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I opened this thinking I was the target audience - a longtime developer who has always wanted to get into electronics. However, this first paragraph...

> In order to present our paradigm in learning electronics, we can take an example of a full adder chip that enables binary addition. Let us use a top-down approach, and look at the datasheet of the TTL (Transistor-Transistor Logic) chip 7483. We will immediately notice that the chip performs the addition of two 4-bit binary words, A and B.

...and the associated diagram, just immediately left me feeling like I was standing in a room full of people who were smarter than me. Is this really where one starts while learning basic electronics?




I think this is mostly poor writing on the part of the author. You being able to "immediately notice" is contingent upon having read the data sheet, which was not linked nor reproduced, but the way it was presented made it seem like the diagram was sufficient. If you were to have read the data sheet, it would have stated up front that the circuit performs four-bit addition. But the page did not facilitate that...


> But the page did not facilitate that...

I had to do a lot of navigation to get to the first page of content; which dropped me straight into a 4-bit full adder. To my mind, that's logic circuits, not electronics.

To be fair, most intro-to-electronics pages start with Ohms Law and so on, which to my mind isn't electronics at all - it's basic electricity. This site starts with diodes, which is indeed the entry-point to electronics proper. But jumping in with gates is arse-over-tit; gates are a special case of amplifiers, and I think explaining transistors as amplifiers should precede explaning them as switches.

Regarding navigation: The whole thing is set in something like Courier, and links don't look any different from body text, even when you hover. And I generally expect no more than one click from the homepage to get me to page 1 of the content. A contents page that links to contents-of-the-contents pages seems like a rabbit-warren.


> this is mostly poor writing on the part of the author

Indeed. The correct way is:

"It is trivially obvious to the most casual observer that the chip performs the addition of two 4-bit binary words"


There should be a "clearly" in there as well as that word by itself is commonly believed to bring a lot of clarity.


If you look up a data sheet for any 7483 variant, it is immediately notable: the first lines are something like "4-bit binary full adder" and the description says "…accept two 4-bit binary words" If you skip to the next paragraph, you’ll see they are onto transistors. Ideally the author could show a data sheet, but there may be reasons they can’t.

I found the material that followed to be a clear exposition of the fundamentals – this is as somebody who has tried to learn electronics over the years but nothing ever stuck. This did a better job than anything else at a pace that is about right for me.

But YMMV and I personally relish being in a room full of people who are smarter than me.


Thank you sir! I am grateful for your positive outlook and support


In my experience in a university ECE program, you'd start with understanding the high level properties of transistors, then combining transistors to make AND and OR gates, then XOR and other gates, then MUXes and half/full adders, then flip-flops and eventually into synchronous (clocked) logic.

The lab component of such coursework did start with TTL chips but the timing of the coursework was such that you'd have most of the asynchronous logic theory taught by the time the chips came out.


Was it an Electrical Engineering, Electronics Engineering or Electrical Engineering Technology Program? My digital course skipped over transistor level and spent that time on basic FPGA's instead.


Not OP but I did Electrical and Electronic Engineering undergrad and we started with diodes at the materials level, then BJT and FET transistors, then logic gates, flip flops, timers, ALUs and eventually working up to build a Motorola 68K micro controller from mid level components. There was some VHDL and FPGA in the later stages as well from memory.


In my experience all serious electronics/electrical engineering learning material is written like this, as if the student knows everything about electronics except the one topic the author is explaining. Probably an artifact of being written for industry users. You can get used to it though, kind of putting boxes around certain circuits and just looking at behavior without asking how it works until you need to understand then doing a deep dive.


You are plenty clever.

This is the equivalent of introducing programming by giving a piece of ARM assembly and stating that it is immediately obvious that we are dealing with a merge sort implementation.

I’m not sure why, but I see this often in other domains as well. Math in particular. I guess it’s the curse of knowledge.


Except that when I was in highschool, programming in assembly was not in the curriculum, but designing simple logic circuits was. I am pretty sure we practiced designing a half adder in physics class as part of the electronics chapters.

The bad part of the writing is the assumption that all that technical language and knowledge is stil at the top of your memory when you just picked up this book.


I don’t know what high school you were in, but that is not the norm.


I no longer have the textbooks obviously, but it was just a regular gymnasium in a provincial town (Leeuwarden), we were using the standard government recommended VWO textbooks too, just under 20 years ago. I'm pretty sure it was in the textbook because the teacher was not the type to go off book and teach us something not needed for the tests.

We had those electronics circuit practice boards and you could hook multiple up together to make a half adder.

A group of students that were acing the tests and finishing their homework were spending a couple weeks of time in the back of the class assembling a full adder out of literally all of the practice boards the school owned. I wasn't acing any tests and wasn't finishing my homework on time but I joined them anyway because it was more fun. My contribution was realizing that we could use the relais as and and gates, doubling our resources enabling the completion of the full adder.


You had a good education. Don’t discount “provincial” schools.

> A group of students that were acing the tests and finishing their homework were spending a couple weeks of time [..] assembling a full ladder

Let’s just say I was submerged in a … different socio-economic class.


I wish we had done anything of that sort in my high school.


Dear kaishiro, thank you very much for the observation. Really makes sense! I changed it a little bit to be less 'discouraging', because you really are a target audience. It is my "poor writing", as noted, that sometimes takes over :) Please let me know if this makes more sense.


I once took a computer architecture course from the designer of the Burroughs 6700, who had us do a similar exercise. But that was back when people actually built things out of 74xx TTL. Few people do that any more. It would be very unusual to use a 4-bit adder chip today, unless you're deliberately doing retro stuff. And even more unusual to start there. Also, a 4-bit adder, a stateless device, is only useful when surrounded by latches and clocks so that something useful happens.

Here's a real beginner level presentation, from Adafruit.[1] This may be too simplified for some.

The Art of Electronics by Horowitz and Hill is highly recommended, but the original audience was physics grad students who needed to build instrumentation for physics experiments. The order of presentation is good, but it's a big book. Because it mentions current components by part number, the book ages rapidly.

[1] https://learn.adafruit.com/guides/beginner


> Is this really where one starts while learning basic electronics?

Hmm did you miss the introductory chapter that starts with diodes, transistors and basic logic gates that they told you vaguely about in high school physics?

There's quite a bit of info before getting to using the TTL chips.

Having played a bit with redstone circuits in Minecraft helps too - or knowing about diodes and transistors when doing redstone in Minecraft helps :)


The real start is on the next pages which goes into _real_ deep intro for Diodes and transistors. I think it was just a matter of giving an intro but overseeing that people don't know what these symbols mean.

For me, an electronics engineer by degree (not by trade), it was so basic I could see the author forgetting this.


Thx 4 the ‘overseeing’ comment, it is important never to loose that aspect when addressing the reader!


I would say no, unless that is the kind of stuff you are specifically interested in.

You will probably never see a full adder chip outside of retro and tinkerer stuff. If there are commercial uses left, they might be gone and replaced by FPGAs soon.

If someone asked me to teach them the more modern way, more appropriate for someone who wants to make props or puzzles and stuff as opposed the more retro experimental stuff, I'd advise a bit differently.

I would probably tell them to start with an ESP32 powered Arduino module, and some op amps, because op amps are both easy to understand and practical.

And at the same time, brush up on your pure mathematics side stuff, if you don't want to be like me, not really able to do any of the super high end stuff.

At the basic level you won't even need algebra, as you do more advanced work the math gets heavier.

Before even touching a real circuit, go immediately to the Falstad Simulator, and check out their example circuits. No, it's not perfectly accurate, but it is an amazing tool and runs right in a browser.

I think there's a lot of stuff that is kind of cool to try out for educational purposes that might be best just left in the simulator, at least at first, so you don't have to buy a bunch of stuff just to try out, and then not know what to do.

Probably don't buy a name brand soldering iron, a Pinecil V2 is probably about what you want, or a random T12 station.

The current good cheap multimeter changes every week it seems, the no name stuff is always changing, IIRC right now it's the HT118 or something that a lot of people like, but I could be wrong.

Oh, and don't invent a brand new standard and decide you're going to make all your stuff compatible with it, make up a bunch of custom cables, etc. There's a high risk of being bored, or finding some new universal standard for everything, and winding up with piles of useless junk.

Just buy the parts you need for one project at a time. USB-C and barrel jacks are good. Don't use too many weird connector types, because cables take up so much space and are a really annoying kind of junk to have around.

Wagos and premade pigtails are your friend for making up adapters.

Learn the E3 resistor and capacitor values, see if you can keep to mostly just those, if you want to reduce the number of different parts you need.

Most intro tutorials don't cover a lot of this stuff I wish I had known....


It might have to do with how longtime "longtime developer" means.

I took a look at TFA because of this. My experience caps out at doing a few heathkits in the early 80s and one single soldering of a resistor on my Synology to repair an issue a few years ago. I *mostly* understood the diagram, most of which was due to seeing it during CS adjacent classes in the early 90s.

Unfortunately it's often the case that these ELI5 type articles assume baseline knowledge that's less than baseline.


I'd recommend the book "Practical Electronics for Inventors". For me it had the right balance between not making too many assumptions but still teaching interesting circuits.





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