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There's a significant amount of questions¹ of the type:

Here's a {LED driver|amplifier|inverter|…} circuit I found on some website, explain how it works, or why we need {component}?

Problems with that are that

  1. getting answers here (because most of us are very enthusiastic about explaining practical simple circuits) inhibits OP's own research efforts, and
  2. many of these circuits are especially low-quality from an electronics point of view:
    • I've seen many circuits that are supposed to be "high-gain, low noise RF amplifiers", but are obviously copied from a website that copied them from another website, that copied them from an amateur radio mag, which copied them from another mag, which copied the circuit from someone who designed a basic Germanium semiconductor circuit without in-depth understanding of how these work in the 1950s
    • I've also seen numerous dangerous inverter circuits (things supposedly designed as resonant inverters, but where, probably through partial copy, the info on how to pick values and what not to supply with these, alongside with a total disregard for security measures), and most prominently
    • hundreds of 555-related questions that just are copies of basic 555 circuits where OP would simply need to research what the individual component values do to answer their own question (but can't, because the website they got the circuit from doesn't explain, but just display the circuit).
    • Also: the occasional total bullshack circuits sold by dubious vendors.
  3. They often don't even link to the original source, which makes constructive feedback even harder.

Now, I consider these to be questions of especially low quality for the following reasons:

  • they are all based on a lack of research – I know that for a beginner that is enthusiastic about building something that does something for the first time, it'll be hard to even find the appropriate ressources, but I really can't see why we're the ones to link to the same pages every day
  • they might benefit future readers in the same situation, but most of them really are duplicates, and again, spotting the duplicate from a couple questions that come up in a search for the keywords in OP's question would qualify as the minimum research
  • we're basically helping the proliferation and usage of badly-explained and badly-designed and outdated circuitry. I personally think we shouldn't.

So, of course, I can downvote such a question (which I think is the common thing we do for "bad question, do some research"), but I'd rather have a clear help page/rule entry that points out why exactly people shouldn't ask these.

Now: How do we want to approach such questions?

  • Only downvote, close as "unclear" if appropriate?
  • Only downvote, tend to close as "too broad", because an answer would basically mean explaining the basics of the type of circuit in question?
  • Have a separate close reason "Don't ask questions about circuits copied from a source that doesn't explain them without in-depth understanding of the topic"?

I'm slightly leaning towards the third option, as it's the clearest.


¹ citation might be needed, but really: I do think we agree it's a common phenomenon

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    \$\begingroup\$ We need to be careful to distinguish the "do the research for me" questions from the "I think I understand everything but Q6" questions. If they ask for a whole circuit explanation, I usually VTC "too broad" since you could really waffle more than fits into the 30k answer limit about any any nontrivial circuit. \$\endgroup\$ – PlasmaHH Jun 19 '17 at 9:06
  • \$\begingroup\$ good point, @PlasmaHH! So, maybe even better would be a VTC with basically a modified version of the "repair questions require understanding and specificity"; that way we'd only need to slightly modify that close reason, and still get a specific reason to close \$\endgroup\$ – Marcus Müller Jun 19 '17 at 9:12
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    \$\begingroup\$ This is not on our own meta, but it's related: Occasionally there are questions asked that seek to explain some soundbite of thing someone said or wrote. \$\endgroup\$ – Nick Alexeev Jun 19 '17 at 20:42
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    \$\begingroup\$ Related: Are modifying electronic questions on topic?. We'll answer focused questions when we have a fairly clear idea of how much the OP already understands. Anything else is "too broad". \$\endgroup\$ – Dave Tweed Jun 20 '17 at 11:44
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I think we already have the tools to handle these questions. As with any broad class of questions, there is quite a range from How do I increase the gain of this amplifier:

To What's the purpose of C2 in this audio amplifier:

The first is just random garbage thrown at us, whereas the second is a legitimate question with good opportunity to teach some electronics in the answers.

The first needs to be closed for the nearest handy reason (I'd probably pick too broad, but it really doesn't matter) and downvoted because the OP clearly didn't do any research at all, and just copied some mess he found in a dark corner of the internet somewhere.

So as with all these things, the answer is it depends, and it's a judgement call each time. It's hard to come up with a clear rule, but I'll know it when I see it.

Broadly, we don't want whole circuits the OP doesn't understand dumped on us. However, explaining details of how a circuit works, what it does, why particular components were chosen, what the criteria for choosing the components are, etc, can be good questions.

Of course no matter what else, these question need to be written with a little care, no sloppiness, and the schematics must also be neat, readable, and follow common conventions.

When the first thing I see is a wiring diagram instead of a schematic, I downvote on principle, refuse to read the text, then vote to close as unclear since without reading the text I don't know what is being asked. The same holds true for anything else that makes a question annoying to read and is just wasting the time of the volunteers here.

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    \$\begingroup\$ +1 for the first schematic. \$\endgroup\$ – Nick Alexeev Jun 19 '17 at 21:21
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    \$\begingroup\$ @NickAlexeev Slap that and instructables.com on a t-shirt and we've got a product. \$\endgroup\$ – Matt Young Jun 19 '17 at 23:21
  • \$\begingroup\$ @MattYoung aside from them probably not being happy about our abuse of their logo/domain, I'd totally get two of these shirts. \$\endgroup\$ – Marcus Müller Jun 20 '17 at 7:39
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    \$\begingroup\$ Olin, you made one minor mistake with the "bad question"'s circuit: "How do I increase the gain" requires an understanding of what gain is and what an amplifier does. The correct question would of course have been "PLS ANSWER ASAP: How do I make more output with this amplifier? (URGENT! HOMEWORK TOMORROW)" \$\endgroup\$ – Marcus Müller Jun 20 '17 at 7:40
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    \$\begingroup\$ "How do I kill myself with this Russian suicide circuit I bought on eBay?" \$\endgroup\$ – uzumaki Jun 25 '17 at 20:51
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    \$\begingroup\$ Olin, are you really saying you flat out vote to close posts without even reading them, just because you see a wiring diagram instead of a schematic? "I downvote on principle, refuse to read the text, then vote to close as unclear since without reading I don't know what is being asked" - Doesn't that sound like abusive behavior for SE? Can you elaborate? \$\endgroup\$ – schizoid04 Jun 26 '17 at 6:50
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    \$\begingroup\$ @schizoid04 a close vote is, in fact, reversible; I do consider transforming one's wiring diagram into the more abstract, yet easier to understand (and thus, more powerful) shape of a schematic the bare minimum we need to expect. Either the wiring diagram contains no necessary info related to the question, or it does but then should be converted to a schematic. Although his measures are extreme, I therefore agree with Olin on the fact that fritzing/wiring diagrams aren't suitable for anything, and must be transformed to schematics by OP first. There's enough users that straight up refuse,… \$\endgroup\$ – Marcus Müller Jun 26 '17 at 10:00
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    \$\begingroup\$ … to do that after being asked to do so, and I think Olin's harsh attitude at least partially stems from the fact that you really don't want to establish a site where it's "normal" to post wiring diagrams and expect answers (so, not a single one should pass, unless the question is about the transformation between wiring and schematic diagram). Problem here is that aside from being terrible to read, they are "recipes" rather than "blueprints", and many a user's problem simply stems from the fact that they forgot a wire etc, because they never even tried to figure out what their circuit does, … \$\endgroup\$ – Marcus Müller Jun 26 '17 at 10:01
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    \$\begingroup\$ … which they found in the shape of a wiring diagram somewhere. Now, trying to understand what you're doing is the first mental step you need to take when trying to get help with something, so, again, there's simply no good reason to tolerate wiring diagrams. It's like if a civil engineer's site would accept "artistic watercolor renditions of building structures". The common, clear, focused, abstracting nature of specific types of commonly accepted diagrams is mandatory, not an option, for communication of technical problems. \$\endgroup\$ – Marcus Müller Jun 26 '17 at 10:04
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    \$\begingroup\$ @shiz: Marcus already answer, and there is very little to add. Yes, I close posts as unclear when reading them is too much trouble due to sloppy writing, wall of text, blatant disregard for capitalization, runon sentences, and yes, wiring diagrams instead of schematics. Wiring diagrams have to be deciphered to understand the circuit, so they are in fact unclear. As Marcus said, we must not tolerate them for other reasons anyway. I call them "cartoons" to make the OP realize how silly they are, and maybe to shame them into not showing up without a schematic next time. \$\endgroup\$ – Olin Lathrop Jun 26 '17 at 11:48
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    \$\begingroup\$ @MarcusMüller and Olin - very good explanation. I was sure there was some good reasoning behind it, I just am not familiar enough with EE to pick that up on my own, and thought it would be a good question to ask. \$\endgroup\$ – schizoid04 Jun 26 '17 at 14:25
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    \$\begingroup\$ @OlinLathrop Didn't you lean anything form the fine engineers who bless us with their questions? Ground terminals should point upwards (so they look like antennas), while antennas always go sideways! Guess you really can't draw a genuinely poor schematic. \$\endgroup\$ – Dmitry Grigoryev Jun 27 '17 at 13:41
  • \$\begingroup\$ @OlinLathrop: does it make the amplifier boost lower frequencies? \$\endgroup\$ – Bryan Boettcher Jan 26 '18 at 23:36

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