EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: June 22, 2017, 07:02:28 am
content: As the title says, kinda...Dave answers the age old question, do single take videos really work?No. No, they don't.SPOILERS:Tutorial on turning two NPN transistors into a fast bidirectional zener impulse clamp.A comparison of the low level signal noise on 11 different oscilloscopes.Teardown of the CH7 analog TV 300W RF Power amplifier.Debunking of the uBeam ultrasonic wireless power phone chargerI challenge anyone to sit through all 15 minutes of Meredith Perry's talk on being a "technology innovator", go on, I dare you...Ultrasonic exposure limits:https://www.researchgate.net/publication/235923211_A_review_of_current_airborne_ultrasound_exposure_limitsZener Diodes Tutorial:Paul Reynold's blog (Former vice president of Engineering at uBeam):http://liesandstartuppr.blogspot.com.au

author: BravoV
author_rank: Super Contributor
timestamp: June 22, 2017, 07:06:36 am
content: Congratulation Dave !Quote from: EEVblog on June 22, 2017, 07:02:28 amHow is this compared to bi-directional TVS ?

author: EEVblog
author_rank: Unknown
timestamp: June 22, 2017, 07:12:37 am
content: Quote from: BravoV on June 22, 2017, 07:06:36 amMuch cheaper but not as higher impulse power.Don't know about further specifics off-hand.

author: daqq
author_rank: Super Contributor
timestamp: June 22, 2017, 07:39:33 am
content: Congratulations to the 1000th video Dave.I have watched the TED talks video. Now I have a twitch in the eye that's not going away any time soon.

author: Brumby
author_rank: Unknown
timestamp: June 22, 2017, 07:51:24 am
content: You took Dave's challenge too literally. I took it as a warning....Congratulations Dave!Can't wait for the next 1,000!!

author: McBryce
author_rank: Super Contributor
timestamp: June 22, 2017, 08:06:07 am
content: Congratulations!Now tell us more about those EEVBlog labelled differential probes that were on the bench during the transistor as a zener experiment!!!McBryce.

author: bktemp
author_rank: Super Contributor
timestamp: June 22, 2017, 08:08:25 am
content: Great video! Thanks for the teardown of the TV transmitter amplifier. I was waiting for this since you got it but did only teardown the modulator.You could easily do a sperate video for each segment going more into detail.Exceeding the base-emitter reverse breakdown voltage does not only turn a BJT into a zener/avalanche diode, but also into a LED!If you have a transistor in a metal can package, cut it open and apply a couple of mA in reverse direction (~10mA for small signal transistors, ~100mA for something like 2N3055) and you will see a pale yellow light coming from the area between base and emitter.Here is an article written by Bob Pease on clamping (using transistors as zener diodes):http://www.edn.com/electronics-blogs/designing-ideas/4311721/Bob-Pease-on-bounding-and-clamping-techniques

author: tszaboo
author_rank: Super Contributor
timestamp: June 22, 2017, 08:45:14 am
content: Congratulations Dave!Though I would say Meredith Perry is not worthy to be in this video.

author: kultakala
author_rank: Regular Contributor
timestamp: June 22, 2017, 08:50:38 am
content: Congratz to the 1000 !I have to agree to NANDBlog about Meredith Perry!

author: AndersJ
author_rank: Frequent Contributor
timestamp: June 22, 2017, 08:55:38 am
content: Perhaps her message is not primarily whether the energy transfer concept will work or not,but,instead to not give up just because someone dislikes your idea,and that "experts" should not be trusted farther than you can throw them.

author: igendel
author_rank: Frequent Contributor
timestamp: June 22, 2017, 09:17:17 am
content: Quote from: EEVblog on June 22, 2017, 07:02:28 amWatching the part you put in your video was more than enoughSuch sound advice on innovation and success will surely put universities and all those useless professionals out of business. If I want to get anywhere in life, I better get rid of all my programming and electronics books, fast. And that "to think outside the box" idea... simply amazing, how did she ever come up with that original analogy?Oh yeah, and congratulations on the 1000th video!

author: Dr. Frank
author_rank: Super Contributor
timestamp: June 22, 2017, 10:09:03 am
content: Dave,congratulation for your 1000th video!It is very dynamic and entertaining, so I have high expectations for the future, as displayed in the first scene.Frank

author: daqq
author_rank: Super Contributor
timestamp: June 22, 2017, 10:10:35 am
content: QuoteYes, I can see how humanity might greatly benefit from ignoring the opinions, calculations, research and facts provided by people with experience (engineers, experts). They should be instead publicly mocked and presented as, at best, useful tools for people with The Vision (the oompa loompas of visionaries).

author: ElektroQuark
author_rank: Unknown
timestamp: June 22, 2017, 10:36:05 am
content: 1000.Now comes the good part...

author: JPortici
author_rank: Super Contributor
timestamp: June 22, 2017, 10:45:42 am
content: i want the superhero plaque

author: Gromitt
author_rank: Regular Contributor
timestamp: June 22, 2017, 10:51:51 am
content: Quote from: JPortici on June 22, 2017, 10:45:42 amhttp://www.boldport.club/shop/product/165025514

author: G0HZU
author_rank: Super Contributor
timestamp: June 22, 2017, 11:41:02 am
content: Quote from: AndersJ on June 22, 2017, 08:55:38 amYes, I agree. I thought the general message that engineers and experts are often blinkered in their thinking was absolutely spot on. Also, being naïve in one's approach can sometimes give a person an advantage compared to someone else who has been conditioned to reach (premature) conclusions through formal training. The other powerful message is 'don't give up' on innovation if you get a few knockbacks.I'm basing my thoughts on having spent my entire career working in engineering labs exposed to people from all levels of expertise. Sometimes even the top experts can be horribly wrong and it gets worse if you get a group of them who agree with each other.Some of the (many) keyboard/google experts to be found on internet forums will probably argue that the experts/engineers in question aren't competent in some way. But if the experts/engineers knew everything then there wouldn't be anything left to invent...

author: G0HZU
author_rank: Super Contributor
timestamp: June 22, 2017, 12:14:20 pm
content: I suppose the other obvious point that should be made is that some of the greatest scientific discoveries were achieved via mistakes or accidents. i.e. the scientist/engineer/inventor looked to solve one problem but actually found a novel solution to something else by accident.

author: FrankBuss
author_rank: Unknown
timestamp: June 22, 2017, 12:44:39 pm
content: Quote from: G0HZU on June 22, 2017, 11:41:02 amThat's true and it was not bad for the first some minutes of the talk, except I got somehow the feeling that she thinks all engineers are having asperger. The last half of the video was just annoying. She is so full of herself and looks like she despises all engineers and experts.

author: Brumby
author_rank: Unknown
timestamp: June 22, 2017, 12:56:00 pm
content: Quote from: FrankBuss on June 22, 2017, 12:44:39 pmYet she aspires to deliver a product that works on those same principles that the engineers and experts already understand.

author: X
author_rank: Regular Contributor
timestamp: June 22, 2017, 12:57:33 pm
content: How toreallybe a technology innovatorInvent a problem that doesn't actually exist.Conjure up a convoluted solution that doesn't exist for the problem that doesn't exist. Don't forget to include wireless, smart, internet-connected technology just because you can. Also make sure you copy Apple's design process as badly as possible.Look pretty and talk to gullible investors. Tell everybody how engineers and experts are limited in their thinking by virtue of being brainwashed by evil spirits or something, and how you are the pinnacle of innovation, and how you are the only person in the universe who thinks outside the box.Finish off by stating that we always need to advance our technology and we are heading into the future.Go to step 1.Occasionally engineers might be blinkered in their thinking, but when they find a real problem, they are surprisingly good at solving it practically, unlike "technology innovators" and "technical design innovation specialists" and whatever head-up-the-arse titles these "people-people" can come up with.

author: Kjelt
author_rank: Super Contributor
timestamp: June 22, 2017, 01:01:49 pm
content: Congrats Dave on the millenium post.TedtalkQuoteFour years later she still does not know it is not possible or is she continuing because of loss of face ?Reminds me of this blood testing startup from Elizabeth Holmes, 18 yrs when she founded Theranos.Worth billions when tests concluded it was fishy and it dropped to zero in a week.https://en.wikipedia.org/wiki/TheranosThen 60kHz? How about dogs, bats and other animals that will go bat-crazy when bombarded with this kind of noise ?Oh well for every succesfull startup, hundreds if not thousands fail, take a look at the list for only this yearhttps://www.cbinsights.com/blog/startup-failure-post-mortem/

author: madires
author_rank: Super Contributor
timestamp: June 22, 2017, 01:17:46 pm
content: I think we shouldn't applaud Dave with precipitate haste before performing QC on another 1000 videos or so. It's all about statistics, you know!

author: Raj
author_rank: Frequent Contributor
timestamp: June 22, 2017, 02:12:57 pm
content: zena as transistor he said, you wont find in a textbook he said

author: HighVoltage
author_rank: Super Contributor
timestamp: June 22, 2017, 03:42:40 pm
content: Congratulations, Dave !You have been very entertaining and had many great subjects in your 1000 videos!Even my wife likes to watch your mailbag videos with me, and normally she is not in to technical videos at all. She tells me that you have a very good and interesting way of presenting.Keep going for the next 1000!And a big thank you for making this great forum available to all of us.All the best to you from northern Germany

author: oldway
author_rank: Super Contributor
timestamp: June 22, 2017, 04:10:02 pm
content: My sincere congratulations for these 1000 (even more) interesting and wonderful videos.

author: gildasd
author_rank: Frequent Contributor
timestamp: June 22, 2017, 04:28:21 pm
content: Engineering wise, isn't video 1024 far more relevant?If every one is considered a bit of Dave, then that will equal 128 Bytes of knowledge.And you can go to the Moon with 1.13687e-13 Pebibytes...

author: RGB255_0_0
author_rank: Frequent Contributor
timestamp: June 22, 2017, 05:02:34 pm
content: I was excited by the IG post where you showed all the scopes, thinking you'd do a shootout where you'd spend the time because of the special circumstances being #1000. I was slightly disappointed but enjoyed the video.Congratulations Dave

author: Arjan Emm
author_rank: Regular Contributor
timestamp: June 22, 2017, 05:47:43 pm
content: nicely done dave. A good bit of all the different sort of videos you do.

author: exe
author_rank: Unknown
timestamp: June 22, 2017, 06:01:33 pm
content: Congratulations!Good video, I love it.

author: Fungus
author_rank: Super Contributor
timestamp: June 22, 2017, 08:22:59 pm
content: I actually used some BJTs as diodes the other day at Arduino club.Everyone was really impressed by my encyclopedic knowledge!I enjoyed seeing the Keysights and Insteks doing really badly in the noise test.PS: Thanks for all the videos! I've learned a lot, even got jobs thanks to stuff I learned here.

author: rsjsouza
author_rank: Super Contributor
timestamp: June 22, 2017, 09:02:36 pm
content: Dave, congratulations on the "officially named" 1000th video (you actually posted many more). It was very entertaining!

author: Brumby
author_rank: Unknown
timestamp: June 23, 2017, 02:20:45 am
content: Quote from: gildasd on June 22, 2017, 04:28:21 pmEngineering wise, 1000 is more appropriate. It's 10 raised to a power which is a multiple of 3.The only time 1024 comes into the picture is when you take thesubsetof engineering that relates to binary circuits. If Dave's channel was a computer one, then you would have a stronger argument - but it's much broader than that.

author: EEVblog
author_rank: Unknown
timestamp: June 23, 2017, 05:12:41 am
content: Quote from: RGB255_0_0 on June 22, 2017, 05:02:34 pmI really only had a couple of minutes to show something on those 11 scopes, so options are rather limited.

author: SL4P
author_rank: Super Contributor
timestamp: June 23, 2017, 07:09:57 am
content: Dave - Did you really shoot the workshop segments at 6am++, or is the BTTF clock 12-hour without am/pm indication !

author: Fungus
author_rank: Super Contributor
timestamp: June 23, 2017, 08:15:41 am
content: Quote from: G0HZU on June 22, 2017, 11:41:02 amYep. Ohms law is only for linear-thinking pussies. There's ways around it if you have enough imagination.Flying faster than light? That's easy! All you have to do is imagine it (and google for "rocket ship")!

author: G0HZU
author_rank: Super Contributor
timestamp: June 23, 2017, 09:27:35 am
content: Quote from: Fungus on June 23, 2017, 08:15:41 amI'd like to nominate Fungus for the 'strawman argument of the month' award please

author: Kjelt
author_rank: Super Contributor
timestamp: June 23, 2017, 10:05:30 am
content: I think Fungus has a good point.Sure there is a possibility that an expert can be hindered by his knowledge.IMO the risk is way higher that a non expert tries to do something trivial that is over and over proven non-feasible like a pepetuum mobile.I think Daves examples of SolarRoadWays and now this 2% efficient ultrasonic charger startups proof that you at least need some basic understanding and knowledge of the matter before you can become succesfull.

author: Kjelt
author_rank: Super Contributor
timestamp: June 23, 2017, 10:08:40 am
content: Or to add to re-invent something that has already been invented long ago.How many patent applications get rejected because there is prior art and the person has not even taken the time to do a decent patent search ?

author: EEVblog
author_rank: Unknown
timestamp: June 23, 2017, 10:48:36 am
content: Quote from: Kjelt on June 22, 2017, 01:01:49 pmIt's got to be latter.She simplymustknow that it can't work as intended.It's been 5 years, 10's of millions of dollars, she had the best ultrasound experts in the world working for her (sorry,withher), and all she has to show for it is a huge brick with hobby level tracking technology that charges a phone under ideal conditions at the most hideous efficiency and expense.The desperation in her voice of trying to justify it away that they have "won" the critic war is clear in the latest interviewsNow almost everyone has left (all of the experts have), she has literally a huge new building that is empty, and her former VP of engineering is publicly ripping her a new one on why it will never work. She knows the end game now, but her only option will be to persevere until it all goes tits-up or the investors are finally able to throw her out and sell what's left of the tech and/or pivot it.Sheneedsto be either proven right (won't happen of course), or she needs to go down trying so she can blame everything and everyone but the stupidity of the entire concept.

author: madires
author_rank: Super Contributor
timestamp: June 23, 2017, 10:51:49 am
content: Quote from: Kjelt on June 23, 2017, 10:05:30 amThere's also the Dunning–Kruger effect. A "basic understanding" might become dangerous

author: EEVblog
author_rank: Unknown
timestamp: June 23, 2017, 10:53:01 am
content: Quote from: Kjelt on June 23, 2017, 10:05:30 amBut she was "successful". She shot to fame over the last 5 years, got lauded around under the banner of "genius" and was even called "the next Elon Musk", and got to spend near $30M of other people's money whilst still retaining a ton of ownership and all the power.She'll be able to milk that forever, even when this thing fails.

author: Fungus
author_rank: Super Contributor
timestamp: June 23, 2017, 11:16:28 am
content: Quote from: Kjelt on June 23, 2017, 10:05:30 amAn "expert" in ultrasonics will be able to tell you the efficiency of this to several decimal places.A non-expert can see the problem of size and having to hold just right.An idiot can see that Qi is 1000000% better.

author: RGB255_0_0
author_rank: Frequent Contributor
timestamp: June 23, 2017, 11:33:29 am
content: Sticking a Qi charge within the stadia seating would be more beneficial, though I wouldn't sit on my $800.But I get the impression uBeam and other wireless charging technologies that are doomed before the second pint of Guinness was that they are supposed to work over a longer distance than 1-2cm.

author: Kjelt
author_rank: Super Contributor
timestamp: June 23, 2017, 12:37:16 pm
content: Quote from: madires on June 23, 2017, 10:51:49 amWell I myself try to stay away as much as possible from psychology and their findings.The last 6 years more "proven" psychology experiments and studies (even from the 80s and 90s that build careers) are now being found worthless and wrong because they fail miserable in tests that try to repeat their outcomes.More fraude has been committed in this field than any other and they are only re-testing the tip of the iceberg.That is probably why psychology is not and never will be a real science.

author: tszaboo
author_rank: Super Contributor
timestamp: June 23, 2017, 01:50:51 pm
content: Quote from: EEVblog on June 23, 2017, 10:48:36 amHow does this work? You make a startup, have an average idea, raise millions of VC money. That 30M would pay ~10 expert with 250.000 salary for 3 years. Renting , prototypes, equipment, another few million. There is 10-20 million left.It always bothered me: Where does the money from all these failing startups go? I just cannot imagine it. For 30M, in a traditional business, you can create jobs for ~100 people, and a self sustaining company. Those are the numbers that I'm seeing for investments from big firms into factories.Where do they waste all those money? Does it just end in their pocket?

author: Fungus
author_rank: Super Contributor
timestamp: June 23, 2017, 02:09:57 pm
content: Quote from: NANDBlog on June 23, 2017, 01:50:51 pmThere's stuff on youtube with Meredith riding the vomit comet, having lunch with Bono, etc.Quote from: NANDBlog on June 23, 2017, 01:50:51 pmYep. New cars, first class flights to give Ted talks, expensive hotels, etc. can get rid of millions of $$$ in a matter of months (if you let them). And with nothing to show for it.Hell, one trip to Vegas can do that and you don't even have to gamble, just tick the "front row seats and VIP everything" box.

author: nctnico
author_rank: Super Contributor
timestamp: June 23, 2017, 02:11:36 pm
content: Hiring engineers is more expensive than factory workers. Besides that money will be spend on lawyers and patents.

author: nixfu
author_rank: Unknown
timestamp: June 23, 2017, 04:18:32 pm
content: Nice Job.#1000 was epic.

author: StillTrying
author_rank: Super Contributor
timestamp: June 23, 2017, 05:55:17 pm
content: Quote from: Fungus on June 23, 2017, 02:09:57 pmThat'll be from when she worked for NASA.

author: 3db
author_rank: Frequent Contributor
timestamp: June 24, 2017, 07:26:07 am
content: Quote from: Raj on June 22, 2017, 02:12:57 pmThat circuit has absolutely nothing to do with what Dave was describing.3DB

author: joeqsmith
author_rank: Super Contributor
timestamp: June 24, 2017, 02:11:30 pm
content: Quote from: 3db on June 24, 2017, 07:26:07 amMy guess is Dave was thinking about the 121GW when making that segment.

author: oldway
author_rank: Super Contributor
timestamp: June 24, 2017, 02:28:06 pm
content: As aficionado of high end analog oscilloscopes, I would like to thanks Dave for the use of the excellent HP1740A in his 1000 video...

author: jonovid
author_rank: Super Contributor
timestamp: June 24, 2017, 03:34:08 pm
content: Quote from: joeqsmith on June 24, 2017, 02:11:30 pmZener Diodes Tutorial repurposing semiconductorsgot to love itreminds me of a trick of using logic gates for analogue

author: SeanB
author_rank: Super Contributor
timestamp: June 24, 2017, 07:14:10 pm
content: Using a bipolar transistor as a zener is also a good way to make a nice wideband analogue noise source. Cheap noise source with a reasonable white spectrum, and could be filtered to make pink or other noise types, Just needed some good small signal wide bandwidth amplifiers as well to make RF noise as well.

author: Brumby
author_rank: Unknown
timestamp: June 24, 2017, 11:25:03 pm
content: Quote from: SeanB on June 24, 2017, 07:14:10 pmThat would make an interesting circuit to show someone unfamiliar with the idea. Watch them wonder what the two transistors are doing at the input of a wideband RF amp.

author: Circlotron
author_rank: Super Contributor
timestamp: June 25, 2017, 12:10:54 am
content: Meredith Perry makes even Clock Boy look like an engineer.

author: f4eru
author_rank: Super Contributor
timestamp: June 25, 2017, 08:40:34 pm
content: Yep.Burning Investor money :OKTransmitting power through sound:OKIncreasing distance, and adding focusing through phased arrays :OKAdding a localization possibility (probably by TOF triangulation on elements of the array, of with array scanning and probing - A kind of sonar.):OKIncreasing power to levels where even the air is non linear :No wayto give that into the hands of a customer. Not safe.Arguing it locates the phone to focus the energy to it and not damage your body ?No Way.Functional safety does not work without proved guarantee.Accepting 99% loss ?No Way.(50 million phone chargers * 500W loss -> 25 GW equivalent to 20 brand new nuclear plants generating waste)User accepting the limitations in orientation and free line of sight requirements ?No Way.Trying to compete with that crazy expensive double phased array bricks setup against two flat 30 cent copper coils :No way.Conclusion : It won't happen. You can't just ignore physics, ergonomics, Safety, and economics and also make a successful product