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the problem with 4 pictures

This is a test question in a study book about electronics. I cannot find the answer and have no idea which picture identifies a pin.

Am I missing something? Any help on the right answer along with why that answer is correct would be helpful.

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    \$\begingroup\$ Do you have any more examples? It looks like an awfully designed test question/study book... \$\endgroup\$ – Shamtam Feb 10 '17 at 1:12
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    \$\begingroup\$ Shamtam, I agree that this is an awful question. This is very frustrating. It doesn't make any sense to me. I've never seen a question that asks you to identify Pin 1 from these angles. That picture is all the info they give. \$\endgroup\$ – Stremdawg Feb 10 '17 at 1:15
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    \$\begingroup\$ I meant if you could show the other two problems (1-36 and 1-37 presumably)? If they're equally ridiculous, I think I'd just chalk it up to a poorly-designed convention that this book is using. \$\endgroup\$ – Shamtam Feb 10 '17 at 1:19
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    \$\begingroup\$ Weird how the left side trough hole in the cross sectional views A, B and C only have copper plating drawn on the left half of the hole. \$\endgroup\$ – jms Feb 10 '17 at 1:27
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    \$\begingroup\$ If you are trying to study electronics from idiotic books like this, I don't think you will learn anything useful. Where did you get such nonsense? What kind are the "problems" 1-36 and 1-37? \$\endgroup\$ – Ale..chenski Feb 10 '17 at 1:49
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I expect this to be a typographical error. They used the wrong picture to illustrate the question. In this case they used the same picture as the one used in question 2-28. The questions 1-36 and 1-37 have good images to identify the pin1 and I assume something similar was intended for the question 1-35.

A pdf version of the book is this, and question in case is at page 162.

enter image description here

enter image description here

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    \$\begingroup\$ That's cool. How did you find it? Assessment questions shouldn't be this wrong. I had left eating from the time I had read the question. \$\endgroup\$ – Umar Feb 10 '17 at 13:35
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    \$\begingroup\$ @umar, I used google to find the book, and for this kind of books (small edition, in-house printing, limited availability) the typographical errors are not an exception, anecdotally. \$\endgroup\$ – valentin Feb 10 '17 at 13:42
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    \$\begingroup\$ Identifying pin 1 of a flat pack IC? Didn't flat packs become obsolete decades ago? (Serious question; let me know if they are still in use.) The pdf has a date of 1998, but everything it discusses is 1960s or 1970s technology. This book is too obsolete to be worth learning from. (But very cool valentin that you tracked it down.) \$\endgroup\$ – Ken Shirriff Feb 10 '17 at 18:21
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    \$\begingroup\$ Wow, and one of the next questions (1-38) is also unanswerable: depending on the part and manufacturer, the markings may provide any (or even none) of those pieces of information. \$\endgroup\$ – duskwuff Feb 10 '17 at 18:55
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    \$\begingroup\$ @Ken Shirriff Navy and electronics should be dead giveaways. In some cases, military systems might be in use for many decades, in some cases with little to no modifications. When that is combined with technological inertia of safety-critical systems, result is that there's a good chance that a technician could encounter 20 or 30-year old system, which used 10-years old technology when it was manufactured. The 1960s and 1970s don't look so old now. \$\endgroup\$ – AndrejaKo Feb 10 '17 at 19:04
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This question makes no sense.

First and foremost: The letters don't identify pins. They appear to identify four separate diagrams, each depicting a separate part! At best, we can imagine that each letter is meant to label one of the two pins on each of four different parts; even then, though, each of those parts would theoretically have a "pin 1".

Second: Pins are typically not numbered on radial packages of the type shown in these pictures. If a part is polarized (e.g, a diode or electrolytic capacitor), the pins may be identified as "anode/cathode", or "positive/negative", but I have never seen them designated with numbers.

Third: Even if we were to assume that these diagrams were meant to depict polarized parts, and that the book used some standard for numbering their pins (1=anode / 2=cathode perhaps?), the identifying marks which would be needed to identify them are all absent! A diode or electrolytic capacitor would typically have a stripe or bar near one end, for instance. However, all of the components in these diagrams are completely unmarked.

If I had to guess, I'd say the diagrams are meant to be paired with a completely different question, along the lines of "which of these components is mounted correctly" (to which the correct answer would be C).

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  • \$\begingroup\$ I don't know if this helps but there are more pictures: link \$\endgroup\$ – jkd Feb 10 '17 at 9:26
  • \$\begingroup\$ The question makes no sense, yet instead of voting to close you decided to answer it? \$\endgroup\$ – Dmitry Grigoryev Feb 10 '17 at 11:00
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    \$\begingroup\$ @DmitryGrigoryev : the question in the book makes no sense, the question of the OP most definitely does. \$\endgroup\$ – mikołak Feb 10 '17 at 11:09
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    \$\begingroup\$ @DmitryGrigoryev : I'd rather say, having read beyond the heading, that the actual question is "how to make sense of this weird question in an electronics textbook?". \$\endgroup\$ – mikołak Feb 10 '17 at 14:08
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    \$\begingroup\$ @DmitryGrigoryev I try hard to not get drawn into "somebody is wrong on the internet" battles. BUT I am utterly appalled at your comments here. They show no understanding of the OP's question or his predicament. The question is good, the answers are good. For you to say that milolak's reasonable and logical comment sounds like a rant in disguise sounds like a troll or perhaps ulterior motive. | This question has 10 upvotes. I consider the 2 downvotes and 3 votes to close as examples of small minds and limited vision and understanding of real world situations. || <Shields_up> :-) \$\endgroup\$ – Russell McMahon Feb 15 '17 at 1:34

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