be given earlier, instead?  Perhaps in the "Transverse modes" section where you say "there is always a longitudinal component"?
 * I'm thinking of entirely recasting this section in a much simpler form. I propose to entirely remove the discussion of the derivation from Maxwell's equations and the notation arising.  This may be too much detail for an overview article.  The trouble is that this information appears nowhere else on Wikipedia.  In an attempt to be thorough, the discussion of modes has become longer than ideal.  It is a pity there is not a good article that can be linked to.  I think the solution is to create a stub-plus article at Longitudinal-section mode with the current text and have a simpler summary here.  What do you think?  By the way, the transverse modes are not hybrid modes.  <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 15:04, 4 December 2018 (UTC)
 * Yes, I think that's a good idea. The notation and derivation aren't necessary here. Mike Christie (talk - contribs -  library) 02:47, 5 December 2018 (UTC)
 * Done. Hopefully, that's a lot clearer now.  I've also created mode (electromagnetism) to provide navigation around the zoo of mode types. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 16:58, 6 December 2018 (UTC)
 * Definitely an improvement. How about putting a main at the top of the Modes section, pointing to the new article? Mike Christie (talk - contribs -  library) 10:59, 7 December 2018 (UTC)
 * I wouldn't object if someone does that, but personally I feel a list+ navigation page doesn't amount to a main article. Really, there is more information right here on this page.  I would feel misled and my time had been wasted if I was directed to that as a main page. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 14:04, 7 December 2018 (UTC)

Continuing: -- More to come. Mike Christie (talk - contribs - library) 03:17, 5 December 2018 (UTC)
 * Other factors detracting from Q: "detract" is usually used for worth, not numerical value. How about "Other factors that reduce Q" or "that lower Q"?
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 19:08, 5 December 2018 (UTC)
 * The mixed media of air and dielectric leads, in theory, to...: "leads" sounds wrong to me, since "media" is plural. How about rephrasing: "Since the wave travels through both air and dielectric, the transmission mode is, in theory, not pure TEM, but a thin dielectric..."?
 * If this is just a grammatical issue, why not just change "leads" to "lead"? I like the phrase mixed media because it is imparting more general information to the reader than the specific case being discussed. That is, mixing high and low dielectric constant solid materials will also have this effect. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 19:08, 5 December 2018 (UTC)
 * That might work; I'll see if I can come with any better wording that preserves that phrase. Mike Christie (talk - contribs - library) 02:53, 6 December 2018 (UTC)
 * How about expanding this slightly to make the point clearer? "Since the wave is travelling through the mixed media of air and dielectric, the transmission mode, in theory, is not pure TEM, but a thin dielectric renders this effect negligible." Mike Christie (talk - contribs -  library) 11:25, 7 December 2018 (UTC)
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 14:13, 7 December 2018 (UTC)
 * The reduced permittivity results in larger printed components, which detracts from miniaturisation, but is easier to manufacture. The subjects of "detracts" and "is" are not the same; the size is what detracts, but the component is what is easier to manufacture. Suggest "The reduced permittivity results in larger printed components, which are harder to miniaturise, but easier to manufacture."  If "harder" is wrong because it's a limit, not a difficulty, then "The reduced permittivity results in larger printed components, which limits miniaturisation, but makes the components easier to manufacture".
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 19:08, 5 December 2018 (UTC)

More: -- That's it for a first pass. I'll think about the unstruck points above some more, and read through again once you've responded to these last points. Mike Christie (talk - contribs - library) 03:59, 6 December 2018 (UTC)
 * SIW also has high Q and high power handling. Additionally, as a planar technology, SIW is easier to integrate with other components. "Also" and "Additionally" do the same work here, so it might be better to combine the sentences: "SIW also has high Q and high power handling, and, as a planar technology, is easier to integrate with other components."
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 17:39, 6 December 2018 (UTC)
 * bilateral finline has lower loss for similar reasons to the advantages of bilateral suspended stripline: this isn't quite right; the advantages of BSS are not the reason for bilateral finline's lower loss. I'm not sure how to reword this without changing the meaning, but perhaps "bilateral finline has lower loss, as with bilateral suspended stripline, and for similar reasons".
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 17:39, 6 December 2018 (UTC)
 * radiation from bends and losses in the dielectric-metal adhesive severely detract from this figure: another instance of "detract" being not quite the right word. How about "losses in the dielectric-metal adhesive significantly reduce this figure" or "significantly lower the attainable Q".
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 17:39, 6 December 2018 (UTC)
 * However, imageline is not a suitable technology at lower frequencies. As far as I can tell this statement is not further explained; is there a concise reason that can be given?
 * No further explanation, because the source gives no further explanation. Clearly, it won't pass DC (because imageline is an insulator).  More profoundly, as the frequency goes lower and lower, the wavelength becomes larger and larger and the field is less and less actually contained within the imageline.  In the limit, it becomes no different from transmitting radio waves through the air, and the line is not really acting as a guide at all.  Do we need to give a reason? I'll see if anything can be sourced. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 17:39, 6 December 2018 (UTC)
 * Not required, just curious. I wouldn't withhold support, but I think it's a natural question for a reader to ask, so anything you can source would be good. Mike Christie (talk - contribs -  library) 10:56, 7 December 2018 (UTC)
 * Transitions between types using unbalanced conductive lines are straightforward enough: this is mostly just a matter of providing continuity... Three qualifiers in a short span: "enough", "mostly", and "just". I think you could cut "enough" and "just" without changing the meaning.
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 18:34, 6 December 2018 (UTC)
 * The development of planar technologies was driven at first by the needs of the US military, but today it can be found... "It" refers to "planar technologies", so it should be "they", or make it "planar technology", or "...but today circuits using planar transmission lines can be found..." or some similar construction.
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 18:34, 6 December 2018 (UTC)
 * Do we need to mention Thomas H. Lee in the text? Cutting that would make it easier to join the sentence with the next one, which would flow better: "Harold A. Wheeler may have experimented with coplanar lines as early as the 1930s, but the first documented planar transmission line was stripline, invented by Robert M. Barrett and published by Barrett and Barnes in 1951."  The next sentence starts with "Although", so it would be nice to eliminate that "However".  Similarly for "According to Barrett".  If you feel these are claims that are not strong enough to appear in the text without some qualification, could they be abbreviated to something like "Reportedly"?
 * I'm surprised you're suggesting "reportedly". That's an invitation for someone to slap a   tag on it.  I wouldn't like to omit the attribution to either claim, unless there are primary documents at the dates claimed from the alleged researchers themselves.  At the moment it's anecdote so has to be attributed. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 18:34, 6 December 2018 (UTC)
 * If it needs to be attributed that's fine. I don't think   tags are justified where the source clearly gives the attribution, and I remove those where I'm familiar with the source, but I agree some editors will tag that sort of construction. Mike Christie (talk - contribs -  library) 10:56, 7 December 2018 (UTC)
 * I've cut out four "however"s with my copyedits, but more could go -- there are still seventeen in the text. It's a useful word but it's easy to overuse, and I think you should cut some more.  Often it can simply be removed with little effect on the meaning.
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 19:08, 6 December 2018 (UTC)
 * Much improved. I think a couple more could go but this is fine. Mike Christie (talk - contribs -  library) 10:56, 7 December 2018 (UTC)
 * Suggest linking MMIC again at the end of the "History" section; the earlier link is far above and the acronym is unhelpful to a lay reader.
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 19:08, 6 December 2018 (UTC)

Support. There are a couple of minor points still being discussed above, but nothing that affects my support. Mike Christie (talk - contribs - library) 11:25, 7 December 2018 (UTC)

Jens Lallensack
Absolutely no idea about the topic, but I will try.
 * working at microwave frequencies – But the first sentence says "Planar transmission lines are transmission lines", and the linked article transmission lines states that they are at radio frequencies.
 * Hi Jens, thanks for reviewing. Microwaves are considered a subset of radio frequencies. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 12:47, 25 December 2018 (UTC)
 * normal simple interconnections – what precisely is meant by this? Is there an article to link this to?
 * There is no special technical meaning here; it is just normal English. It means like the wires connecting your loudspeakers to your hifi amplifier.  This came up at peer review as well and the next sentence (With normal interconnections the propagation...) is intended to clarify the issue.  I'm not sure how to make this any clearer.  Any suggestions are welcome. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 12:47, 25 December 2018 (UTC)
 * OK, but still, a link would help. These "normal interconnections" appear to be the most basic type; they really have no Wikipedia article? What about Electrical cable? --Jens Lallensack (talk) 08:19, 26 December 2018 (UTC)
 * Good idea - done. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 12:49, 26 December 2018 (UTC)
 * Transmission lines are more than normal simple interconnections. With normal interconnections the propagation of the electromagnetic wave along the wire is fast enough to be considered instantaneous – You are comparing transmission lines with normal interconnections. But it seems you are rather comparing different wave length to wire length ratios? Its unclear to me. The problem might be that I don't understand what a normal interconnection is.
 * Yes, you are right that when using shorter wavelengths on the same piece of wire it will suddenly exhibit transmission line effects where there were none before, but it is still valid to treat them separately. With a normal interconnection, we don't worry too much about the geometry.  As soon as we start considering the connection to be a transmission line, steps are taken to ensure the cross-sectional geometry is constant and well defined along the entire length of the line. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 12:47, 25 December 2018 (UTC)
 * Ok, understood, why not adding this to the lead (I mean, the requirement that cross-sectional geometry is constant)? Because right now, the first paragraph of the lead starts with Transmission lines are more than normal simple interconnections but never explains what the difference is between the two. --Jens Lallensack (talk) 08:19, 26 December 2018 (UTC)
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 13:23, 26 December 2018 (UTC)
 * Other planar types, such as slotline, finline, and imageline, transmit along a strip of dielectric, – can you link these different types, and also "planar types"?
 * This article is the best source of information on Wikipedia for all those types. I've linked them in the lead, but they all redirect back here.  There is only passing mentions of slotline elsewhere on Wikipedia and nothing at all for imageline.  For finline there is finline filter, but that's only a paragraph in another article and there is more information here on the line itself. "Planar types" is the whole of this article. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 22:18, 25 December 2018 (UTC)
 * I didn't get that these are planar transmission lines as well, instead I thought "planar types" are some higher-ranking category that contains planar transmission lines, amongst others. So if one talks about "planar types", these are always planar transmission lines? Maybe write, for clarity, "other types of planar transmission lines"? --Jens Lallensack (talk) 08:19, 26 December 2018 (UTC)
 * Done. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 13:23, 26 December 2018 (UTC)
 * I did not fully understand the lead, even with consulting the linked articles. What I got is that planar transmission lines always have two conductors, which for some reasons is better at microwave frequencies. But in the first article section "General properties", this is not even mentioned. The lead compares with "other planar types", "Lumped passive components", and "other types, such as coaxial cable", but without guiding the reader where to place this info. Maybe a reorganization of the lead is needed; maybe explaining point by point with a clear red threat and keeping it simple is better. I'm a bit at a loss. --Jens Lallensack (talk) 10:10, 25 December 2018 (UTC)
 * I'm not sure there is anything actionable there. The lead does not say planar transmission lines always have two conductors.  It does say that the four main types have a pair of conductors.  There is nothing unusual in this – that is the normal number for an electrical circuit.  The reason planar is preferred is stated in the second sentence of the lead "...planar type fits in well with the manufacturing methods..." and is expanded on in the General properties section "The principal advantage of the planar types is that they can be manufactured using the same processes used to make..."  For "other planar types" these are all now linked, see comment above. "Lumped components" is linked to lumped element model and coaxial line is linked to coaxial cable. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 22:52, 25 December 2018 (UTC)
 * I understand it now, it was mainly resulting from my confusion (see one point above). --Jens Lallensack (talk) 08:19, 26 December 2018 (UTC)

Coordinator note: do you have any more to add here? We are struggling slightly for reviews here, but I'm inclined to leave this a little longer as it's a very technical article, and those always struggle to attract reviewers. I'll add it to the urgent list and see if that helps. Sarastro (talk) 22:29, 13 January 2019 (UTC)
 * I can't spot additional problems, but I must confess that I really lack the expertise here to be able to appropriately assess the article. I give my support, but please note that this cannot be counted as a full review, which I am unable to deliver. --Jens Lallensack (talk) 18:25, 14 January 2019 (UTC)
 * Note that technically minded editors were involved in the peer review (one of them with experience in exactly this field). Sadly, neither of them seem inclined to take part here, although I have pinged them.  However, I am confident that any serious technical boo-boos would have already been picked up. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 20:15, 14 January 2019 (UTC)
 * Well, I see no harm in pinging them here. The only two editors I see on the PR are and . Do either of you have anything to add here? What we are really looking for is an indication that this article is accurate and represents the subject comprehensively. Even if you don't comment on anything else, it would be a huge help if you could comment on this. Sarastro (talk) 23:24, 17 January 2019 (UTC)
 * I received your ping and will take a look. I hope to have comments by sometime tomorrow. -- 00:24, 18 January 2019 (UTC)
 * I have been been remiss in not reviewing this article - I will endeavour to do better. Considering the ubiquity of wireless technology today, and its heavy dependence on planar transmission lines, this strikes me as an important article (even if it does not meet project criteria for 'high importance'). catslash (talk) 16:00, 18 January 2019 (UTC)
 * Just to clarify that, the article is currently unassessed by either of the wikiprojects to which it has been put in scope. It has not been assessed as low importance. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 18:21, 18 January 2019 (UTC)

Comments by Mark viking
I looked at this article during a peer review and I must say that both the lead and lead illustration caption are much improved in terms of clarity of the writing and a more accessible prose style. The new lead illustration also addresses my earlier criticisms. Nicely done.

I have read through the article and it looks well written and covers much of the subject well. Below are some comments and questions. Fair warning: I am not an FA guru, so if some requests are nonstandard, that might be me not knowing the FA culture.
 * 1) I think an FA-class article should have its own short description, rather than relying on the default Wikidata entry. Best to add one.
 * 2) * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 13:41, 18 January 2019 (UTC)
 * 3) In the lead, slotline, finline, and imageline links look like (self) redirects. Would it be best to format them as section links?
 * 4) * I don't have any very strong feelings on this, but I did it with redirects rather than section links because at least some of them, if not all, are potentially standalone articles in the future. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 13:41, 18 January 2019 (UTC)
 * 5) In the area of completeness, how do quasiplanar transmission lines compare to planar transmission lines? Perhaps they should be mentioned.
 * 6) * What exactly did you have in mind? The term quasi-planar appears in several contexts. A planar structure existing within a non-planar structure is described as quasi-planar.  The principle example of this is finline which is already covered.  I'll add the term to that section.  I've also heard bilateral forms called quasi-planar, also already covered, but in my opinion that is being unnecessarily pedantic and would just add confusion to the article. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 14:31, 18 January 2019 (UTC)
 * 7) A real strength of this article is a detailed summary of all the different geometry and material types and the salient properties of these devices. But there is little in the article on applications of these devices. What are they used for? Why all the different types--there must be different application areas for this variety to coexist. For example, slotlines can be used as antennas, but finlines would be inappropriate as antennas. Perhaps a table or short section giving typical uses for the different types would allow for users to better understand why there is such a variety of different types.
 * 8) * If you are looking for circuit function versus line type, I don't think that is really a thing. In general, all formats can support all circuit blocks.  The main things driving choice of technology are ease of manufacture, frequency of operation, and to some extent range of realisable impedances and Q.  Ease of manufacture favours microstrip, and sometimes coplanar, which I'm pretty sure is already highlighted prominently.  The rest is summarised in the table of major characteristics. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 13:41, 18 January 2019 (UTC)
 * 9) In the area of completeness, there is nothing in the article on how these devices are designed. I get the idea that unlike components like capacitors and resistors, many planar devices are custom-designed according to the application. One cannot go into a lot of detail on design and modeling and remain accessible, but summarizing the main or typical methods used would be a good addition. Are there dominant software packages people use? Do people use analytic/conformal techniques? Do folks do their own EM simulations? Or is a practical, best practices approach typically used, with standard designs and standard formulas in a handbook somewhere?
 * 10) * Design of circuits is within the scope of distributed element circuit (which is largely about planar forms). Specific circuit blocks can be found in distributed element filter and power dividers and directional couplers (which also concentrate on planar forms).  Articles also exist for individual circuits.  If all these pages did not exist there might be a case for further expansion, but as they do, this page needs to stay focused on its topic, the lines themselves.  There is, of course, some discussion of circuits  to put the subject into context, but a big expansion would be going off topic. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 13:41, 18 January 2019 (UTC)

Overall the article looks very good and the content already present looks accurate as far as I can tell. I cannot see anything else that might need polishing. -- 05:18, 18 January 2019 (UTC)

Comments from Catslash
Having achieved Good Article status and additionally undergone peer-review, any short-comings this article may had, have for the most part been rectified. Nevertheless, here are a few new observations (more to follow):


 * 1) The lede struggles for want of a term for a non-transmission-line.  There is a danger that simple and normal could be mistaken for technical terms, and normal is in any case context-dependent (hence NFN).  Perhaps Transmission lines are more than simply interconnections for the first instance?  The following sentence seems harder to fix though.
 * Done on your rewording (although I hope we are not starting to go in circles with this sentence with contradictory suggestions from consecutive reviewers). I've also changed "normal" in the following sentence.  That seems to be the word that is causing all the confusion.  I don't think "want of a term for a non-transmission-line" is going to be actionable unless you can suggest a term based on RS. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 19:04, 21 January 2019 (UTC)
 * Sorry, my comment was unclear; I meant to say that we should not be inventing a term for this. It is clearer and less awkward now. catslash (talk) 23:53, 22 January 2019 (UTC)
 * 1) In the (rather nice) new mode diagrams, the microstip ground plane is unclear, being darker and thinner than the  other metallization.  As the microstip ground plane is not mentioned in the discussion of the modes, it is not essential to distinguish it in the diagram, and it may be better to depict the metallization consistently throughout the diagram.
 * I don't want to change the colours because that colour key has been used throughout the article in all the diagrams. I would also point out that the two layers can really be different colours like this circuit with gold-plated lines.  Would making the ground plane thicker and more visible be helpful?  The thicknesses aren't really to scale anyway. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 17:29, 21 January 2019 (UTC)
 * Yes, making the ground thicker than to-scale would help. On a small screen, the ground-plane is easily overlooked at present, especially as both the substrate and the ground can appear fairly dark (depending on the display settings).  I did notice that the dark brown is used for the enclosure/box in some of the diagrams (such as the suspended stripline). catslash (talk) 23:53, 22 January 2019 (UTC)
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 00:23, 23 January 2019 (UTC)
 * 1) From the lede:  A pattern of transmission lines ... simply by applying patterns to the existing substrate.  Perhaps it would be good at this point to refer to the lede picture which illustrates this very nicely (or perhaps you consider the lede to be long enough already). catslash (talk) 00:10, 23 January 2019 (UTC)
 * I don't object to that, but couldn't think of a nice form of words. The caption says it all anyway. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 00:38, 25 January 2019 (UTC)
 * You are right; the caption says it.
 * catslash (talk) 19:30, 20 January 2019 (UTC)


 * Support FA status. Having re-read the article and made as few minor tweaks, I can find no fault.  The FA criteria appear to be all satisfied.  I have not checked the copyright status of the illustrations, but there is no reason to suspect any problem there. catslash (talk) 00:29, 27 January 2019 (UTC)

Jo-Jo
Jo-Jo Eumerus (talk, contributions) 07:05, 21 January 2019 (UTC)
 * Are "Radio TV News" a "New Age International" (there is apparently a similarly named diploma mill), "Morgan & Claypool" and "PHI Learning" good publishers?
 * "Radio TV News". This has not been cited in the article to verify any facts. It is in the bibliography as a primary source for Barrett's work.  It is so cited by several RS.
 * "New Age International" are an Indian publisher of technical books. As far as I can tell, they are not associated with New Age International University which has an Italian address.  As far as I can tell, they are not a vanity press.  SENSE, while not putting them in its top (refereed) ranks, still ranks their output as professional publications for an academic audience.  One of the authors of the book in question is a recipient of the Om Prakash Bhasin Award.  My personal assessment of the book is that it seems thorough and professional.
 * "Morgan & Claypool" are a digital publisher aimed at an R&D audience. I am not seeing any sign that they are a vanity press. They  seem to be respected by the University of California's California Digital Library, and by the IEEE
 * "PHI Learning" is an Indian publisher aiming mostly at a student audience. They have been in business since 1963 and there is no sign that they are a vanity press.  I've no idea why you even think they are suspect unless it is just because they are Indian.  In any case, the phenomenon they are cited for is very well known to those skilled in the art, and really wouldn't need a reference at all anywhere other than Wikipedia.
 * <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 00:21, 22 January 2019 (UTC), 04:42, 22 January 2019 (UTC) and 16:08, 22 January 2019 (UTC)
 * I generally call out sources when I can't find any obvious indication they are good sources. Looking for this "PHL Learning" thing didn't give me any clear indication of its reliability, hence the question. Jo-Jo Eumerus (talk, contributions) 16:51, 22 January 2019 (UTC)
 * Lead section seems readable enough to me, maybe that subcomment at its end should be put in a footnote like efn.
 * The comment at the end is part of the definition of the scope of the article, so I don't think it should be relegated to a footnote. Manual of Style/Lead section explicitly requires such minutiae of details of scope to be placed at the end of the lead. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 00:11, 22 January 2019 (UTC)
 * I am wondering if there is history of the planar transmission line more recent than 1976.
 * Remarkably, all the major types were described quite some time ago. There may be some minor variants that are more recent, but we don't need that level of detail in an overview article.  I did notice, however, that image line is missing from the history section.  I'll add something shortly, but that dates back to the 1950s so won't affect the 1976 end.  There have certainly been more recent developments in circuit applications, perhaps the most recent field is fractal antennae and filters, but that belongs in another article (distributed element circuit). <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 19:20, 21 January 2019 (UTC)
 * Folded waveguides, e.g., SIFW, seem like a 21st century development. -- 02:02, 22 January 2019 (UTC)
 * It's definitely not that recent, but you may be right that it's later than 1976. Of the sources we already have in the article, Wu and Kishk say it is recent without giving an actual date or name.  The first description of it may have been this 1998 paper, but I haven't got a source that directly says so. Still looking. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 23:06, 22 January 2019 (UTC)
 * ok, I've put something in on SIW. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 00:09, 23 January 2019 (UTC)
 * Took a gander at prose and images, it mostly seems OK to me although I didn't check that deeply. Jo-Jo Eumerus (talk, contributions) 07:20, 25 January 2019 (UTC)

SN
I made some minor grammar tweaks here. Could the lead image be expanded slightly? Image use elsewhere is excellent and your referencing perfect. —— SerialNumber  54129  16:55, 22 January 2019 (UTC)
 * Done <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 00:09, 23 January 2019 (UTC)

Coordinator comment: I'd like to get this wrapped up fairly soon if we can. We have much more commentary now, just pinging those who have reviewed (,, and ) to see if they think any more needs doing. For the benefit of those new to FAC, if you believe that the article meets the FA criteria, you can indicate that you support (or oppose if you don't think it meets those criteria). If you don't feel able to comment on all the criteria, and maybe just wanted to indicate that it met for example, 1b or 1c (comprehensive and well researched), that is perfectly acceptable. Sarastro (talk) 22:54, 24 January 2019 (UTC)
 * I Support this candidature. It clearly fulfills the criteria, and my few concerns have been addressed. 23:08, 24 January 2019 (UTC) — Preceding unsigned comment added by Serial Number 54129 (talk • contribs)

Tim riley
The subject is so far out of my ken that I am uneasy about pontificating, but, with the exception that the Engelmann source is misspelled as Englemann, everything in this article looks authoritative to me. I don't go so far as to claim I understood it all, but I found no examples of gratuitous jargon, and the prose is very readable, which can't be easy in such a technical subject. So, with the caveat that I am the layest of laymen, I support the promotion of this article. It is handsomely illustrated and widely sourced (though I see the main author is evidently on a one-person campaign against 13-digit ISBNs). Another feather in Wikipedia's cap.  Tim riley  talk   15:12, 27 January 2019 (UTC)
 * I've corrected the misspelling. I didn't realise that 13-digit ISBNs was an issue.  Is there a guideline somewhere on how to convert them, circumstances they should not be converted etc? <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 15:23, 27 January 2019 (UTC)
 * There's no requirement to use 13-digit ISBNs, but per WP:ISBN they are preferred if they're available. I use them when I see them on the source. Mike Christie (talk - contribs -  library) 15:28, 27 January 2019 (UTC)
 * 13-digit ISBNs are lumpen things with not a breath of poetry about them, but like Mike Christie I duly follow WP:ISBN when possible. I didn't mean to imply that you should change the 10-digit ones here.  Tim riley  talk   16:06, 27 January 2019 (UTC)

Coordinator comment: I think we're almost ready to wrap this up now and I think we have covered all the bases we need to. All that's left is a formal source review. Maybe, or  could oblige? Sarastro (talk) 22:18, 30 January 2019 (UTC)
 * I did a source review at the GA, here; formatting is fine. Jo-Jo Eumerus looked at reliability above.  This would be SpinningSpark's fifth FA; their last successful FAC was about five years ago -- I don't know if a spotcheck is required but I wouldn't be able to do one as I don't have access to the sources. Mike Christie (talk - contribs -  library) 23:02, 30 January 2019 (UTC)

Comments from Dweller

 * Is there a typo in "With transmissions lines" in the lead? --Dweller (talk) Become old fashioned! 22:35, 4 February 2019 (UTC)
 * There was. Fixed. catslash (talk) 22:55, 4 February 2019 (UTC)


 * Robert Barrett, the inventor. The claim that he invented them isn't referenced, and also you tell us nothing about who he was, which is a surprising omission. --Dweller (talk) Become old fashioned! 22:41, 4 February 2019 (UTC)
 * It is cited. The relevant paragraph in the history is cited to three sources.  All three verify Barrett's priority,
 * You need to cite important claims more carefully. This should be cited immediately after the claim. --Dweller (talk) Become old fashioned! 12:32, 6 February 2019 (UTC)
 * Bhat & Koul, "The first planar transmission line, called the 'strip transmission line', was proposed by Barrett and Barnes as early as 1951."
 * Oliner, "The inventor of the stripline concept was Robert M. Barrett of the Air Force Cambridge Research Center."
 * Lee, "In 1951, Robert M. Barrett proposed the realization of planar versions of many classical microwave components using PC board fabrication methods."
 * The lack of bio details is merely following the pattern in the rest of the article, just giving the names and referencing the primary papers and leaving it to more focused articles to give more details. In any case, I don't think there is much available about Barrett in sources – he doesn't have an article. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 23:39, 4 February 2019 (UTC)
 * Here's a gift . Barrett isn't just another one of many people in the article, he's the inventor and deserves some special treatment in an encyclopedia article, rather than a technical manual. --Dweller (talk) Become old fashioned! 12:38, 6 February 2019 (UTC)
 * Done. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 10:14, 7 February 2019 (UTC)


 * The asterisk after coplanar waveguide is unfortunately unhelpful. I looked at the bottom of the text for the rubric and saw none. It's very odd to have it where it is. Why not use a clickable lettered footnote, like in [] --Dweller (talk) Become old fashioned! 22:43, 4 February 2019 (UTC)
 * See my reply to the same comment above. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 23:47, 4 February 2019 (UTC)
 * I couldn't disagree more strongly. The MOS text you refer to is talking about text in the lead, not some kind of hidden non footnotey footnote. We have an obligation to make things easy for our readers. --Dweller (talk) Become old fashioned! 12:39, 6 February 2019 (UTC)
 * Ok, I've reformatted it as normal text. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 09:57, 7 February 2019 (UTC)

Smashing. Support --Dweller (talk) Become old fashioned! 10:34, 7 February 2019 (UTC)


 * Support. I made a couple of very minor tweaks, including to a ref or two. I see has asked for a formal source review, and I looked over this aspect with special care. Like  I found this passes on the formatting side of things. I also cannot make spot checks or consider whether it covers every possible source that covers the subject, but I'm going to AGF that it does. Cheers - SchroCat (talk) 11:57, 12 February 2019 (UTC)
 * I've undone your removal of links in the lead. These links were requested by another reviewer above.  The redirects go to a specific section in the article.  They could be made direct section links, but they are potentially stand-alone articles so it is better done as a bookmark redirect. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 13:05, 12 February 2019 (UTC)
 * No, they should be done with the hashtag to direct it to the right place (per WP:SELFRED). If stand-alone articles are later created, then the links can be tweaked. If they are suitable for stand-alone articles, then it would be worth setting up stubs as starters to have the info there. - SchroCat (talk) 13:19, 12 February 2019 (UTC)
 * SELFRED explicitly says these kind of selfrefs are acceptable. I should have marked them with R to section, which I will do shortly.  The problem with doing it your way is that the person creating the article does not necessarily know that this article has embedded section links. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 13:32, 12 February 2019 (UTC)
 * I've struck my support. If these terms deserve an article, give them one, but if you just revert a couple of times without fully discussing with the reviewers who are trying to help you, isn't ideal. - SchroCat (talk) 13:42, 12 February 2019 (UTC)
 * My last revert was because the links you had inserted were actually broken, so one way or another they would bave had to go anyway. Making an FA dependent on creating another article is a ridiculous position. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 13:56, 12 February 2019 (UTC)
 * "Making an FA dependent on creating another article is a ridiculous position": that is not what I have said, obviously. - SchroCat (talk) 14:04, 12 February 2019 (UTC)

Closing comment: I think we have had a good range of reviews, both technical and from an "ordinary reader" viewpoint; there is no benefit leaving this open any longer as there is a clear consensus to promote. I note the disagreement in SchroCat's review above, but as he has not opposed and the issue seems relatively minor, there is no reason to delay further. The duplinks may need to be checked as we seem to have quite a few; I can see the benefit of having some in an article as technical as this, but I'd appreciate the main editors just looking to see if any are not needed (I removed one that was duplicated in the lead). This tool will highlight any duplication. Finally, I note that it has been some time since the nominator's last FAC. I think we are OK for this article, but if I could ask that one be done for your next nomination, and we can set something in motion much earlier in the process! Sarastro (talk) 23:07, 13 February 2019 (UTC)

Sarastro (talk) 23:07, 13 February 2019 (UTC)
 * The above discussion is preserved as an archive. Please do not modify it. No further edits should be made to this page.