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Electronics => Beginners => Topic started by: lordvader88 on July 25, 2018, 09:12:41 am

Title: When you follow the schematic but it doesn't work
Post by: lordvader88 on July 25, 2018, 09:12:41 am
I'm reminded of 2-3 times I tried to make a C-R oscillator w/ a BJT and maybe an op-amp once, and they never worked. I didn't try changing much, but it never worked. I bet the schematics were fine tho.

Then 1 utuber, an old radio guy, with proper schematics from an old book, I tried 2-3 little circuits and they never worked but his did. With those it was probably the BJT or JFET not being quite right, and not getting the loop gain right.



Don't you hate it tho when you follow a schematic and it doesn't work and you don't know why ? (time to re-try some)
Title: Re: When you follow the schematic but it doesn't work
Post by: bd139 on July 25, 2018, 09:22:22 am
yes very annoying. This is what got me interested in the design side of electronics if I'm honest.

I built some stuff from Practical Wireless magazine in the early 1980s that didn't work. I learned pretty quickly that a lot of the designs out there are total shite and nothing is trustworthy. The design may have worked for one person once. In some cases, I don't think the design ever worked even if the author said it did and in other cases it was actually misprinted and you'd find out two months later in a footnote on a page after you had recycled the thing for parts anyway.

Putting effort into learning why things don't work and actually looking at a design and going "huh?" has been a valuable set of lessons though.

To note, a lot of stuff we were taught at university didn't work either!

Finding stuff that should work but doesn't and making it work again is the best analytical training you can get I think.
Title: Re: When you follow the schematic but it doesn't work
Post by: lordvader88 on July 25, 2018, 09:32:11 am
Quote
To note, a lot of stuff we were taught at university didn't work either!
You mean schematics out of text books ?
Title: Re: When you follow the schematic but it doesn't work
Post by: bd139 on July 25, 2018, 09:33:03 am
Yes out of textbooks and as advised by the lecturers. It's almost as if they'd never built the things  :palm:
Title: Re: When you follow the schematic but it doesn't work
Post by: GeorgeOfTheJungle on July 25, 2018, 10:21:55 am
We're well into the internet era, and a few years back many unis still didn't teach javascript, students can't even tell apart JS from the DOM, write async code, and barely know what's a closure if at all. If at least C were mandatory curriculum you could be assured they know well what's going on under the hood. But no. Java has been/was mandatory instead. Is it still? (IDK). On the plus side, it's no more any longer everything Windows, all Windows and no more than Windows.
Title: Re: When you follow the schematic but it doesn't work
Post by: HB9EVI on July 25, 2018, 10:32:01 am
Coming from the IT domain on college level, I'm still wondering about the classic dual system apprenticeship in IT here in CH. Those guys spend 4 years education, normally 3,5 to 4 days per week in an IT company and the rest in business school. You might think, they learn some bloody basics about IT like simple transistor circuits, flipflops,, Ohms law or logics or even the essentials about how a cpu is working:

Just forget it!

There are no essentials, no basics taught anymore nowadays. It just counts, that they know to maintain a windows installation or maybe set up PC from the basic components - but how the components actually work - no way.
they know every detail about the main tasks their companys are in; about webdesign, programming, troubleshooting some particular software or whatsoever - but as soon as they're out of their well known playground, they are lost. It's a shame
Title: Re: When you follow the schematic but it doesn't work
Post by: bd139 on July 25, 2018, 10:40:48 am
Yes out of textbooks and as advised by the lecturers. It's almost as if they'd never built the things  :palm:

You will be surprised how many university professors have absolutely no idea on fields that he/she is not exactly working on (we are ARWU ECE subject ranked top 10 worldwide).

I once had a professor, teaching communication protocols, who has no idea what's differential signal and how it increases bandwidth. She only knows RS485 is faster than RS232, but has no idea why.

And I also had a professor, despite living in US for 2 decades, has no idea about American slang and English memes. She likes to eat salmon, and every time she pronounces like she likes to eat semen. And she always says she likes to "blow", of course it's something else.

Actually in our department, it's hard to find a computer engineering/network engineering professor who can read schematics, and a few EE professors who can code properly (not just grabbing crap from CodeProject or Arduino forum).

And I kid you not, we have DSP topic PhD students working on the latest imaging processing technology that has no idea how to compute a 2N point real FFT with an N point complex FFT.

Again, we have power electronics major PhD students who absolutely master control theory, but has no idea how to actually drive a MOSFET or how to design a current shunt amplifier.

And yes, we do have people who don't know ground clips are always tied together, as we did have expensive firework shows. And we do have people who can't f*ing solder.

Welcome to 2018, where everyone knows nothing at all about fields outside his/her exact field.

That was exactly my educational experience 25 years ago. Sucks doesn't it?

We're well into the internet era, and a few years back many unis still didn't teach javascript, students can't even tell apart JS from the DOM, write async code, and barely know what's a closure if at all. If at least C were mandatory curriculum you could be assured they know well what's going on under the hood. But no. Java has been/was mandatory instead. Is it still? (IDK). On the plus side, it's no more any longer everything Windows, all Windows and no more than Windows.

They're teaching C# and nodejs at my local college and their staff have absolutely no fucking idea what they are doing. We have had a couple of their "graduates" in on trial and we're basically having to get them to unlearn a lot of stuff. I mean you don't write an OO program entirely in static methods ffs. But that's what they told us. Seriously, no.
Title: When you follow the schematic but it doesn't work
Post by: Dubbie on July 25, 2018, 10:45:02 am
I think it is a bit of a stretch to expect someone in IT to know much about electronics. They are usually working at least 5 or 6 levels of abstraction above voltages and transistors. You can’t learn everything.
Title: Re: When you follow the schematic but it doesn't work
Post by: Rerouter on July 25, 2018, 10:56:07 am
Trade schools cover more of this stuff, but most without prior knowledge are not given enough to fill the gaps, and have it click, meaning they know some keywords, but no idea how to apply it,

I was in a high level class discussing how to measure current and voltage in an industrial setting, and that it was difficult and expensive to interface to computer control systems... yeah I had a double take. Equally things like Wheatstone bridges drawn with inductors, and other non valid symbols.

I actually completed 2/3 rds of my 4 year course in 1 week, by demonstrating my understanding of the concepts by ripping in to a pile of stuff they had sitting around for repair for the past 5 years, (it meant I only had to pay 1 semester, so I wasn't too fussed on payment) Oh you want me to show ohms law at work... well this fuse has 25V across it, so its resistance must be high..  |O

Though the fun came from what form of programming they had on hand, they had very old gamepad programmed PLC's that used ladder logic, where I would solve the problem then reduce it down to the smallest possible solution. made anyone in the class copying my work stand out like a sore thumb. and resulting in test scores along the lines of "100%, It works, but hell if I know how?"

Back to the original topic, online schematics had me throw away a lot of money early on, It takes a while to build up enough Google-Fu to know when someone is talking about something they understand. and there is a stupid amount of simple circuit images out there that plain and simply will never work without the understanding of the weird quirk they used.

Title: Re: When you follow the schematic but it doesn't work
Post by: rsjsouza on July 25, 2018, 11:20:07 am
To the OP: the schematic diagram only tells part of the story, as it does not account for the influence the physical aspects have in a proper operation. In low frequency and low noise circuits (audio, sensors, etc.) this translates in poor signal to noise ratio, while in high frequency systems (RF, high speed switching power supplies, etc.) the interconnections become components themselves. Back in the day that was one of the great difficulties we had to build circuits straight from a reference such as John Markus' Guidebook of Electronic Circuits.

To top it off, I have a similar experience as BD139: many circuits in magazines seemed to be not thoroughly tested probably due to excessive reliance on a BJT or JFET's intrinsic parameters that greatly vary in a production run. I lost count of how many circuits were put aside and how many PCBs were thrown in the trash after trying to figure out why that radio or transmitter did not work or that audio mixer or pre-amp was so damn noisy. The losses were not as dramatical when I assembled them in screw terminal bars or (at a later time) in protoboards, but when soldered terminal bars or complete PCBs were used... (components were expensive at that time).

Obviously that, over the years, I learned a thing or two as of why these things didn't work, but it takes time and a lot of reading.
Title: Re: When you follow the schematic but it doesn't work
Post by: Alex Nikitin on July 25, 2018, 11:41:38 am
As far as I remember (and I've started to be interested in electronics when I was about 14) I've never built a circuit without understanding first how it works. I don't remember ever trying to build something from a circuit in a book or in a magazine without a thorough analysis which did always end up with me building my own circuits around somebody else's ideas. I've started with a simple multimeter and a soldering iron, several books on electronic devices (mostly data sheets for valves, transistors, resistors, capacitors and so on) and gradually built my own lab - a power supply, an oscilloscope, a function generator, an AC millivoltmeter - by the time I was 18.

I see no fun whatsoever in trying to build something you don't understand  :palm: .

Cheers

Alex
Title: Re: When you follow the schematic but it doesn't work
Post by: TK on July 25, 2018, 11:54:36 am
Yes out of textbooks and as advised by the lecturers. It's almost as if they'd never built the things  :palm:

You will be surprised how many university professors have absolutely no idea on fields that he/she is not exactly working on (we are ARWU ECE subject ranked top 10 worldwide).

I once had a professor, teaching communication protocols, who has no idea what's differential signal and how it increases bandwidth. She only knows RS485 is faster than RS232, but has no idea why.

And I also had a professor, despite living in US for 2 decades, has no idea about American slang and English memes. She likes to eat salmon, and every time she pronounces like she likes to eat semen. And she always says she likes to "blow", of course it's something else.

Actually in our department, it's hard to find a computer engineering/network engineering professor who can read schematics, and a few EE professors who can code properly (not just grabbing crap from CodeProject or Arduino forum).

And I kid you not, we have DSP topic PhD students working on the latest imaging processing technology that has no idea how to compute a 2N point real FFT with an N point complex FFT.

Again, we have power electronics major PhD students who absolutely master control theory, but has no idea how to actually drive a MOSFET or how to design a current shunt amplifier.

And yes, we do have people who don't know ground clips are always tied together, as we did have expensive firework shows. And we do have people who can't f*ing solder.

Welcome to 2018, where everyone knows nothing at all about fields outside his/her exact field.
You are quoting one extreme of the spectrum.  I am sure there are some amazing professors on the other extreme and a bunch of average in between.  Look for the world changing extreme, not the mediocre one.
Title: Re: When you follow the schematic but it doesn't work
Post by: b_force on July 25, 2018, 11:55:49 am
As far as I remember (and I've started to be interested in electronics when I was about 14) I've never built a circuit without understanding first how it works. I don't remember ever trying to build something from a circuit in a book or in a magazine without a thorough analysis which did always end up with me building my own circuits around somebody else's ideas. I've started with a simple multimeter and a soldering iron, several books on electronic devices (mostly data sheets for valves, transistors, resistors, capacitors and so on) and gradually built my own lab - a power supply, an oscilloscope, a function generator, an AC millivoltmeter - by the time I was 18.

I see no fun whatsoever in trying to build something you don't understand  :palm: .

Cheers

Alex
Lol, that's a very interesting thought.
It really depends how someones brain works.
Some people prefer understanding every single little fart before they start.
Other people learn as they go.
(and some people can't be really bothered)

Neither of the two is good or wrong and it both has its pitfalls.
Title: Re: When you follow the schematic but it doesn't work
Post by: Richard Crowley on July 25, 2018, 11:58:17 am
One of my favorite corollaries of Murphy's Law is:

"Amplifiers will oscillate.  Oscillators won't."

I have experienced this myself on several occasions.   :palm:

And of course there is the old observation of the professors high up in their ivory towers who don't know which end of a soldering iron to hold.
Title: Re: When you follow the schematic but it doesn't work
Post by: b_force on July 25, 2018, 12:03:52 pm
Yes out of textbooks and as advised by the lecturers. It's almost as if they'd never built the things  :palm:

You will be surprised how many university professors have absolutely no idea on fields that he/she is not exactly working on (we are ARWU ECE subject ranked top 10 worldwide).

I once had a professor, teaching communication protocols, who has no idea what's differential signal and how it increases bandwidth. She only knows RS485 is faster than RS232, but has no idea why.

And I also had a professor, despite living in US for 2 decades, has no idea about American slang and English memes. She likes to eat salmon, and every time she pronounces like she likes to eat semen. And she always says she likes to "blow", of course it's something else.

Actually in our department, it's hard to find a computer engineering/network engineering professor who can read schematics, and a few EE professors who can code properly (not just grabbing crap from CodeProject or Arduino forum).

And I kid you not, we have DSP topic PhD students working on the latest imaging processing technology that has no idea how to compute a 2N point real FFT with an N point complex FFT.

Again, we have power electronics major PhD students who absolutely master control theory, but has no idea how to actually drive a MOSFET or how to design a current shunt amplifier.

And yes, we do have people who don't know ground clips are always tied together, as we did have expensive firework shows. And we do have people who can't f*ing solder.

Welcome to 2018, where everyone knows nothing at all about fields outside his/her exact field.
Can I vote you for president for almost every single school or university in the world?

When I was working for a company this drove us absolutely nuts.
Getting students or interns who can actually DO and KNOW something.
My boss at the time put it very well, "They train people to be very good and efficient in learning and making exams, not in broadening their views and understand the world around them"

What makes this story a little ironic and difficult is that there are quite some companies out there still judging someone by his level of graduation.
So even people who have an impressive CV are just being ignored when not having a certain formal level criteria.
Talking about wasting talent........

 
Title: Re: When you follow the schematic but it doesn't work
Post by: Kleinstein on July 25, 2018, 12:23:10 pm
Even with a relatively simple circuit things can get wrong, by having a wrong part or wrong polarity or just broken parts. Also misprints in circuit diagrams are rather common. From memory the Elektror journal had about 2-3 corrections to older circuits per issue.

High frequency circuits are especially tricky. However also simple looking circuit not meant to oscillate can do that if murphy helps with the layout. Modern transistors are quite fast and thus one may not even see it oscillate with a slow 20 MHz scope.

Finding faults in circuits (you own or just build after a schematics) is part of the fun.

I remember an amplifier that worked quite well as a radio receiver for a Russian language station. I never found out the frequency, as the normal radio I had could not get that station (e.g. outside the normal bands).
Title: Re: When you follow the schematic but it doesn't work
Post by: GeorgeOfTheJungle on July 25, 2018, 01:26:16 pm
I remember an amplifier that worked quite well as a radio receiver for a Russian language station. I never found out the frequency, as the normal radio I had could not get that station (e.g. outside the normal bands).

I once managed to do exactly that with a mixer :-) it had a few audio inputs, a few buffer opamps and CMOS analog switches, every now and then I could hear the radio :-). Had to put some low pass filters.
Title: Re: When you follow the schematic but it doesn't work
Post by: rsjsouza on July 25, 2018, 03:23:41 pm
You are quoting one extreme of the spectrum.  I am sure there are some amazing professors on the other extreme and a bunch of average in between.  Look for the world changing extreme, not the mediocre one.

I don't think so. Most of the time I see a person who knows all is an undergrad. The higher the education, the less the common ECE background knowledge one retains from BS education.

Most truly amazing Swiss knife engineers I've ever seen are either tinker/hobbyist on their own (learn by passion) or are just never received graduate education.
In my life I have seen examples in any direction. When I started in the university I had the same impression with some professors, but over the years I found out that the ones that lead or were part of research labs were quite close to the metal, as they suffered with lack of money and resources and needed to build and teach the students how to build most of the infrastructure to get further goals. Also, the lack of resources also meant we were using 50's and 60's equipment well into the 90's and they needed to explain to us how they actually worked so we could understand its limitations to do our job.

In these days I also learned something else: no formal education can trump passion. When I entered the university, there were three of us that had some experience with electronics and couldn't wait to reach the point where actual electricity/electronics lectures would start. The basic course seemed insurmountable (Calculus, Diff Eqns, Complex Math, Mechanics, etc.) but the big carrot after that phase certainly eased the pain, at least for us. Many others dropped out of the university before finishing the basic course. 

If someone is truly passionate about anything, the formal education will become what you make of it - all these weekends and evenings studying things that were apparently disconnected from my core passion (electronics) only helped me broaden my horizons.
Title: Re: When you follow the schematic but it doesn't work
Post by: b_force on July 25, 2018, 03:27:41 pm
Passion is indeed the most important thing of all.
The biggest key factor you're looking for as a company.
Title: Re: When you follow the schematic but it doesn't work
Post by: GeorgeOfTheJungle on July 25, 2018, 04:13:20 pm
They're teaching C# and nodejs at my local college and their staff have absolutely no fucking idea what they are doing. We have had a couple of their "graduates" in on trial and we're basically having to get them to unlearn a lot of stuff. I mean you don't write an OO program entirely in static methods ffs. But that's what they told us. Seriously, no.

Node.js was a very nice little project at the beginning, but it has grown many legs and arms, five or six eyes, and two noses and three ears => it's ugly now. It went nuts when Ryan Dahl, the BDFL, left.
Title: Re: When you follow the schematic but it doesn't work
Post by: bd139 on July 25, 2018, 04:29:34 pm
Yeah all the PHP holocaust perpetrators jumped on it then.

Now it’s “package manager of the hour” territory.
Title: Re: When you follow the schematic but it doesn't work
Post by: bd139 on July 25, 2018, 04:30:06 pm
Passion is indeed the most important thing of all.
The biggest key factor you're looking for as a company.

I know lots of passionate people who are fucking useless.
Title: Re: When you follow the schematic but it doesn't work
Post by: b_force on July 25, 2018, 04:55:35 pm
Passion is indeed the most important thing of all.
The biggest key factor you're looking for as a company.

I know lots of passionate people who are fucking useless.
Lol. Well there are also lots of people with a degree that are equally useless.
So i guess that's a draw.
Title: Re: When you follow the schematic but it doesn't work
Post by: GeorgeOfTheJungle on July 25, 2018, 05:04:57 pm
But he has a point, you surely also know many graduates that couldn't care less.
Title: Re: When you follow the schematic but it doesn't work
Post by: Buriedcode on July 25, 2018, 06:55:15 pm
Although I an generally quite cynical - and rarely positive, I have noticed most of this thread is pretty negative.  The op has mentioned fairly specific examples (analogue, oscillators) probably build on solderless breadboard that haven't worked, and then the replies are full of "most published circuits are useless!!".  And has even moved on to people claiming that students and professors don't know anything... this gives a very warped (and wrong) view of the world.  Any newbie reading this thread is just going to see a bunch of old timers complinaing about how things aren't the same these days and trying to put them off learning anything.  Maybe start another thread in general chat if you want a platform to whine.

I'll admit, the internet has a LOT of crap schematics that do a disservice to electronics education by perpetuating poor designs, or old designs like using the PIC16F84, or using LM324's for audio stuff.  But when I started electronics when I was about 11, I built plenty of circuits out of magazines (maplin, guitar effects from the web etc..) and most worked - despite me not really having a clue how.  That's more a testament to the designers of these circuits than my own (dodgy) prototyping. Some circuits are just more stable than others, and some require knowledge not only of how it works but also of the components used and their properties.  I suspect BJT oscillators are more annoying than say, 555 circuits.

If a circuit doesn't do as expected, its an excellent learning opportunity - something BD139 pointed out.  If one really doesn't know where to start, then that's what forums are for! (if we ignore the replies along the lines of "that's a bad circuit, try a different one").  Debugging and working out what does what is arguably a much more useful skill than just reading textbooks.
Title: Re: When you follow the schematic but it doesn't work
Post by: james_s on July 26, 2018, 04:17:48 am
A lot of my early projects didn't work. In retrospect it was usually a combination of trying to substitute parts I couldn't get (well before the internet era) and plain old fashioned wiring errors. I'm sure there were some poorly designed/improperly drawn circuits I found too but a lot of the failures were my fault, just a matter of being a kid without much experience building stuff.
Title: Re: When you follow the schematic but it doesn't work
Post by: Jwillis on July 26, 2018, 05:22:47 am
I find the internet is flooded with bogus schematics including a lot of simulations that don't work in reality. If the schematics include demonstrations and good documentation then it becomes a bit better but not always.You just have to sort though the pile of BS and experiment.After a while you can sometimes just look at a circuit and tell if it will work or not.It depends on experience.But you know learning is half the fun.It's a nice feeling in a eureka moment when one can say "OH I get it now!!"
Title: Re: When you follow the schematic but it doesn't work
Post by: tooki on July 26, 2018, 01:41:36 pm
Wow, I think a lot of you have totally unrealistic expectations!!

I once had a professor, teaching communication protocols, who has no idea what's differential signal and how it increases bandwidth. She only knows RS485 is faster than RS232, but has no idea why.
Why would they need to know?

And I also had a professor, despite living in US for 2 decades, has no idea about American slang and English memes. She likes to eat salmon, and every time she pronounces like she likes to eat semen. And she always says she likes to "blow", of course it's something else.
What’s your native language, blueskull?

I mean, I assume you know that in English, the L in salmon is silent.

What did she mean by blowing?  :o

Actually in our department, it's hard to find a computer engineering/network engineering professor who can read schematics, and a few EE professors who can code properly (not just grabbing crap from CodeProject or Arduino forum).
And why should they need to??

Welcome to 2018, where everyone knows nothing at all about fields outside his/her exact field.
It’s a necessity. The amount of total human knowledge is growing at an exponential rate. It’d be literally impossible to try and learn all the stuff outside your niche.



Coming from the IT domain on college level, I'm still wondering about the classic dual system apprenticeship in IT here in CH. Those guys spend 4 years education, normally 3,5 to 4 days per week in an IT company and the rest in business school. You might think, they learn some bloody basics about IT like simple transistor circuits, flipflops,, Ohms law or logics or even the essentials about how a cpu is working:

Just forget it!

There are no essentials, no basics taught anymore nowadays. It just counts, that they know to maintain a windows installation or maybe set up PC from the basic components - but how the components actually work - no way.
they know every detail about the main tasks their companys are in; about webdesign, programming, troubleshooting some particular software or whatsoever - but as soon as they're out of their well known playground, they are lost. It's a shame
(As a fan of the Swiss apprenticeship/dual system...) Why on earth should they waste time learning about flip flops and the inner working of CPUs? None of that is of even the tiniest use in the job they’re training for. A chef doesn’t need to know plumbing, they need to turn on the faucet and get water to cook with. 99% of programmers don’t need to know the inner workings of the hardware, so why on earth would non-programmer IT staff need it?!?!?!?

Would you rather they waste 2 years of their education learning stuff that has ZERO practical application, which would mean skipping even more stuff they DO need to know?

I think it also might be good for you to understand the difference between an academic education and learning a trade. The latter is not about knowing for the sake of it, it’s about preparing you to do a job.

P.S. The school component of an IT apprenticeship in CH isn’t at business school, it’s at a trade school.
Title: Re: When you follow the schematic but it doesn't work
Post by: bd139 on July 26, 2018, 02:00:27 pm
At this point, non programmer IT staff are dying. We actually have none and we have 120 IT staff. Automation is king. If you can't program what the fuck are you doing in IT? Seriously. And to program, you need to know the machine abstraction. It's programming 101.
Title: Re: When you follow the schematic but it doesn't work
Post by: Buriedcode on July 26, 2018, 02:42:08 pm
At this point, non programmer IT staff are dying. We actually have none and we have 120 IT staff. Automation is king. If you can't program what the fuck are you doing in IT? Seriously. And to program, you need to know the machine abstraction. It's programming 101.

What does that have to do with new players building circuits from schematics?
Title: Re: When you follow the schematic but it doesn't work
Post by: bd139 on July 26, 2018, 03:36:02 pm
Knowledge is a pyramid whatever you do.
Title: Re: When you follow the schematic but it doesn't work
Post by: Buriedcode on July 26, 2018, 04:08:32 pm
Knowledge is a pyramid whatever you do.

Which means what exactly?  Please stay on topic.  I fail to see how your view of your IT staff lacking in some way relates to newbies trouble-shooting circuits they built from sketchy sources.
Title: Re: When you follow the schematic but it doesn't work
Post by: tooki on July 26, 2018, 04:13:02 pm
At this point, non programmer IT staff are dying. We actually have none and we have 120 IT staff. Automation is king. If you can't program what the fuck are you doing in IT? Seriously. And to program, you need to know the machine abstraction. It's programming 101.
There's all sorts of non-programming IT. Hardware, business analysis, UX design, it goes on and on.

And no, for most programming, you don't need to know the machine abstraction in any great detail. That's literally the reason for having the abstraction.
Title: Re: When you follow the schematic but it doesn't work
Post by: tooki on July 26, 2018, 04:14:53 pm
I'm reminded of 2-3 times I tried to make a C-R oscillator w/ a BJT and maybe an op-amp once, and they never worked. I didn't try changing much, but it never worked. I bet the schematics were fine tho.

Then 1 utuber, an old radio guy, with proper schematics from an old book, I tried 2-3 little circuits and they never worked but his did. With those it was probably the BJT or JFET not being quite right, and not getting the loop gain right.



Don't you hate it tho when you follow a schematic and it doesn't work and you don't know why ? (time to re-try some)

It's just like recipes that don't work, because it turns out they weren't actually tested before publishing…  :wtf:

Title: Re: When you follow the schematic but it doesn't work
Post by: james_s on July 26, 2018, 04:44:23 pm
There's all sorts of non-programming IT. Hardware, business analysis, UX design, it goes on and on.

And no, for most programming, you don't need to know the machine abstraction in any great detail. That's literally the reason for having the abstraction.


Seems the trend in tech lately has been to hire programmers to do everything, product design, UI design, QA, it's probably why software quality has taken such a dive recently pretty much across the board. My first iPhone was rock solid, polished, slick UI, everything worked. The one I have now is very buggy, inconsistencies in the UI, reminders often fail to pop up or get out of sync between the lock screen and the reminder menu, even the built in apps crash. It's very obvious that parts of the UI were designed by people who have no business designing a UI, and there is no longer sufficient QA. This is only one example, I see it everywhere.

Programmers should be spending their time programming. Other positions should be filled by people with expertise in those areas. "IT" is not a one size fits all field, automation is not a replacement for professional QA, engineers tend to be lousy at UI design, and developers who like writing code better than working with people make lousy managers.
Title: Re: When you follow the schematic but it doesn't work
Post by: tooki on July 26, 2018, 05:01:22 pm
There's all sorts of non-programming IT. Hardware, business analysis, UX design, it goes on and on.

And no, for most programming, you don't need to know the machine abstraction in any great detail. That's literally the reason for having the abstraction.


Seems the trend in tech lately has been to hire programmers to do everything, product design, UI design, QA, it's probably why software quality has taken such a dive recently pretty much across the board. My first iPhone was rock solid, polished, slick UI, everything worked. The one I have now is very buggy, inconsistencies in the UI, reminders often fail to pop up or get out of sync between the lock screen and the reminder menu, even the built in apps crash. It's very obvious that parts of the UI were designed by people who have no business designing a UI, and there is no longer sufficient QA. This is only one example, I see it everywhere.
Hear, hear! In UX (my field), we call those "UX unicorns": people expected to do usability research, interaction design, graphic design, and coding. Sure, you can find people who "can" do all those things. But I'll be damned if I've ever seen one who can do all those things well!

As for quality: thank Agile for that. Agile itself is a reasonably sound methodology (not highly sound, just barely acceptable). But it's still a formal methodology. But tons of places say they're going "Agile", when in fact they're just going "free-for-all", with no formal test cycles, just devs pushing untested code to production… (I've worked in customer/tech support at a software company that did that. What a goddamned nightmare…)

Programmers should be spending their time programming. Other positions should be filled by people with expertise in those areas. "IT" is not a one size fits all field, automation is not a replacement for professional QA, engineers tend to be lousy at UI design, and developers who like writing code better than working with people make lousy managers.
Exactly. I think a lot of folks (even in IT!) assume that IT means programming, and that all areas of IT must include it, and that's just not true.
Title: Re: When you follow the schematic but it doesn't work
Post by: bd139 on July 26, 2018, 05:18:07 pm
Thats what everyone said until their job turned into three lines of python.  :-DD

I agree but the focus is on automation. The whole point is that if a task is to be done regularly then automation has a cost benefit. Even our analysts automate with specflow and our project management team automate their workflow with python. Our graphic designers automate their pipelines with various tools (I don’t go there myself). Our management team run automated reporting they built themselves. Our customer support team drive our public API to resolve issues with their own scripts. Our entire front to back end process stack is automated. All our marketing is data and code driven.

Everyone is a programmer if they like it or not. We destroyed all of our competitors because of automation.

We’re “a loose interpretation of agile” but continuous delivery focused. Everything from code to production is automated.
Title: Re: When you follow the schematic but it doesn't work
Post by: IanMacdonald on July 26, 2018, 05:21:29 pm
They're teaching C# and nodejs at my local college and their staff have absolutely no fucking idea what they are doing. We have had a couple of their "graduates" in on trial and we're basically having to get them to unlearn a lot of stuff. I mean you don't write an OO program entirely in static methods ffs. But that's what they told us. Seriously, no.

Colleges seem to have an obsession with OO programming. While it does have its uses, it's an extremely inefficient way of doing things. I also find it weird that they insist on using C, basically a stripped-down language designed to keep overheads to an absolute minimum on puny hardware, coupled to so heavyweight a paradigm. Kinda seems like two mutually defeating objectives, does it not? 

You have to ask whether it might not be better take the middle ground and use a less stripped-down procedural language.  :-//

That is even before you take into account the serious security issues of C.
Title: Re: When you follow the schematic but it doesn't work
Post by: bd139 on July 26, 2018, 05:51:19 pm
Not really. OO languages scale up to huge projects a lot better than non OO ones. I’ve never seen a large successful procedural or functional project. They all turn to shit way earlier.

I think you need to at least play with assembly, learn C, learn Java properly and learn a functional langauage properly. Then go and use whatever you feel fits the problem.
Title: Re: When you follow the schematic but it doesn't work
Post by: GeorgeOfTheJungle on July 26, 2018, 06:01:16 pm
Ryan Dahl is back, with a new node.js

https://github.com/ry/deno
https://youtu.be/M3BM9TB-8yA?t=1s

We start again from scratch!
Title: Re: When you follow the schematic but it doesn't work
Post by: bd139 on July 26, 2018, 06:53:38 pm
Can’t be arsed now :)
Title: Re: When you follow the schematic but it doesn't work
Post by: james_s on July 27, 2018, 03:09:25 am
Thats what everyone said until their job turned into three lines of python.  :-DD

I agree but the focus is on automation. The whole point is that if a task is to be done regularly then automation has a cost benefit. Even our analysts automate with specflow and our project management team automate their workflow with python. Our graphic designers automate their pipelines with various tools (I don’t go there myself). Our management team run automated reporting they built themselves. Our customer support team drive our public API to resolve issues with their own scripts. Our entire front to back end process stack is automated. All our marketing is data and code driven.

Everyone is a programmer if they like it or not. We destroyed all of our competitors because of automation.

We’re “a loose interpretation of agile” but continuous delivery focused. Everything from code to production is automated.

Automation is ideal for regression testing, but the automation code is never going to see something interesting and deviate from the testing it has been programmed to do in order to track down some other issue. Automation is almost mandatory as a part of software development, but it is not a replacement for professional testers, it augments existing testing and reduces the need to test the same basic functionality over and over on each new build. Far too many companies try to do ALL of their testing with automation and product quality suffers. Most software is garbage these days, the mentality has become ship it now, fix it "later", except that later never comes and a lot of issues don't get fixed or with each fixed issue comes a bunch of new features and new issues. My iPhone is a shining example of this, the old one I had with iOS6 was fantastic and polished, the one I have now with iOS10 is crap in terms of quality. It's buggy and feels half baked, the UI is full of inconsistencies, the reminders fail to pop up frequently or get out of sync with the lock screen, apps crash, even the native ones. It's blatantly obvious that there was insufficient QA and frankly for a company like Apple that is unacceptable. They built their reputation on products that were slick and polished, to an OCD-like level.
Title: Re: When you follow the schematic but it doesn't work
Post by: tooki on July 27, 2018, 09:02:44 am
And to automate something, you have to define it. And that takes someone. And you just can’t automate requirements engineering, design, or architecture.
Title: Re: When you follow the schematic but it doesn't work
Post by: GeorgeOfTheJungle on July 27, 2018, 09:14:51 am
When all you've touched is the code for A there's no need to test B...  >:D
Title: Re: When you follow the schematic but it doesn't work
Post by: GeorgeOfTheJungle on July 27, 2018, 09:35:47 am
Can’t be arsed now :)
You're not exactly a node fanboy, right? Don't like callbacks and CPS or what?
Title: Re: When you follow the schematic but it doesn't work
Post by: Alex Nikitin on July 27, 2018, 09:40:26 am
When you follow the schematic but it doesn't work ?

Now we all know the answer: you become a programmer "software engineer" :-DD .

Cheers

Alex
Title: Re: When you follow the schematic but it doesn't work
Post by: bd139 on July 27, 2018, 09:45:18 am
Can’t be arsed now :)
You're not exactly a node fanboy, right? Don't like callbacks and CPS or what?

I have no problem with CPS. Hell I wrote my own scheme implementation littered with continuation passing  and tail recursion and all that faff years ago.

It’s just JavaScript. It’s like being in charge of shaving the devil’s nut sack.
Title: Re: When you follow the schematic but it doesn't work
Post by: GeorgeOfTheJungle on July 27, 2018, 09:57:11 am
It's a cute little language.
Title: Re: When you follow the schematic but it doesn't work
Post by: bd139 on July 27, 2018, 10:05:21 am
Cute like an angry alligator with a crack pipe.
Title: Re: When you follow the schematic but it doesn't work
Post by: GeorgeOfTheJungle on July 27, 2018, 10:12:44 am
ƒ()(); love it!
Title: Re: When you follow the schematic but it doesn't work
Post by: b_force on July 27, 2018, 11:41:38 pm
Thats what everyone said until their job turned into three lines of python.  :-DD

I agree but the focus is on automation. The whole point is that if a task is to be done regularly then automation has a cost benefit. Even our analysts automate with specflow and our project management team automate their workflow with python. Our graphic designers automate their pipelines with various tools (I don’t go there myself). Our management team run automated reporting they built themselves. Our customer support team drive our public API to resolve issues with their own scripts. Our entire front to back end process stack is automated. All our marketing is data and code driven.

Everyone is a programmer if they like it or not. We destroyed all of our competitors because of automation.

We’re “a loose interpretation of agile” but continuous delivery focused. Everything from code to production is automated.
To get a little bit back on topic, this is exactly why most schematics don't work.
PCB and analog design (I call analog everything else that's more than just 1s and 0s = non-lineair behaviour) doesn't seem to be relevant anymore these days.

The majority of vacancies I see is all about programming. In fact best is finding someone who is able to be a top notch programming, FPGA programmer and also has plenty of experience in PCB design.
Mostly all asked and noticed in just one sentence.
I really don't like to put people into boxes, but many of these things are an expertise on its own.
Just simply by the fact that it takes so much time and effort to master one of these skills that you don't have much capacity to master another one.
On the other hand, it looks like that people aren't respected anymore if they don't know 100% of the ins and outs.

This is also what's immediately wrong with most schematics online.
For someone having some kind of experience in board design and putting it all together, you can already see that a lot of times it's just simply asking for trouble.
People seem to forget that we don;t live in an ideal world an we will never be, hooray physics.
Title: Re: When you follow the schematic but it doesn't work
Post by: tooki on July 29, 2018, 01:00:54 am
Why would they need to know?

Innovation and research without knowing the underlying physics is like building structures without a solid base.
I can't see why the "bubble economy" risk doesn't apply to engineering as well.
I disagree, it depends entirely on the field. A software engineer doesn't benefit in any way, shape, or form from understanding the physics of the electronics that run their code.


What’s your native language, blueskull?

The vast difference between Chinese and English is not an excuse for me not to polish my English skill.
No, certainly not! Nor did I mean to suggest that your English is subpar (it's excellent, as far as I can tell from your writing.) I was just curious because it would give me a better image of your language background. (See next Q.)

I mean, I assume you know that in English, the L in salmon is silent.

Still, it's far from "see-men".
Yes, but the reason I asked about your native language is that one's native language not only informs how we speak other languages, but also how we hear them. (Like how many English speakers mishear the German "ch" as the "sh" sound.)

(I studied linguistics as my minor at university, aside from being a polyglot myself.)

What did she mean by blowing?  :o

A (likely electrical) load.
I hope the parentheses are true. Cuz blowing a non-electrical load is also… a thing. ;)


And why should they need to??

We are a research university, not a tech school. We are supposed to train people with a general, good and comprehensive understanding in the field(s) and expand body of human knowledge.

I don't expect details, but I would expect at least, for an ECE professor, to be able to explain roughly what a "hello world" does under the hood, down to transistor level.
I think even ECE is so broad that expecting that from everyone is absolutely unreasonable.


It’s a necessity. The amount of total human knowledge is growing at an exponential rate. It’d be literally impossible to try and learn all the stuff outside your niche.

No need to be "all". But a general understanding of everything related to the circle one travels is not too much to ask for.
Yes, but I doth declare that I suspect your meaning of a "general understanding" is far, far deeper than is realistic.