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The question in particular that led me to post here is this question which has been closed by the community with the stated reason of being off topic: How important is the plastic coating around a coax?

While this is indeed a question that would be entirely on-topic for the Electrical Engineering Stack Exchange, antennae and RF gear are also a rather mystifying thing to most drone owners, the majority of which are not electrical engineers (while even some people who do build their own circuits from scratch are sometimes mystified by the behavior of high-frequency electronics).

Such users probably need an answer that is both worded in simple terms that do not require any EE background, and immediately applicable to the task at hand. i.e, in this case, something like "The coating is almost entirely irrelevant (but you should probably heatshrink it to keep moisture out), but the metallic shielding is very relevant, and you've got it damaged as well. Resolder it to the connector, or you might burn your VTX", as opposed to delving into all the details on the role of the dielectric in coax cable, how it affects propagation, impedance and signal loss in the feedline, etc etc as would be typical of EE.SE, and which would confuse a drone owner even more (not that you can't write all that in an answer here, but please keep it understandable and connected with the practical considerations of dronebuilding).

I feel that questions related to drone electronics, including RF equipment, are one of the hardest of those that arise while building and using FPV aircraft, yet also one of the most commonly encountered. At the same time I think that there is no other place on SE that would be able to consistently provide this kind of "FPV-tailored" answers to those genuinely complicated questions, so we should strive to be the community that can answer them, and such questions should be on-topic here.

I would like to invite discussion on the matter below and will be glad to hear all opinions.

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I'm of the opinion that we should include questions that anybody building or maintaining drones would need to know, partly because much of the kit available, especially leading edge developments in flight controllers, has little or no documentation, so new enthusiasts often have questions in this area.

I agree, avoid underlying maths or physics unless we absolutely need it to explain something, but your coax example seems like it really should be on topic here. It doesn't require complex theory or maths to describe what the plastic is for and make recommendations.

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Fully on topic, but the reply quality is going to be extremely variable. There are cases where I can provide extremely EE themed answers, but with context that makes them relevant to this specific application set... Without clear moderation guides on how to manage responses that are... not inaccurate or unhelpful, but don't actually usefully address the root question being asked, this is going to be a bit trickier.

Generally, I'd be for allow, and let the natural course of downvotes drift these off the the side, unless a particularly good answer is in there and justifies keeping it around, but slow quiet putting out to pasture is fine.

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Yes, although we must be careful to separate drone building from simple maintenance tasks.

How much does mounting an antenna near a carbon fiber frame degrade signal reception? is an excellent example of drone building. Antenna questions in fixed-wing have very different responses from in multirotors, and both are far from experiences in other domains. An RF expert might give a completely wrong answer because s/he is unfamiliar with certain critical aspects of drones.

What are the exact specifications of a RushFPV SMA connector? is another excellent example. It asks a question about a product which is only in the drones domain, and the answer is canonical and can serve as the google answer to anyone ever asking this question in the future.

Contrast that to How important is the plastic coating around a coax?, where the answer is always "it depends" and the only link the question has to drones is that the questioner has a drone. These kind of posts drop the signal to noise ratio and should be discouraged.

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    $\begingroup$ I must disagree with you in the judgement that an RF expert will answer a drone-related antenna question incorrectly – besides possibly suggesting an, e.g., mounting strategy that would be perfect from an RF perspective but impractical for other reasons (which would not be a "completely wrong" answer and would still contribute to the discussion). They might, however, explain it in terms illegible to the average drone builder. $\endgroup$
    – FlashCactus
    Apr 16, 2020 at 12:02
  • $\begingroup$ It's not that they'll answer it incorrectly. It's that they won't be here to answer it all, because they'll see the quality of the questions and head elsewhere. Put yourself in their shoes. They see a question being asked where the answer is "it's not plugged it". How much tolerance would we have for a site full of people asking why their drones don't fly, and they show a picture of a drone with the props missing? SE is a great place for answering a question once and having it stay answered. $\endgroup$
    – Kenn Sebesta
    Apr 16, 2020 at 12:07
  • $\begingroup$ As for the coax question, in this case the answer is very clear-cut. It's not "it depends". While it is indeed in itself very generic, it's also very relevant to drones despite that; Just as relevant as questions along the lines of "what is circular polarization", which is very general, but significant for the hobby or "what would happen if a VTX is turned on without an antenna", which is relevant anywhere involving a radio transmitter and only related to drones in that there is one in them. $\endgroup$
    – FlashCactus
    Apr 16, 2020 at 12:14
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    $\begingroup$ I agree that most of the questions encountered in the first day of this site's life are very basic and might not be super interesting to specialists in the field, but as you said, SE is a great place for answering a question once and having it stay answered. The moment such a question is answered, it will stay answered forever and forever be part of the extensive knowledgebase that this SE will hopefully be one day, laying the foundation for more complex future questions in the process. Because of that, at this stage I'd lean towards valuing good generic questions over very specific ones. $\endgroup$
    – FlashCactus
    Apr 16, 2020 at 12:17
  • $\begingroup$ I'm not sure how "you forgot to plug it in, ya dummy" is a helpful question or answer. The specific questions other question you mention are much more in line with the site. They have drone-specific qualities. $\endgroup$
    – Kenn Sebesta
    Apr 16, 2020 at 12:24
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    $\begingroup$ What leads you to believe that the phrase you just wrote is (or was) going to be an answer to any of the questions mentioned? (In fact, I would consider most of the numerous "my drone is flipping out after assembly, what's wrong with it" questions that are cropping up on this site more in line with that phrase.) As for the second part, how is a question about connecting (or not) an antenna to a VTX pigtail more drone-specific than a question about whether a damaged VTX pigtail is okay (or not)? What drone-specific qualities does the first question have that the second doesn't? $\endgroup$
    – FlashCactus
    Apr 16, 2020 at 12:33
  • $\begingroup$ That said, we might want to encourage/enforce more indication of prior research by the asker in order to cut down on the lazy kind of questions which can be answered by the first link in google. $\endgroup$
    – FlashCactus
    Apr 16, 2020 at 12:38
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    $\begingroup$ Having been a moderator on a number of sites from very early on through to graduation, experience suggests that while we do want to keep quality high (ie no "plug it in" posts etc) we should not tighten scope too much early on. It's easier to keep it broader until we grow, and then see if there are areas the community wants to rule out of scope. $\endgroup$
    – Rory Alsop
    Apr 16, 2020 at 12:44
  • $\begingroup$ In drones.stackexchange.com/questions/251/… the metal connection is physically broken. It's what's "not plugged in". The following discussion won't be "la reference" which google lists as the top post to a query, and so that's what hints to me that it's not appropriate. It's a good question, as someone who doesn't know RF can learn tons from the answer. It's just not relevant here. $\endgroup$
    – Kenn Sebesta
    Apr 16, 2020 at 12:46
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    $\begingroup$ @RoryAlsop interesting, and spoken from internal SE experience. This somewhat contradicts my personal experience outside SE, which is that if community curation doesn't occur right away, it's easy for it to drift in a self-reinforcing spiral. Thanks for the lucid counterpoint. $\endgroup$
    – Kenn Sebesta
    Apr 16, 2020 at 12:48
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    $\begingroup$ The good thing here is that the SE framework (mods and CMs and guidelines) do provide a sensible start point. Once the community is strong enough to do most of the moderation, and mods really become exception handlers, that's a good point to look at maturing scope - usually through discussions in meta and chat $\endgroup$
    – Rory Alsop
    Apr 16, 2020 at 12:50
  • $\begingroup$ Again, coming from the philosophical general systems theory mindset, lateral domain integration is so fundamentally requisite to understanding the overall tradespace in which any design is intended to operate, I'm okay with having lots of information that is in closely tied relevant fields, if not strictly dead-center on topic, because we implicitly have to expect users and contributors to filter already for what is quality responses to relevant topics... and letting that happen organically is the more sustainable answer. $\endgroup$
    – Tehllama
    May 5, 2020 at 14:06

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