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Offline netwinderTopic starter

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Electronics intervention ramble
« on: August 20, 2015, 10:27:29 pm »
Hello EEVblog forum,

Small warning... I ended up with more text then what i wanted, if you do enjoy reading small rants and general rambles feel free.  :blah:

This is a self-electronics intervention. A little about me, i love electronics, i love Linux based operating systems and i do occasional kernel and software development for Netwinders (very old ARM servers), i enjoy tinkering around with my home server (Ubuntu server), and i enjoy network architecture. I was always fascinated by electronics, my father and grandfather were avid in electrical engineering as a hobby and a profession. I've been practising electronics and some basic electrical engineering recently, I completely re-did my lab to make work flow a lot better. I got some new (old but new to me) equipment that needed some fixing and/or calibration (the most significant would be a wavetek 154). I am looking to get a digital oscilloscope in the future, but that is what this post isn’t about.

What it is about is, how to i get bitten by the electronics bug. I grew up around technology, when I was young i remember poking around on windows 98 and trying out "the google". I do conciser myself to have a very technical background and passion.. But when it comes to electronics, i can sit down with a book (the art of electronics) and read the theory it has and understand it, but when it comes to applying it. Be it sitting at my lab with a blank breadboard, or sitting on eagle trying to think out a design (its like writers block). I do remember having a similar moment, not with electronics. I tried to learn python. I started off with a blank screen in an IDE, and eventually with googling some code (quadratic solver) and i figured... This could be done better. So i looked at it, and eventually coded a pretty nice quadratic solver. I know this isn’t a programming forum, but if anybody curious ill post it.

But with electronics... I cant get over that block. Im just stuck having to reference a pre made design. And i still find a way to mess them up. An example is i watched Dave's op amp video. I loved it. Absolutely understandable, just perfect. So i took notes, and i copied the op-amp circuit he did at the end of the video. I laid it all out on a breadboard, hooked up a supply and my waveform generator, and i probed the input waveform, it showed up fine, i probed the output... Looked like garbage. I checked that i had the right voltages, components, tried different op amps... Eventually i gave up. Regardless of what i did, nothing worked. Perhaps I’m just cursed by the electronics bug? I even tried something foolproof (sort of) i found a 555 LED flasher circuit online, so i copy it into eagle, design a board, do a toner transfer method and then etch with a ferric chloride alternative. The board turned out as expected, no bridges or any open circuits. Anyway i test all the components, wire it up and.. nothing. I did try reversing the LEDs, maybe i screwed up cathode with anode, and nope. Nothing. I’m not looking for solutions to the electronics problems, i did find some clues as to why the circuits didn’t work.

Really what it comes down to is, how do you get into a loop of working with electronics. For some its natural, i get that. I seem to pick up theory pretty quickly and i can discuss it with people however when it comes to applying said theory, its absolutely hopeless. One thing i have done is reverse engineer and troubleshoot the vertical deflection amplifier of an oscilloscope, still not fixed yet but its making progress. I have fixed the screen out of a fluke 8010A, really it was fixed by theory. The old screen was damaged, and all i did was find a data sheet for the LCD driver, find which pin on the board did, and eventually made a conversion table and wired a new screen. The screen does glitch occasionally but oh well.

Again, as a re cap my question to all of those whom made it this far in the post (and i do thank you if you have made it this far) is how do you get out of writers block when doing electronics, read more theory? become more antiquated with physics?. Other question is, am i just wasting my time running in circles with electronics? Any tips and opinions would certainly be helpful

Thank you for your time guys, I really appreciate it.
 

Offline PA4TIM

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Re: Electronics intervention ramble
« Reply #1 on: August 20, 2015, 11:47:48 pm »
Most times I have more ideas for projects as time. So no writerblocks here. I design all my projects and 99% of the projects succeed.
www.pa4tim.nl my collection measurement gear and experiments Also lots of info about network analyse
www.schneiderelectronicsrepair.nl  repair of test and calibration equipment
https://www.youtube.com/user/pa4tim my youtube channel
 

Offline netwinderTopic starter

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Re: Electronics intervention ramble
« Reply #2 on: August 21, 2015, 12:06:41 am »
Thats interesting, where did you learn? I am entirely self taught.. Any tips on design workflow and general thoughts?

Sent from my D6603 using Tapatalk

 

Offline DimitriP

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Re: Electronics intervention ramble
« Reply #3 on: August 21, 2015, 12:37:24 am »
I avoided quoting the whole thing but after reading all your words, what I was left with,  in summary was :
"I read, I understand, I can't seem to come up with a  design of my own and when I tried to build "proven" designs" I couldn't them to work."

So...... it seems Rule #1 is. Never give up. Get it to work.
Rule #2. After you're fed up with it and you want to throw it in the microwave and watch the sparks (might as well get some use out of it), take a break and Read Rule #1.

It would be pointless to "come up with your own design", build it and .....not being able to get it to work.

Somewhere in the hours or months that it will take you to figure out what the problem was (the backwards installed socket or the solder blob shorting two pins together or the 220K resistor that was really 22Ohms) or the capacitor in series with V+) either it will become easier and more fun figuring things out, or you will decide that although you "like it", you and a soldering iron should not be in the same room if the iron is plugged in.   :)



 

   If three 100  Ohm resistors are connected in parallel, and in series with a 200 Ohm resistor, how many resistors do you have? 
 

Offline HackedFridgeMagnet

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Re: Electronics intervention ramble
« Reply #4 on: August 21, 2015, 12:48:04 am »
get the oscilloscope, you will never get far without one and an analog scope can only get u so far.

the 3rd edition "Art of Electronics" as a reference and a reader will get you a long way so you're on the right track there.

I am guessing your problem is you don't actually have a good understanding of the theory side of electronics so It makes it hard to apply it.

When debugging circuits you should have an idea of what waveform you expect at each node of a circuit. Probe around and look for anomalies.

The order of checking digital circuits goes something like this.

Probe all grounds first. If any of these are wrong you will get the weirdest of problems.
Then power rails.
Then clock.
Then voltage levels of digital IO. ie make sure they are all showing nicely formed square waves from Vcc to Ground or steady at Vcc or Ground.
Check no inputs floating.

If probing linear circuits watch for signals hitting the rails that shouldn't.
etc... etc...

and if you can't solve a problem, don't leave it, you need to find out why.
The forum can help with specific probelms and if you have a digital Osc then you can post waveforms.  :)
 

Offline rs20

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Re: Electronics intervention ramble
« Reply #5 on: August 21, 2015, 12:54:48 am »
I'm stealing Dave's rhetoric here, but I'm happy for you that your circuits don't work -- because when you figure out why they're not working, you'll learn something new. I think the only "quality/curse" I have is that if an electronic circuit doesn't work, and I don't know why, I cannot just leave it as a mystery. If you feel the same way, then you shouldn't give up because you're spurning some of the purest learning opportunities you'll ever come across.

If you just give up and move on to a new project everytime something seems a bit broken, you'll have a big history of failures. If you get each project to work, or at the very least figure out exactly why they don't and learn something in the process, you'll have a smaller history of success and valuable failures. So I agree with DmitriP -- get it to work! The forum is here to help you with those specific questions, no matter how basic.
 

Offline TerminalJack505

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Re: Electronics intervention ramble
« Reply #6 on: August 21, 2015, 01:00:33 am »
You might try playing around with circuit simulator software.  You can "build" circuits with them just as quickly and you don't have to worry about smoking parts.  If you don't have your own test equipment then a simulator can actually provide more insight into a circuit than you would get by making it.

Once you get comfortable with a circuit in the simulator then you might try it on the breadboard.
 

Offline netwinderTopic starter

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Re: Electronics intervention ramble
« Reply #7 on: August 21, 2015, 01:13:04 am »
Thanks everybody for the insight! I do really appreciate it  :)

Thank you dimitriP, your summary is accurate and i do agree with the rules. Sometimes troubleshooting a simple function generator can turn into grinding my forehead with a cheese grater. But i will see about following rules 1 and 2.

Quote

get the oscilloscope, you will never get far without one and an analog scope can only get u so far.

I have been looking at scopes, and i do have my eyes set on one. I dont intend this turn into "what dso to buy" but so far ive gotten by with my tek 465 and a timer/counter. Right now i am working on my oscilloscopes vertical issues, but i am fairly close to a solution (or that famed blue smoke)

Also i've taken systematic troubleshooting methods as such, and sometimes they do indeed work.

Quote
If you just give up and move on to a new project everytime something seems a bit broken, you'll have a big history of failures. If you get each project to work, or at the very least figure out exactly why they don't and learn something in the process, you'll have a smaller history of success and valuable failures.

I agree, i also agree with the beginning of your post. I try not to leave the electronic problems a mystery. But eventually writers block takes over and it turns into me rubbing my forehead against a cheese grater  |O

Quote
You might try playing around with circuit simulator software

I could, not familiar as to any of the common ones. The art of electronics recommends spice.. To be honest i haven't looked into it, i will research some circuit simulators, thank you
 

Offline HackedFridgeMagnet

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Re: Electronics intervention ramble
« Reply #8 on: August 21, 2015, 03:12:46 am »
 

Offline rs20

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Re: Electronics intervention ramble
« Reply #9 on: August 21, 2015, 06:09:30 am »
Obligatory EEVBlog reference (episode #017!!):

https://www.youtube.com/watch?v=_pGk6GYDnes#t=1m40s
 

Offline kizzap

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Re: Electronics intervention ramble
« Reply #10 on: August 21, 2015, 10:51:50 am »
Nothing wrong with reference designs. just because you have the design for the circuit, doesnt mean you can't change values in it to see how it will affect it?

The only other real option is to start with an idea for a project you want to make, and slowly add the functional blocks you need to develop to get that outcome you want.
<MatCat> The thing with aircraft is murphy loves to hang out with them
<Baljem> hey, you're the one who apparently pronounces FPGA 'fuhpugger'
 

Offline PA4TIM

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Re: Electronics intervention ramble
« Reply #11 on: August 21, 2015, 06:41:42 pm »
Thats interesting, where did you learn? I am entirely self taught.. Any tips on design workflow and general thoughts?


Also self taught. The art of electronics, ARRL handbook, Rothammel, several duch books, expirental methods in RF design ( Hayward), RF circuit design (Bowick), trouble shopoting analog circuits from Pease, the appnote books from Williams, The books from Frederick E Terman and many others)
Watched things like the Feynman lectures on you tube.
Learned a lot from playing with testgear  and even more through repairing them (Bridges, slotted line, scopes, curvetracer, SNA, VNA, SA etc)
A good friend helped me a lot in the begin. One of the first things he let me do was designing and building a ssb receiver based on a IC. Learned a lot from that. Then I got an old scope that was dead and through a forum I came in contact with an EE who is very good in repairing and designing. We still have a lot of contact and he  became a very dear friend. I learned a lot from him.

One of the ways he uses is a nice one. We brainstorm about a project we both would like to design, always some sort of measurement gear.
Then both do some raw designing. Then we come together and discus the designs and end up with something we both use as a base.  We use the same functional blocks. But from there we follow our own path. We still share designs and use each others ideas if we like so.
This way we build a 25MHz to 2GHz (sweep) generator and a AC+DC 500V/10A/ upto at least 500kHz powermeter.

At the moment I'm to busy for a new project.  A year ago I started a small business in repairing test and calibration gear. 



www.pa4tim.nl my collection measurement gear and experiments Also lots of info about network analyse
www.schneiderelectronicsrepair.nl  repair of test and calibration equipment
https://www.youtube.com/user/pa4tim my youtube channel
 

Offline drws

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Re: Electronics intervention ramble
« Reply #12 on: August 21, 2015, 07:51:54 pm »
I'm in a similar situation, background in servers/networks etc. with an interest in electronics (I did it in school decades ago and wished I'd stuck with it).
Did physics/maths at Uni. Physics helps me understand how a capacitor works, it doesn't help me as when/how to use them so much.

One thing I had to do was re-align my expectations as to how fast I should be progressing.

For example, when I learnt Python many years ago I found it easy, but I had a base to start from in that I knew C, Perl etc and others. The ability to quickly learn those can probably be traced back to Basic on my ZX81 and C64. Each new thing builds on my previous knowledge.

So now when trying to learn and troubleshoot electronics, I just remind myself that I don't have a lot of historic/similar knowledge to base new understanding on, so I must expect to learn at a different pace, through trial and error error error.   |O :-BROKE

well, that's how it feels anyway.
 

Offline netwinderTopic starter

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Re: Electronics intervention ramble
« Reply #13 on: August 21, 2015, 10:15:17 pm »
I'm in a similar situation, background in servers/networks etc. with an interest in electronics (I did it in school decades ago and wished I'd stuck with it).
Did physics/maths at Uni. Physics helps me understand how a capacitor works, it doesn't help me as when/how to use them so much.

One thing I had to do was re-align my expectations as to how fast I should be progressing.

For example, when I learnt Python many years ago I found it easy, but I had a base to start from in that I knew C, Perl etc and others. The ability to quickly learn those can probably be traced back to Basic on my ZX81 and C64. Each new thing builds on my previous knowledge.

So now when trying to learn and troubleshoot electronics, I just remind myself that I don't have a lot of historic/similar knowledge to base new understanding on, so I must expect to learn at a different pace, through trial and error error error.   |O :-BROKE

well, that's how it feels anyway.
I completely see what you're saying.. Makes sence, anyways i found that having a good reference to learn off of does make a differenge however applying such knowledge can be tedious. It was like first learning to code (with C doing kernel development/making small console apps) i knew how to make the structure, but actually filling it with with stuff other then "hello world" seemed strange. Luckly compilers can tell you what youve done wrong, with electronics its going to be blue smoke ;)
 

Offline eas

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Re: Electronics intervention ramble
« Reply #14 on: September 01, 2015, 10:21:25 pm »
I started getting into electronics earlier this year. I came up with a problem I wanted to solve that I thought would have a fairly simple solution (because I thought I had the outline of it). Then I started breadboarding out parts of the circuit. Then things didn't work as I expected, so I tried different things, looked at a simulation, read more, etc. Then I decided it would be easier if I had slightly better gear, so I bought some. I'm still not done with my simple project.

I've learned a lot though. One of the most important things I learned is that having a known-good design, with known good but broken implementation (ie a used bench PSU that no longer works right) was much more engaging and motivating to me than flailing around with basic circuits. So, for now, I've put my attention to buying used lab equipment and fixing it.

I find that motivation is often the most mercurial part of learning. I like reading about the theoretical underpinnings of things, but for most of my adult life, I end up getting frustrated with myself if that theoretical understanding isn't serving another goal.

In my early 20s, I tried to learn C with the idea that I'd become a software developer (I'd dabbled in BASIC in my early teens, and done some Pascal programming as part of my Physics class), but that goal ended up being too vague and distant to get me to slog through the difficulties of learning enough about C, and event-loops, and the Macintosh Toolbox to actually get even a rudimentary program running "from scratch."

A few years later though, I had a problem that I could get paid to solve, and the only sensible way to solve it was by writing some software. I learned both enough Visual Basic and enough Perl to do what needed doing. A few years after that, I was again entertaining the idea of moving into software engineering, and I had some time free, so I came up with a project idea and started teaching myself java. Again, I didn't get to far, because again, the goal ended up being too remote to motivate me.

A couple years later, I'd given up on the idea of being a programmer, but I still wanted to gain more programming proficiency so I could make prototypes, and automate some data analysis. This time, I picked python and the Django framework. Between the two, it was pretty quick and easy to get something rudimentary working, and once it was working, it was easier to keep going. I'm still a fitfull programmer, but I'm finally to the point where I can start something from scratch and get to the point where it does enough to maintain my motivation.

I struggled through most of high school, but the classes I did best in were generally ones where I found people to study with. I did much better in college, in part because I had study partners in both of my classes. In retrospect, I realize that part of my motivation in those situations was collaborating with a peer, and one of the rewards of that collaboration was being able to practice and refine my knowledge by explaining things to my study partner. Similarly, if there was something I didn't get, I could get their help in getting over the hump.

Of course, the process of learning often isn't a continuous stream of steady rewards. There are times where you may have to grind your face against a cheese grater until you are raw, then get up and do it again the next day. As kids, this is often the dominant factor of learning. I think of how many times I failed to even come close to tying my shoe, or ride a bike before suddenly, almost overnight, I could do it. But as a kid, you are learning so much about so many different things, you don't really realize how hard it is, its all you know. Also, as a kid, you don't have much responsibility besides learning. Most parents aren't going to put their kid out on the street, without food or clothing, because the kid needs another month to learn to tie his or her shoes. For adults though, too much grinding your face against a cheese grater is discouraging. This one reason why (some) adults don't learn new things, because they feel like helpless children, which won't do, because they are adults.

So, my suggestion is: Think about what has motivated you in the past, and pay close attention to what motivates you now. Go with what works for you, not some abstract ideal that worked for someone else (or at least they think it did). Be patient with yourself. Don't beat yourself up because you are struggling. Just do the best you can, when you can, sleep on it, and then come back to it again  -- this is actually a really important cycle in learning, struggling with something can, given some time and sub-concious processing, lead to breakthroughs, but only if you keep returning to the problem.

Some specific advice: There is nothing wrong with "writers block," not in and of itself. The mistake is to let it scare you away, or drive you mad. Instead recognize that "writer's block" is often a symptom of knowing and understanding less than you thought you did. I think the trick is to try and find the cracks and the edges of the block, to better understand the gaps in your understanding and your thinking. That can be frustrating and slow work, but its what leads to those epiphanies in the shower, those periods of productive flow.

There is an author named John McPhee. He has had a long, successful, career writing non-fiction. Most of it has appeared as long essays in the New Yorker before being collected and released as books. He said that his typical day involves getting up in the morning, having breakfast, etc, and then spending ~7 hours in his office, sharpening pencils, organizing papers, etc. Its only the last hour or so of the day where he actually sits down and writes. The thing is, he'd never get that hour of writing down without the ~7 hours of procrastinating and cogitating. Doing that 5 days a week has been enough to make him a productive and successful author. Other productive authors have different routines. I think the same is true of any creative/intellectual work.
 

Offline fivefish

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Re: Electronics intervention ramble
« Reply #15 on: September 01, 2015, 10:44:19 pm »
I see nothing wrong with using proven/datasheet designs as the basis of your own design.

In electronics, you stand on the shoulders of others that came before you.

Just like in programming, break a big concept/project down into little functional pieces, and then glue them all together.

Little successes create confidence and experience to tackle on bigger projects.

I find out I learn more when I'm actively troubleshooting, than when I'm passively reading something.

The pressure to fix something is proportional to how much money I've invested in the non-working gear I bought, or cost of kit I'm trying to build.
 

Offline CatalinaWOW

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Re: Electronics intervention ramble
« Reply #16 on: September 01, 2015, 10:50:45 pm »
The circuits you describe failure with are nearly bullet proof.  Meaning that you have missed something obvious, possibly something so fundamental that it wasn't covered in the videos and texts you are referencing.  Something analogous to omitting a key header file in a c program or the difference in bit sequence between some processor families.  It could be something as fundamental as misinterpreting the pin numbering conventions. 

I would recommend that you go back to your failed circuits and go through the ICs pin by pin starting with pin 1 and see if the signals on each are what you expect.  Notes at this stage can be helpful.  If all is well great, move on to the signal source and so on.  If not, think about why there might be differences - is it an error in your understanding or in the fabrication of the circuit.  This is the point where questions on a forum like this can be helpful. 

Don't be ashamed or embarrassed because of this block.  We all have had them, and will all run into more.  They almost always seem trivial when the understanding finally happens, but they are very real up until that moment.  Once you have gotten through the block you can move on to modifications, improvements to and extensions of the reference circuits.
 

Offline sarepairman2

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Re: Electronics intervention ramble
« Reply #17 on: September 02, 2015, 02:08:13 am »
i must have killed like 5-7 555 timers making my first led lamp dimmer lol, the radioshack by my house almost installed a revolving door because of me. i ended up soldering a fucking socket down after frying the first few
 

Offline ez24

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Re: Electronics intervention ramble
« Reply #18 on: September 02, 2015, 02:40:51 am »
YouTube and Website Electronic Resources ------>  https://www.eevblog.com/forum/other-blog-specific/a/msg1341166/#msg1341166
 


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