EEVblog Electronics Community Forum

EEVblog => EEVblog Specific => Topic started by: EEVblog on June 22, 2017, 07:02:28 am

Title: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: EEVblog on June 22, 2017, 07:02:28 am
As the title says, kinda...
Dave answers the age old question, do single take videos really work?
No. No, they don't.

https://www.youtube.com/watch?v=-IOmRGjVELU (https://www.youtube.com/watch?v=-IOmRGjVELU)

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 charger

I challenge anyone to sit through all 15 minutes of Meredith Perry's talk on being a "technology innovator", go on, I dare you...
https://www.youtube.com/watch?v=ukgnU2aXM2c (https://www.youtube.com/watch?v=ukgnU2aXM2c)

Ultrasonic exposure limits:
https://www.researchgate.net/publication/235923211_A_review_of_current_airborne_ultrasound_exposure_limits (https://www.researchgate.net/publication/235923211_A_review_of_current_airborne_ultrasound_exposure_limits)

Zener Diodes Tutorial: https://www.youtube.com/watch?v=O0ifJ4oVdG4 (https://www.youtube.com/watch?v=O0ifJ4oVdG4)

Paul Reynold's blog (Former vice president of Engineering at uBeam):
http://liesandstartuppr.blogspot.com.au (http://liesandstartuppr.blogspot.com.au)
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: BravoV on June 22, 2017, 07:06:36 am
Congratulation Dave !  :clap:

Tutorial on turning two NPN transistors into a fast bidirectional zener impulse clamp.

How is this compared to bi-directional TVS ?
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: EEVblog on June 22, 2017, 07:12:37 am
How is this compared to bi-directional TVS ?

Much cheaper but not as higher impulse power.
Don't know about further specifics off-hand.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: daqq on June 22, 2017, 07:39:33 am
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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Brumby on June 22, 2017, 07:51:24 am
You took Dave's challenge too literally.  I took it as a warning....


Congratulations Dave!

Can't wait for the next 1,000!!
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: McBryce on June 22, 2017, 08:06:07 am
Congratulations!

Now tell us more about those EEVBlog labelled differential probes that were on the bench during the transistor as a zener experiment!!!  :o

McBryce.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: bktemp on June 22, 2017, 08:08:25 am
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 (http://www.edn.com/electronics-blogs/designing-ideas/4311721/Bob-Pease-on-bounding-and-clamping-techniques)


Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: tszaboo on June 22, 2017, 08:45:14 am
Congratulations Dave!

(https://fciwypsc.files.wordpress.com/2014/07/dilbert.gif?w=460)

Though I would say Meredith Perry is not worthy to be in this video.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: kultakala on June 22, 2017, 08:50:38 am
Congratz to the 1000 ! :)

I have to agree to NANDBlog about Meredith Perry!   :palm:
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: AndersJ on June 22, 2017, 08:55:38 am
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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: igendel on June 22, 2017, 09:17:17 am
I challenge anyone to sit through all 15 minutes of Meredith Perry's talk on being a "technology innovator", go on, I dare you...

Watching the part you put in your video was more than enough :-DD

Such 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?

:palm:

Oh yeah, and congratulations on the 1000th video!  :)
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Dr. Frank on June 22, 2017, 10:09:03 am
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
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: daqq on June 22, 2017, 10:10:35 am
Quote
and that "experts" should not be trusted further than you can throw them.
Yes, 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).
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: ElektroQuark on June 22, 2017, 10:36:05 am
1000.
Now comes the good part...
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: JPortici on June 22, 2017, 10:45:42 am
i want the superhero plaque :D
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Gromitt on June 22, 2017, 10:51:51 am
i want the superhero plaque :D

http://www.boldport.club/shop/product/165025514 (http://www.boldport.club/shop/product/165025514)
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: G0HZU on June 22, 2017, 11:41:02 am
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 further than you can throw them.

Yes, 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...  ;)

Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: G0HZU on June 22, 2017, 12:14:20 pm
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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: FrankBuss on June 22, 2017, 12:44:39 pm
Yes, 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.

That'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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Brumby on June 22, 2017, 12:56:00 pm
.... and looks like she despises all engineers and experts.

Yet she aspires to deliver a product that works on those same principles that the engineers and experts already understand.

 :palm:
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: X on June 22, 2017, 12:57:33 pm
How to really be a technology innovator
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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Kjelt on June 22, 2017, 01:01:49 pm
Congrats Dave on the millenium post.  :-+

Tedtalk  :palm:
Quote
"as a non expert I had an advantage because I could look at a problem from different angles because I just did not know it was possible"
Four 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/Theranos (https://en.wikipedia.org/wiki/Theranos)

Then 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 year
https://www.cbinsights.com/blog/startup-failure-post-mortem/ (https://www.cbinsights.com/blog/startup-failure-post-mortem/)
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: madires on June 22, 2017, 01:17:46 pm
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! ;D
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Raj on June 22, 2017, 02:12:57 pm
zena as transistor he said, you wont find in a textbook he said :popcorn:
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: HighVoltage on June 22, 2017, 03:42:40 pm
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
 
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: oldway on June 22, 2017, 04:10:02 pm
My sincere congratulations for these 1000 (even more) interesting and wonderful videos. :clap:
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: gildasd on June 22, 2017, 04:28:21 pm
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...
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: RGB255_0_0 on June 22, 2017, 05:02:34 pm
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  :-+
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Arjan Emm on June 22, 2017, 05:47:43 pm
nicely done dave. A good bit of all the different sort of videos you do.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: exe on June 22, 2017, 06:01:33 pm
Congratulations!


Good video, I love it.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Fungus on June 22, 2017, 08:22:59 pm
I actually used some BJTs as diodes the other day at Arduino club.

Everyone was really impressed by my encyclopedic knowledge!   :-DD

I enjoyed seeing the Keysights and Insteks doing really badly in the noise test.  :popcorn:

PS: Thanks for all the videos! I've learned a lot, even got jobs thanks to stuff I learned here.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: rsjsouza on June 22, 2017, 09:02:36 pm
Dave, congratulations on the "officially named" 1000th video (you actually posted many more). It was very entertaining!
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Brumby on June 23, 2017, 02:20:45 am
Engineering wise, isn't video 1024 far more relevant?

Engineering 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 the subset of 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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: EEVblog on June 23, 2017, 05:12:41 am
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.

I really only had a couple of minutes to show something on those 11 scopes, so options are rather limited.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: SL4P on June 23, 2017, 07:09:57 am
Dave - Did you really shoot the workshop segments at 6am++, or is the BTTF clock 12-hour without am/pm indication !
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Fungus on June 23, 2017, 08:15:41 am
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 further than you can throw them.

Yes, 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.

Yep. 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")!

Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: G0HZU on June 23, 2017, 09:27:35 am
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 further than you can throw them.

Yes, 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.

Yep. 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")!

I'd like to nominate Fungus for the 'strawman argument of the month' award please :)
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Kjelt on June 23, 2017, 10:05:30 am
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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Kjelt on June 23, 2017, 10:08:40 am
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 ?

Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: EEVblog on June 23, 2017, 10:48:36 am
Congrats Dave on the millenium post.  :-+

Tedtalk  :palm:
Quote
"as a non expert I had an advantage because I could look at a problem from different angles because I just did not know it was possible"
Four years later she still does not know it is not possible or is she continuing because of loss of face ?

It's got to be latter.
She simply must know 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, with her), 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 interviews

Now 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.

She needs to 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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: madires on June 23, 2017, 10:51:49 am
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.

There's also the Dunning–Kruger effect. A "basic understanding" might become dangerous >:D
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: EEVblog on June 23, 2017, 10:53:01 am
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.

But 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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Fungus on June 23, 2017, 11:16:28 am
Sure there is a possibility that an expert can be hindered by his knowledge.

An "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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: RGB255_0_0 on June 23, 2017, 11:33:29 am
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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Kjelt on June 23, 2017, 12:37:16 pm
There's also the Dunning–Kruger effect. A "basic understanding" might become dangerous >:D 
Well 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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: tszaboo on June 23, 2017, 01:50:51 pm
Now 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.
How 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?
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Fungus on June 23, 2017, 02:09:57 pm
It always bothered me: Where does the money from all these failing startups go?

There's stuff on youtube with Meredith riding the vomit comet, having lunch with Bono, etc.

Where do they waste all those money? Does it just end in their pocket?

Yep. 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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: nctnico on June 23, 2017, 02:11:36 pm
Hiring engineers is more expensive than factory workers. Besides that money will be spend on lawyers and patents.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: nixfu on June 23, 2017, 04:18:32 pm
Nice Job.

#1000 was epic.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: StillTrying on June 23, 2017, 05:55:17 pm
There's stuff on youtube with Meredith riding the vomit comet

That'll be from when she worked for NASA.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: 3db on June 24, 2017, 07:26:07 am
zena as transistor he said, you wont find in a textbook he said :popcorn:

That circuit has absolutely nothing to do with what Dave was describing.  :palm:
3DB
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: joeqsmith on June 24, 2017, 02:11:30 pm
zena as transistor he said, you wont find in a textbook he said :popcorn:

That circuit has absolutely nothing to do with what Dave was describing.  :palm:
3DB

My guess is Dave was thinking about the 121GW when making that segment. 
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: oldway on June 24, 2017, 02:28:06 pm
As aficionado of high end analog oscilloscopes, I would like to thanks Dave for the use of the excellent HP1740A in his 1000 video... :-+
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: jonovid on June 24, 2017, 03:34:08 pm
zena as transistor he said, you wont find in a textbook he said :popcorn:

That circuit has absolutely nothing to do with what Dave was describing.  :palm:
3DB

My guess is Dave was thinking about the 121GW when making that segment. 

Zener Diodes Tutorial   repurposing semiconductors  :-/O  got to love it
reminds me of a trick of using logic gates for analogue   ;D
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: SeanB on June 24, 2017, 07:14:10 pm
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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Brumby on June 24, 2017, 11:25:03 pm
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.

That 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.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: Circlotron on June 25, 2017, 12:10:54 am
Meredith Perry makes even Clock Boy look like an engineer.
Title: Re: EEVblog #1000 - Fundamental Mailbag Retro Teardown Shootouts are Bullshit
Post by: f4eru on June 25, 2017, 08:40:34 pm
Yep.
Burning Investor money : OK
Transmitting power through sound: OK
Increasing distance, and adding focusing through phased arrays : OK
Adding a localization possibility (probably by TOF triangulation on elements of the array, of with array scanning and probing - A kind of sonar.): OK
Increasing power to levels where even the air is non linear : No way to 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