EEVBlog, the CNET of test equipment! - Page 1
Forum section: electronics / general

author: olsenn
author_rank: Frequent Contributor
timestamp: July 18, 2012, 11:00:11 pm
content: Okay, so first off I love the videos/forum. However, I do feel that there is an abundance of teardowns and reviews of equipment, talk about equipment, suggestions about equipment... equipment, equipment, equipment. Occasionally there is some VERY basic theory/info thrown out, like ohm's law and how to use a LM317 and how to read a datasheet etc, but I don't see a lot of info on how to make a tesla coil or how to build a step-up converted from discrete components (not premade IC's), or even basic engineering skills like how to use an op-amp in a non-inverting configuration or RC/RL/RLC filters...I guess this site feels like the CNET of test equipment. Great for finding teardowns and reviews of equipment, but not much info on how to use that equipment for something practical. I'd like to see more math and theory, even more videos like the one about making the soft power switch, that explains some basic transistor theory, and shows how to use that theory to solve a real world problem.That's it for my rant; I still love the blog!

author: EEVblog
author_rank: Unknown
timestamp: July 19, 2012, 12:19:00 am
content: You don't see tesla coils because I have little interest tesla coils.You don't see discrete component DC-DC because I little interest in discrete component DC-DC.You don't see advanced math because I have little interest in advanced math.You see a lot of test gear and reading datasheets because I like test gear and reading datasheets.Also, people seem to like it...I hope you see a pattern forming here...The blog can't possibly be all things to all people, it's just not possible.Dave.

author: KTP
author_rank: Frequent Contributor
timestamp: July 19, 2012, 12:35:43 am
content: I have recently seen makerbots and arducopters on EEVblog, neither of which have anything to do with test equipment.Dave does like Back to the Future, so I hope to see a flux capacitor teardown soon. Every time I go into Radio Shack and the salesperson asks if they can help me, I ask for one....no stock yet.

author: Chet T16
author_rank: Frequent Contributor
timestamp: July 19, 2012, 12:47:50 am
content: Quote from: EEVblog on July 19, 2012, 12:19:00 amGiven this pattern, i have a simple question...Do you have an interest in boobs?

author: free_electron
author_rank: Super Contributor
timestamp: July 19, 2012, 12:50:30 am
content: Those are hard to tear down .... except if they are gel-filled. Puncture those and they go pfwwwwrrrrrttttttt...

author: dda
author_rank: Contributor
timestamp: July 19, 2012, 01:23:43 am
content: Quote from: free_electron on July 19, 2012, 12:50:30 amDave does have a proven interest in farting novelty toys....

author: olsenn
author_rank: Frequent Contributor
timestamp: July 19, 2012, 02:02:44 am
content: I didn't mean to offend you Dave, I just thought I'd add a suggestion to the 'suggestions' thread on your forum... geesh.Furthermore, I'm not just talking about you and your vidoes, I'm referring to posts on the forum as well; I'm not telling anyone what to post, and I'm not even asking anyone what to post, I'm just putting it out there that it is something I would like to see. There have been several good ones on here recently, not lmited to circuitry for debouncing switches, transistor calculations, batteries in parallel etc, and I love them. If you look at my previous posts, you'll see that I have provided reviews and have done teardowns of test gear as well; I'm not opposed to it, I'm just saying it's nice to switch it up every now and again.Hope this clears up any confusion!

author: EEVblog
author_rank: Unknown
timestamp: July 19, 2012, 04:33:30 am
content: Quote from: olsenn on July 19, 2012, 02:02:44 amNo offense taken at all.Just trying to explain why you don't see "this and that" on the blog, because I've gotten this question hundreds of times.But as always, feedback taken on board about what people want to see.QuoteThe forum is exactly what you make of it.If you don't see topics that interest you, then start them yourself and get people talking about it.Have you seen the excellent power supply design threads for example?Or various descriptions (Free Electron's one come to mind) of how transistors work at the atomic and process level for example?There is a ton of deep technical info on here you may not find at first glance.Dave.

author: ivan747
author_rank: Super Contributor
timestamp: July 20, 2012, 12:44:33 am
content: Novelty toys...

author: sorin
author_rank: Frequent Contributor
timestamp: July 20, 2012, 03:19:22 am
content: I agree with "olsen"The last good video what I remember about electronic design is : episode #90you do teardown of thousand $ instruments, and circuit design for beginners, this dont match sens for meps. This is just my opinion

author: EEVblog
author_rank: Unknown
timestamp: July 20, 2012, 03:58:44 am
content: Quote from: sorin on July 20, 2012, 03:19:22 amI have come to learn that doing advanced electronics design stuff is:a) not nearly as easyb) not nearly as popularPeople love the teardowns. If they didn't I probably wouldn't be doing them as much, or at all any more.By far, the most requests I get is for beginner stuff, like in the order of 99%.Dave.

author: Galenbo
author_rank: Super Contributor
timestamp: July 20, 2012, 01:34:15 pm
content: Quote from: Chet T16 on July 19, 2012, 12:47:50 amI'm sure he is, you may have noticed he's also a fitness instructor.

author: saturation
author_rank: Super Contributor
timestamp: July 20, 2012, 04:05:53 pm
content: Nearly every electronics forum provides design advice.However, in my over 20 years being online, including 10 more years in pre-Internet 1980s BBS days, then CompuServe and AOL forums, not one forum discussed or tore down gear consistently and thoroughly as eevblog. Test gear is of interest to everyone, from experts to novices, but experienced people appreciate them far more.Its a great niche, and keeps knowledgeable people coming back to the forum, which helps provides a large pool of experts.

author: free_electron
author_rank: Super Contributor
timestamp: July 20, 2012, 05:43:49 pm
content: One thing i miss a bit in the teardowns is some depth beyond 'taking the screws out' ...it should be a bit more than just some pretty pictures. and pointing at a rectifier and heatsink. Try to hghilight why a specific part is chosen in a specific application and then give some background info on parts selection.you could talk for hours on selecting something as simple as a resisitor. capacitors could take days to explain ....If tearing down equipment where manuals are avaliable : tear down the schematic also ! highlight interesting techniques for example.The detailed teardown with explanations of a simple supply like a E3410 could teach a lot to beginning people. It is full of clever little things. ( and we'd get out of the stage where people a re limited to lm317 power supplies becasue anything more than that confuses the heck out of them, or scare them)Teardowns i liked : the marconi signal generator , the power supply that fried a cople of days ago , the agilent multimeter U12xx .Teardowns with mixed feelings : the RLC meter based on two integrated circuits.. nothing to be learned from those. its a black box with zero documentation. viewers are still none the wiser on how an RLC bridge really works.Teardowns i didn't like : the photocopier .... its just a bunch of plastic and metal with some optosensors and a massive control board of which you can learn nothing. Granted, there is the laser deflector. that's kinda cool. but only for 1 minute. its a motor with a mirror.. there is some things missing... like how the motor stays in sync with the projected data , ho the drum also needs to advance in sync to do the next line , how the rasterizer software needs to compensate for the angular distortion when projecting the image. those are the interesting bits..I'm working on two detailed teardowns ( pictures , i'm not a very camera-guy ) of equipment with technical background information. One of em is a real RLC bridge. Agilent style ...I guess i want to see more things like what i did in my post on the inner workings of the E3632 power supply (the trickery with analog sample hold, the dac , the measuring principle, the linear optocouplers trick , etc ) and the 34401 multimeters multislope convertor . Most people know only the comparator based converters (lm3914 style : chain of comparaotrs with voltage dividers) , or a SAR (dac with comparator) , some a sigma delta (simple principle very difficult to make) .But slope convertors ? unknown , even though it is one of the oldest converters ( and most used convertors ) almost everyone raises eyebrows.. and when you tell them ICL7106 they all nod. yeah we have used that chip... well ... that's a slope convertor. ever read the datasheet ? (sheepischly .. no.. we only wired the display to it and use as is ... )Those are the interesting bits. Just pointing at a chip i not really a 'learning moment'. it's still fun to watch. But you don't really learn anything from it.Granted some 'magic' these days is deeply hidden. like the PFANG. cool to take a look inside. the only 'learning moments' would have been to reverse engineer one of the power supply blocks , highlight the usage of multi parallel ceramic caps to lower ESR and to take a peek at the analog output stage ... which sits under a metal shield.What is going on under the big heatsink and the attached memories will remain a mystery only revealed to those that designed the chip and machine. So that's less of interest.just my two cents.ps. i too like to look inside stuff so don't get me wrong and don;t stop doing that.

author: saturation
author_rank: Super Contributor
timestamp: July 20, 2012, 07:30:29 pm
content: ... you are right free_electron, I haven't had a chance to comment, but your tear downs are fantastic. But if we look at the service manual of old HP gear as example of ideal tear downs, with detailed theory of operation, schematics and photographs of key boards, each tear down could become a huge book, not to mention the time it takes to put this together.What I see is an executive summary of the equipment; key operational areas, and if nothing can be deciphered [ such as programmable devices, since so much is in the firmware] degree of integration and build quality. With older discrete and old analog gear you can 'guestimate' what's going on by the layout of the parts. Tear downs, IMHO, is an overall picture of build quality, and less a reverse engineering feat.Quote from: free_electron on July 20, 2012, 05:43:49 pm

author: free_electron
author_rank: Super Contributor
timestamp: July 20, 2012, 08:10:08 pm
content: True , you could not covere every detail , but at least a few ( one or two ) should be explored in a bit more depth ...And it doesnt necessarily need to be schematics related.take the power supply that conked ut for example. at one point the control board is removed and we notice 'white residue'. that;s flux residue .. and we move on.Have a 5 minute talk about solder flux and flux remover. what do you use , when do you use , how do you cleanup and why ? some flux is conductive some hygroscopic some corrosive.. now that would be informal. You'd walk away, not only with a cool instrument teardown, but also with a bit of practical advice that you can immediately apply the next time you make a board or solder something. You had entertainment AND you learned something.I don;t know how widely this is going to be known but, when i grew up there was a very populare cartoon series called 'Il etait une fois' ( was translated in several different languages 'once upon a time' ) produced by Albert Barillé.They had multiple series. : Once upon a time : Mankind , Space, Life , America , The inventors , The Explorers , Earth .. and so onmultiple epoisodes with a story arc. always revolving around the same people. it was very entertaining and you learned a bunch of things from them ( as kid )EEvblog could be an 'engineers' version of that. ( Dave could be Maestro )I don't know how widely spread this series was but it ran for at least 15 years in europe and canada ( Procidis was the maker and canadian i believe )Maestro is the 'old guy with the long white beard. actually he looks more like captain caveman. all you see is a walking white beard with two eyes and two sprigs of long hear poking out on top...

author: Chasm
author_rank: Regular Contributor
timestamp: July 20, 2012, 11:46:44 pm
content: Ah, I know thatseries, saw it quite a lot as a kid. Definitely one of the better educational series.I also didn't like the copier teardown too much. There were a few glaring errors, very obvious to anyone who has been volunteered to support one of them in a office.At least Dave noticed, in the end, that this is indeed not an analog machine.

author: EEVblog
author_rank: Unknown
timestamp: July 21, 2012, 03:15:03 am
content: Quote from: free_electron on July 20, 2012, 05:43:49 pmDone videos on both, yes they can go for hours!QuoteI've done a video on how LCR measurement works.Maybe should be linked in.QuoteSure, but how long do you want these videos to be? And how much effort can I afford to expend doing them?And it can be argued that they can be entirely separate things.Teardowns can just be teardowns highlighting the construction and system design etc. An actual design operation of a product can be (and maybe should be?) separate videos.Not all people want to sit through design stuff, they just want to see the guts, and vice-versa.You can kinda combine the two in a flashy quick kinda way they do on the EngineerGuy videos for example, but detailed talk on anything requires a lot of time and effort.Add up how many hours you'll spend on those photo/forum text teardowns, and multiply by ten for videoDave.

author: EEVblog
author_rank: Unknown
timestamp: July 21, 2012, 03:21:40 am
content: Quote from: free_electron on July 20, 2012, 08:10:08 pmAnd a classic example that would be better off with it's own video.If only so you don't have to explain it time and time again in each teardown, and can link to a specific video, instead of 21:40 into this video...And to keep the teardown video as short as possible of course, they are already long enough.And of course then you get complaints about why you didn't talk about this and that in-depth as wellThere is always a huge balance of what to include/exclude, and what to discuss in brief/detail in each video, be a teardown, review, or something else.Unfortunately it's a balance where you can never really win and satisfy everyone.Dave.

author: EEVblog
author_rank: Unknown
timestamp: July 21, 2012, 03:24:35 am
content: Quote from: Chasm on July 20, 2012, 11:46:44 pmSuch is the life of an off-the-cuff video blogger. I can't be an expert in all things.And I'm not sure what anyone with any advanced knowledge of photocopiers would want to watch the teardown for anyway!Dave.

author: free_electron
author_rank: Super Contributor
timestamp: July 21, 2012, 03:53:32 am
content: hmm you got some good point.how about this : ever seen the "mysterious cities of gold" ? 20 minutes of animation followed by a 5 minute documentary.That could be a format. Do the teardown as usual. Last 5 minutes ( it don't need to be more than that ) are spend on a particularity discovered during the teardown that is good to know and applicable to many things.The last 5 minutes are saved as a mini-fact show. so a teardown topic would have 2 links. the teardown and the 'addendum'. The addendum could be collected in its own index."dave's no-nonsense good-to-know mini-tips" (DNNGTKMT's)just my 2 cent's. It's your show after all

author: vk6zgo
author_rank: Super Contributor
timestamp: July 22, 2012, 06:51:00 am
content: Back in the day,when we had such things as "Cadet Engineers",young "ginger beers" were dragged out of their academiccomfort zones,& sent out into the field,where they could see how things were actually put together in their chosen industry.After all, a piece of Electronic equipment is not just an abstraction on paper,or a computer screen,it is a solid,three dimensional "thing" which has to be usable in the real world.They would find out the proper ways of doing the various mechanical things which need doing to make the final product viable.Unfortunately,many EE (& Technical) students don't get this exposure any more,so Dave's teardowns have value,even if all you take away from them is an awareness of proper methods of assembly, industry standards of quality, & testing,etc.

author: sorin
author_rank: Frequent Contributor
timestamp: July 22, 2012, 07:12:40 am
content: Quote from: EEVblog on July 21, 2012, 03:15:03 amDid you refer to "EEVblog #38"If yes...Sorry but you say us a simple principle that anyone that have do the high school already know.the LCR measurement theory is not so simple, it's also includes the Interpolation that's is a little complicated.

author: neotesla
author_rank: Unknown
timestamp: July 30, 2012, 09:33:25 am
content: Those are some advanced high schools you've got there bro.