#308

[@danielvrolijk9272]

I am studying for my a&p. Your videos are EXTREMELY helpful to me. Not too long and not doesn’t dive too deep. I am also an amateur radio operator!(Extra class)

[@Ratkill]

Am I the only one who feels like I should be paying for this? I've got a pile of books that aren't half as informative. The value of these videos can't be overstated. Thank you so much.

[@w2aew]

You can donate to my channel if you'd like, but certainly not necessary!

[@stargazer7644]

@@w2aew How would one donate to your channel?

[@w2aew]

@@stargazer7644 there is a donate link on the main channel page, under the About tab.

[@VoidHalo]

It's very layered, as well. I've found I can watch any one of these videos say, 6 times over the course of 3 years and still find something new (or something old I forgot) that I've learned from it. Not only that, but as your understanding of electronics gets better over the years, so too does your ability to notice new things in these videos. So, it's beneficial on many different levels for both newbs and veterans alike. Personally, I enjoy these as much now as I did when I was only a year into electronics.

[@ErikS-]

Awesome analog equipment!

[@davidkilpatrick1640]

Any video featuring the 576 is always worth a watch 👍🏼

[@GopalSao-e3w]

Lovely demo respected sir

[@rrangana11]

Good you have included links and references to your other videos about Diodes. I have seen your all Diode, they are very highly valuable resources.

[@FiveEars]

My first w2aew video: I'm more than a little impressed with your work. With pdf notes! I was going to ask if they were available even before the video ended. And all the cross-referenced links! Lots of learning on tap. Thank you. Super work. I subscribed and smashed that bell ;-)

[@AB-yu2tj]

Enjoyed it? Hell yeah. Couldn't think of anything better to do on a Saturday night but to go through some Diode videos while waiting for the lamb stew simmering on the stove. I'm running very impatient right now. I'm going to go to video 82

[@jcampbell2481]

Another excellent video! I have finally worked my way through all of your videos. I have now viewed all 308 videos, and enjoyed them very much. 73

[@w2aew]

WOW! That is quite an accomplishment, and a time commitment! Thank you for faith in my work!

[@BrendaEM]

I wanted to write and say thank you for all of the electronics videos. The are consistently good. Thank you. Though, I've noticed that many of the electronics youtube channels I watch are run by amateur radio operators. So, I've been studying for my Technician and General licenses. For a job prospect, I've also spent about 40 hours, going through almost every signal integrity and TDR video LeCroy and R&S has. I likely won't get the job, so I might as well study a little more and get a amateur radio license, while I am almost there.

[@w2aew]

Good luck with your studying, and with your job prospecting!

[@tinkmarshino]

Darn son.. you make me feel smart! I can follow exactly what you are saying in these video's even though I just started to teach myself this stuff.. (Plus the fact that I am 67 and it takes some time to penetrate the old 60's detritus of my used brain cells) I truly appreciate all of your hard work to put these videos out! You have clear and concise teaching skills.. carry on, have fun and be safe!

[@johannesparkmann3899]

Best diode video on youtube

[@AECRADIO1]

Always cover the basics, and good course to revisit time and again. People forget simple formulas when not using them very often.

[@jimyohe100]

Excellent instructional video ... once again!

[@VoidHalo]

So much great information in this. And the links in the description are gold. I'm gonna have to bookmark this video just so I can come back to the links. One topic I was thinking might be good for this channel is why you shouldn't use an op amp as a comparator, or in any open loop configuration. I just read a great ap note from TI the other day about it and it seems to be something even seasoned veterans are guilty of doing. The paper was called Op Amp and Comparators - Don't Confuse Them! SLOA067. I really like the new format with the tablet, too. I like to take notes and copy what you've written down as I watch the video, but in the older ones it wasn't as easy because you would rarely have the whole page visible in one shot. The tablet solves that very nicely. Thanks for making these. I really appreciate it.

[@DeeegerD]

Nice to see another of your instructional videos. Always learn something new. Thank you.

[@Justplast]

Love your Teaching. Thank You for your time.

[@chillidogkev]

Fabulous video Alan, stuffed full of information and presented in the way only you can. Thanks. P. S. The cross check to previous videos was a great move.

[@Amperekaefer]

*Vielen Dank* für dieses interessante Video! Best regards, Roger, Schweiz

[@mahatmadoo2566]

So many types of diodes. There will probably be one in my coffee cup tomorrow morning, forward biased no doubt.

[@Farmelle]

Are you sure that's not just a straw?

[@troutrou0]

Thanks for yet another lovely video...I agree with the other commenter about the curve tracer, this model is pure Tek porn, I wish I can afford one one day. I was only slightly frustrated because I was expecting that at some point in this Tek porn, you would increase the sensitivity on the X axis to better show the dynamic forward resistance, and do a quick calculation of it, to illustrate this particular point. Other than that... excellent teaching video as always, it's like a drug, I can never have enough of them....but I understand it takes time to prepare them, obviously..... Your channel is now well over 100k and growing, so clearly people acknowledge the quality of your teaching, so keep them coming ! :-)

[@gonebamboo4116]

Great! I was just going to make a comment about links for the different types and there they are in the description. Thank you so much.

[@spiderjuice9874]

I like this style of video, very informative.

[@rene-jeanmercier6517]

Thank you so much for sharing your knowledge. It is ALWAYS a great pleasure for me when I see a KZbin pop-up of a video coking from you.

[@andymouse]

Excellent tutorial...cheers.

[@BryanByTheSea]

As usual another excellent informative tutorial. Please keep them coming.

[@sasines]

Great video and refresher. Thanks for doing these.

[@Radiowild]

Super explanation of the different diode characteristics. Good seeing you at the "swapfest"!

[@DefekCs]

Thank You a lot! Your channel is one of very few in KZbin I activated a bell icon. :)

[@electronic7979]

Very helpful video 👍

[@gerhardgroenewald6560]

Great idea with the reference videos. I will definitely use this video in the future with the reference videos as my diode toolbox. Alan you are the man!

[@troypelton563]

Love the "Back to Basics" series videos, great info as always. Ty.

[@ruhnet]

I've had this on my watch list since you posted it and finally got a chance to watch! Good stuff as always. 73s

[@SKARTHIKSELVAN]

Thanks for making video about basics.

[@TheRadioShop]

Thanks for the tutorial Alan

[@dpneber]

You'd think I wouldn't get excited to see another video about diodes after the tenth time you post one. This series should be called, "Down the Rabbit Hole: Diodes. Why So Many?"

[@hamradio323]

Another great video super clear explanation, thank you!

[@robertcalkjr.8325]

Thanks Alan! That is a very nice lesson on diodes!

[@Justplast]

Very Very Good Explanation.

[@ozosman3234]

Hi Alan. I'm now retired but have really become interested in electronics, especially in analogue audio equipment. I enjoy your videos and have now got to grips with the very basics, such as the relationship between voltage, current and resistance. I am writing to ask, which back to basics videos of yours should i be looking at first, so i can ( hopefully ) progress in an orderly manner with my knowledge of this exciting subject. Wishing you all the best from here in the U.K.

[@w2aew]

Probably best to look at the index file (www.qsl.net/w2aew/youtube/W2AEW_video_index.pdf) on page 10 where all of the Basics videos are listed. Pick-n-choose the topics that are fuzzy...

[@philprice4324]

@@w2aew Thanks for link Alan. The one posted didnt work but found this one; www.google.com/url?sa=t&source=web&rct=j&url=www.qsl.net/w2aew/youtube/W2AEW_video_index.pdf&ved=2ahUKEwji7rWB5tHlAhUJT30KHYHJALwQFjAMegQIAhAB&usg=AOvVaw38s20Xjd-WU9aAW_X1tiTq

[@gervaiscurrie6675]

great stuff - very clearly explained. - thx.

[@ahmatrizki5154]

great explaination,....

[@stephanc7192]

I love the B to B series!

[@johnbedell2376]

Thank you for doing this - very much appreciated.

[@DhammaChakkhu921]

Thank you very much for the video.

[@gearstil]

Thank you for the video!

[@grahambambrook313]

Alan, I recently managed to resurrect / resuscitate an old Tek 7403 oscilloscope that I was given - a long job but that's another story. It came with 3 plugins, one of which is a 7A22 differential amplifier module. At the moment, I cannot think what it can do for me and wondered whether you could do a (short?) video on function and possible uses /reasons for keeping it. I must stress, I am (was) a mechanical engineer and am dabbling with electronics in my retirement. Many thanks for all of your excellent videos - you do have a knack of explaining things in simple terms.

[@w2aew]

You might want to take a look at my video on differential probes to get an idea of what differential measurements are all about. This plug-in will give you very good sensitivity, much better than a normal single-ended vertical amp.

[@grahambambrook313]

@@w2aew OK will do, Alan, thanks - but I reserve the right to come back if it raises more questions than it answers. :-)

[@rrangana11]

Thanks for this video.

[@Axelvad]

Thank You.

[@曹永飞]

Think you very much! Good Job!

[@MattyJ66]

Thank you for the great video. Very much appreciate your efforts.

[@luismorgado9055]

You are a master.

[@tamaseduard5145]

nice job sir 👍 Thank you 🙏

[@jimomertz]

Life is like a diode - you can only go forward. You can’t go back.

[@Teqnyq]

What if it's a zener

[@lucimorgenstern5582]

@Teqnyq : Mind. Blown. 😜 #ZenerLife

[@Teqnyq]

@@lucimorgenstern5582 just deep questions and thoughts 😎

[@mosiotv]

Great one Alan 👍 tysm 🌷

[@coloradowilderness3139]

At last , back with basic

[@lidarman2]

Nice classic test equipment you have.

[@eclecticneophyte2581]

Nicely done. Perhaps someday you could also cover how diodes can be used for 'square law' detection (like for measuring the output of a homebrew RF amp)?

[@j.jorgoni6935]

Hi Mr. Wolke heartily i suggest you to make a series of videos in making some linear regulated bench power supplies with current limitation, which we can study and build, I wish you all the best

[@andrewferg8737]

Great video as always! Thanks again for educating us. I was wondering if you have any videos on active noise cancellation or "noise gating" using diodes...? or if you could point me in the right direction...

[@smartdesignengineering]

all of your videos are awesome. Please make a video on how to make a dmx controller.

[@saarike]

Really nice!

[@ChiefMade]

Your teaching is terrific!! I can’t seem to find anything on upgrading transistors in rf applications. Do you have a video on this or is it possible you could cover this subject?? Possible drop in replacements and upgrading with other components in circuit. Thank you

[@w2aew]

That's a complicated topic. In order to substitute/upgrade transistors in RF applications, you'd have to understand what particular parameters of the device in question (transition frequency, device capacitance, transit time, switching speed, etc.) is important for that specific application. There is no "rule of thumb" for this.

[@magiclay]

there is a zone on the diode curve that is not temp. dependent?

[@TheRogerx3]

OMG My inner nerd is so satisfied.... links :)

[@tseckwr3783]

How could you?? Using that nice wireless probe as a pointer?

[@grhinson]

Ha Ha, wireless probe...

[@1959Berre]

Because he can! :)

[@w2aew]

...a fitting use for a probe that got killed by a lab chair's wheel.

[@tseckwr3783]

@@w2aew Yikes!! I must say, I plead guilty to snapping off the tip. Fortunately, TEK made them replaceable.

[@billsmith396]

What kind of tablet are you using to present your presentation?

[@HenryYong]

Bill Smith wondering the same! Edit: I think it is "remarkable" paper tablet

[@vincei4252]

remarkable.com/ I really, really wanted one but the fact it requires "cloud" did it in for me. Your mileage may vary.

[@sipa2123]

@@vincei4252 good news, it doesn't require cloud. You get root access to the thing out of the box, and can set up eg. github.com/simonschllng/rm-sync, and backup 'wherever'

[@vincei4252]

@@sipa2123 cool. Thanks for the info.

[@waynegram8907]

It's common to put a capacitor across in parallel on LED optocouplers To cut down on the ticking noises. I'm not sure why a capacitor would help cut down the ticking noises that LED optocouplers but I'm guessing the capacitor smooths out the led optocouplers switching edges?

[@michaeltempsch5282]

While there are no ideal diodes, one can build a circuit that does a very close approximation. Often used in solar power applications to minimize losses between panel[s] and the controller.

[@power-max]

If you are talking about the active MOSFET based ones with a charge pump, I would say they should not even be called "diodes". The one from TI has to turn off periodically for the charge pump to recharge its internal storage cap to continue working. It creates a pulse train. Another one I have seen on bigclives channel in a SMPS also has odd limitations, where you cannot suddenly switch polarity without a brief period of no current.

[@bixy9347]

Thanks 🙏

[@walterbunn280]

So... weird question... which diode do you think has the most inherent band width? Like if you're going to be building a transceiver, which diode type is likely to be the most versatile in terms of circuit topology? You can always change the components in your circuit to adjust your filtering, which hopefully changes what signal is getting processed through your circuit, but using a particular diode that can be used to process an array of signals not uncommon. That said, it might be caused by bulk pricing discounts of electronic manufacturers than any real virtue of the diodes themselves. I kinda think Schotcky diodes probably have the highest inherent bandwidth to them because of their "leeky" nature, but they probably need alot of filtering in order to make them good detectors in low to mid-frequency applications.

[@w2aew]

It really depends on the application. For RF switching, PIN diodes are best because of the long recovery time. But, for mixing applications, schottkys are probably best. So, there is no universal answer.

[@gordonwedman3179]

Thanks for the review Alan. I made a screen shot of your list and will work my way through them. If anyone wants to see a discussion about an unusual "diode" take a look at DiodeGoneWild's latest video on a synchronous rectifier diode. Interesting beast.

[@waynegram8907]

Diodes can be used for Decoupling when bussing wire lines. In computer keyboards they use Diodes called Isolating Diodes for the matrix columns and rows to prevent "anti ghosting". I'm not sure why they have to use diodes to prevent anti ghosting. The diodes are used to Decouple the columns wires from the row wires. It would be nice if you made a video lesson about anti ghosting examples and diodes being used to Decouple applications examples.

[@EdwinNoorlander]

What kind of e-reader are you using? It’s nice.

[@w2aew]

It is an E-Ink writing tablet from www.remarkable.com

[@EdwinNoorlander]

w2aew thanks for your quick response. Greetings from the Netherlands.

[@waynegram8907]

I'm not sure if I'm correct about this because Diodes Depletion layer has more Doping material so it can Block the current when reversed bias? the Depletion layer in diodes and transistors has a lot of Doping materials? The current flows through the solid silicon crystals but if there is NO doping material the Silicon is just an insulator so not current will flow through the diode or transistor.

[@1828fernando]

Basic... but GREAT!!!! thanks!!!

[@boxingday11]

Thanks.

[@billwilliams6338]

w2aew, can you make a back to basics video about the oscilloscopes "add mode and subtractive mode". I'm not sure when I would want to add two waveforms together or when I would want to subtract two waveforms together for testing and troubleshooting boards.

[@w2aew]

I did, 7 years ago. kzbin.info/www/bejne/sKTcXqOupct1atE

[@JonathanKayne]

Could you do a video on operational transconductance amplifiers (OTA's)?

[@nraynaud]

I would like to add this for beginners: LEDs often can't really be used to block the backwards current because their peak reverse voltage is often quite low. So they really are just an annoying to use lamp.

[@w2aew]

... but a lot more efficient ...

[@yoramstein]

That display of yours - is it a book reader with the possibility of presenting scanned notes?

[@w2aew]

it is from www.remarkable.com

[@yoramstein]

Thanks and happy new year with lots of interesting circuits and new videos.

[@AltayBrusan]

Why when to zenner diodes are placed back to back they pass current? at least one of them is back biased and it does not let any electric field to pass through. so it act as an open circuit and the other diode should not receive any voltage. thanks for your great contributions.

[@w2aew]

When connected that way, they will conduct when the voltage applied exceeds the forward voltage of the one diode plus the zener voltage of the other.

[@jackallen6261]

Do you have any videos explaining the difference between an oscilloscope and a curve tracer? Very good video! and i just subbed. Thanks!

[@w2aew]

I don't, but can give you a brief overview here. Other than having a graphical display, the two are quite different. An oscilloscope is a general purpose *measurement only* system, to display signal variations (mainly voltage) vs. time. An oscilloscope does not provide any stimulus to a circuit or device under test, so is mainly used on devices that are powered up an operating. A curve tracer is a stimulus and measurement system. It applies voltage or current to a device under test and displays the response to that stimulus. It is typically used on devices that are not powered up.

[@jackallen6261]

@@w2aew OH okay, Thanks so much for the information! I have an old Hitachi scope I use on guitar tube amps and stereo amps for troubleshooting. I am a beginner tube amp (and the occasional radio) repair guy that doesn't really deal with solid-state circuits much at all, point to point wired tube stuff is my friend, lol. But I would love to learn more about solid-state discrete electronics. Thanks for the reply!

[@neilsheldon8355]

Hi Alan, ... Have you ever done a Video on different logic families? ... For Instance, TTL, CMOS, Schottky, LSTTL, Hi Speed Schottky TTL (If there is anything like that), Hi Speed CMOS, and all those before (RTL, etc), in between (EECL?) and following? Today, it's got to be a confusing world of logic families for those newer to the Logic families than myself, and even today, I'm sometimes confused, and could use a refresher. But one of the biggest reasons that we want to buy a quality O'Scope today is to be able to view these circuits. Can you help us sort it all out? Thanks ... 73 & DX!, Neil, K7WK

[@w2aew]

Nope, not yet - no videos on the myriad of logic families... (I'm mainly an analog guy, admittedly).

[@Radplus]

Hi In some logic ic outputs there is some unwanted negative short pulses after falling edge that can damage the microcontrollers inputs.. what circuit can block them can diode be used for this??

[@w2aew]

A Schottky diode can be used to limit the negative swing to a few hundred mV as long as the source is somewhat current limited.

[@Radplus]

@@w2aew whats the name of circuit that i can make with schottky diode in this case ??? is that clamping diode circuit????

[@cameraguy4767]

Thanks for using analog test gear. :-)

[@w2aew]

Yeah, more "intuitive" than watching numbers roll up or down..

[@xeno8555]

that'd be awesome if you could cover the use of accumulator resonators cells like stubblefield coils with accelerators like diode multipliers and joule thief/blocking oscillators and/or boost converters with wet cells (power switching with coils in tanks), no matter the size, even RF... having input schumann zero point energy (- 6 dBm @ 4 Hz or 7.83 Hz, etc...) power vacuums running off the atmosphere! even crystalizing stubblefield coils to make them last forever!

[@xeno8555]

this scalar energy or working the ether... something exciting!

[@weerobot]

Wow Where can i get that Cute 3M Breadboard...?

[@w2aew]

It is available from distributors like Digikey and Mouser: www.mouser.com/ProductDetail/3M-Electronic-Specialty/922306?qs=sGAEpiMZZMtgbBHFKsFQgrxERSzWvQuW9yILCyAbr28%3D Not cheap, but lasts a long time. I've had mine for 20+ years.

[@blobscott]

@w2aew Your videos are so informative and helpful. Thank you! I'm not sure if you take requests, but it would be great to have a clear explanation on how a transistor based astable multivibrator works. There are many explanations online, but I've found them all a bit "fuzzy." For example, I'm not sure if the capacitors must be polarized; and why when one transistor conducts, the leg of the capacitor connected to the other transistor's base goes negative.

[@w2aew]

The capacitors don't have to be polarized. It's just that these circuits are often built using large enough capacitance values that they are generally electrolytic caps because that's all that is available for that value.

[@blobscott]

@@w2aew Makes sense. Thanks! I've been thinking about the circuit more and its operation is getting clearer to me.

[@FirstNameLastName-rq1nn]

WHAT IS THE GRAPH PAPER DIGITAL UNIT YOU ARE USING?

[@w2aew]

www.remarkable.com

[@waynegram8907]

How can you tell on the curve signature if the diode is a "SUPER-rectifier diode" ? I'm not sure what makes a diode into a Super Rectifier Diode. Also some power supply rectifier diodes they will put a parallel capacitor across each rectifier diode to suppress the diodes turning on/off noise, can you show this on the oscilloscope what these parallel capacitors do to the rectifier diodes because I don't tell at all what they are doing to the power supply AC ripple voltage or DC voltage. Maybe you can show it in a video lesson how to tell the difference.

[@w2aew]

According to this website: www.diodes.com/products/discrete/diodes-and-rectifiers/rectifiers/performance-sbr/ - the main difference that you'd see is lower reverse leakage current than a traditional schottky diode.

[@waynegram8907]

@@w2aew What is in the Diodes Junction that creates a lower reverse leakage? They must put some type of material in the diode junction to make it have lower reverse leakage I'm guessing

[@thedillestpickle]

I have done quite a few circuitry projects and somehow I have never come across a need for a diode(other than LEDs). I understand their function but they just never seem to be the thing I need?

[@w2aew]

Most common applications are in AC-DC power supplies, flyback/protection around relay coils, solenoids and DC motors, analog peak detection, DC power steering, RF circuit switching and mixing, DC voltage drop and bias stabilization circuits, signal clamping, etc. If your designs didn't involve any of these (or the many thousands of other uses), then that's ok - not everyone needs diodes...

[@thedillestpickle]

@@w2aew Great response thank you!

[@taspts]

What are you using for the notes?

[@w2aew]

E-Ink tablet from www.remarkable.com

[@johnhopkins6260]

Tie B to C on NPN, to use as Diode?

[@w2aew]

Sure, makes a pretty good low-leakage diode, but the reverse breakdown voltage is quite low (typically 6-7V only).

[@johnhopkins6260]

@@w2aew 2N3055 vs. Tesla KD3055 experiment ;-)

[@WI9LL]

Is that some kind of e-ink tablet that you can write on? I want one.

[@w2aew]

www.remarkable.com I also use it for CW copy when operating portable.

[@waynegram8907]

Sometimes I see a diode package has two diodes which has 2 cathodes and 1 anode, example R711A double diode. I'm not sure what is the advantage or benefit of using a double diode package, why do you think a EE designer would use something like this instead of using 2 separate diodes instead?

[@w2aew]

There can be a number of reason to use such a device. These include but are not limited to: - Saving space when two diodes are needed in this configuration - Saving cost when two diodes are needed in this configuration - Provides thermal matching of the two diodes for applications where that may be important etc.

[@waynegram8907]

@@w2aew thermal matching would be a benefit so the half wave or full wave rectification is symmetrical identical instead of being slightly off from by the diode junction and doping tolerances?

[@waynegram8907]

@@w2aew I can understand doing that if to use that type of component a double diode that has two cathodes and one anode if you're trying to rectify a signal that you want both the upper portion the positive cycle and the negative cycle to be symmetrical and identical but I don't see that with rectification for a power supply it wouldn't really need to be exactly proportional in the same so it doesn't make sense why some designer would want to put that in the power supply maybe for a phase inverter I could probably maybe understand if you wanted to do phase inverting like in an amplifier you want the upper portion and then negative portion to be symmetrical but this isn't using the phase inverter stage for a push pull amplifier supply

[@w2aew]

@@waynegram8907 Other applications such as RF mixer applications require good matching of diode characteristics.

[@waynegram8907]

@@w2aew you want the dios to match in an RF mixers because you want the envelope to be symmetrical is that correct you don't want any tolerances and amplitude differences on the envelope of the the positive cycle on the the negative cycle of the envelope so that's why they have the package of the RF mixer they're all in one package and the thermal and the tolerances are all specced out very close tolerances because of that is they keep the envelope symmetrical I would think right?

[@praxeological]

What kind of e-ink tablet is that?

[@w2aew]

www.remarkable.com

[@waynegram8907]

What is the benefit of using half wave rectification to be the equivalent voltage as full wave rectification? what I mean is what is the difference between +12vdc half wave rectification compared to +12vdc full wave rectification? The end result is +12vdc so what does it matter if its half wave or full wave rectification if the end result is the same equivalent voltage +12vdc

[@w2aew]

The main benefit for full wave rectification is that the voltage peaks occur twice as often, which makes the ripple frequency twice as much as with halfwave rectification. This means that the output filter capacitors can be half the size for the same effect.

[@waynegram8907]

@@w2aew Fullwave rectification ripple frequency is 120Hz and the filter caps value are half the capacitance value compared to Halfwave Rectification ripple frequency is 60hz. Halfwave Rectification can source more current and voltage? or maybe some digital circuits are more sensitive to ripple frequencys at 120hz?

[@neodimium]

What about backward diode? And their uses?

[@1959Berre]

That would probably be a zener diode used as a voltage reference. They come in many different values. I Alan may have made a video on those applications, I guess.

[@neodimium]

1959Berre Actually it is not Zener diode. At least doesn't use Zener effect.

[@timothytapio4252]

What app/tablet is that?

[@w2aew]

www.remarkable.com