I work with old game consoles a lot and these inductors are found on them. Usually they are found in the NTSC/PAL encoding section, as part of the chroma trap or delay line. They are also used in some places as part of a pi filter to provide a cleaner reference voltage for analog sections--at very low current, of course.

@jayytee8062

8 ай бұрын

Yes, same with old pinball machine boards.

They don't list saturation current because they are not supposed to be used that way. They are low current devices, more for filtering applications. Size does matter when it comes to inductors for buck / boost applications. Good overview of them though.

@greatscottlab

8 ай бұрын

Well, all product description claim that they can be used for everything. So saturation current is important and should get listed.

@univera1111

8 ай бұрын

​@@greatscottlabyour really great. I never knew until now. Thanks alot.

@hanswurst3056

8 ай бұрын

@@greatscottlab But they also say that they can handle a max. power of 1W, right? This implies that they are not supposed to be used for high power/power supply applications.

@univera1111

8 ай бұрын

​@@greatscottlabcan u put the color inductor in parallel and test the saturation current of maybe 10 in parallel.

@hipihei

8 ай бұрын

These work fine in hf preselectors.. antenna filters.. or as tank coil in oscillators, etc. ..their apparent Q-values always surprices me positively..😅 more like radio stuff, not for power circuits though.. that's completely different world with air gaps and iron powder and sendust/kool-mu etc. cores..

with mixed "bag's" of components I always end up with 75% of them not getting use, because they are unusual values. Great video 2x👍

@greatscottlab

8 ай бұрын

Thanks :-)

@tyttuut

8 ай бұрын

Reminder to everyone: don't interact with spam comments, just report them.

@soundspark

8 ай бұрын

@@tyttuut Was there one in the replies? Looks like KZread actually moderated the thread instead of their usual looking the other name? Perhaps Verified users get extra help?

@Sonny_McMacsson

8 ай бұрын

Do you only do digital circuits?

@JackieBright

8 ай бұрын

​@@soundsparkmore likely greatscott deleted it himself

A useful application of these inductors is as RF chokes for small signals, or to isolate stable supplies better than ferrite beads can (for analog power rails from digital rails). One should mind the self-resonance frequency in these applications.

@jamesmetcalf3123

8 ай бұрын

I agree I work on some circuit that used these

@arampak

8 ай бұрын

@@jamesmetcalf3123 The only issue is that their ferrite material properties are not specified, so you should check with every batch to find out how they behave at different frequencies. The inductance may decrease dramatically after the frequency gets to few MHz.

@blasiushun

8 ай бұрын

TDK / EPCOS still produces them in Hungary and those components are good for filtering and LED driver circuits where space is limited. Get a good one which comes with a datasheet :)

One thing to note is the inductors don't resist current, so long as the core isn't oversaturated. They resist the *change* of current. They want to maintain whatever amount of current that is flowing through them, including no current.

These are mostly used for audio / rf filters or micro buck/boost psu in some designs that require a stable voltage in a single battery voltage powered device (I've seen even smaller smd versions in cell phones)

@greatscottlab

8 ай бұрын

Thanks for the feedback :-)

@Mr.Engine993

8 ай бұрын

Could I connect them to a 15W audio amplifier to make a low pass filter or should I put the filter before the amplifier?

@MrBradleykeith

8 ай бұрын

@@Mr.Engine993 before the power amp would be preferable I would think.

There is such a lot of hard, time consuming work put in to produce your videos - very informative and well presented

While I was at uni, the latest craze in power engineering was pcb inductors. You’d have a multi layer board and use the inner layers as inductors / caps / transformers. Maybe that would be a good video.

@creeper6530

4 ай бұрын

I can imagine caps, maybe even inductors, but transformers? Doesn't a PCB have no metallic core, making it super inefficient?

@matthewmaxwell-burton4549

4 ай бұрын

@@creeper6530We are talking about ultra-small stuff here. Like micro-scale wires, at that size, it's not too difficult to guide the magnetic flux using other wires etc...

Great movie! These elements work perfectly for all kinds of filters in audio and radio circuits. You don't need to transfer high power, just filter out high frequencies. :)

You answered several doubts I had for such inductors, and demonstrated them in the scope. 👏👏Thanks 👍!

I have used them, and they are often used in solar lights in combination with the yx series solar chips

Always excited when new uploads appear! Great video.

I saw Particle had made some changes this year, including making a free tier for people experimenting. I'd like to see their cellular device used to make an ebike tracking device. Being able to keep track of my ebike without a monthly fee would be really nice.

@greatscottlab

8 ай бұрын

I can put it on my to do list :-)

@nimoy007

8 ай бұрын

I'd be very interested in such a project as I too own an ebike.

@gf2e

8 ай бұрын

They’ve had a free cellular tier in the USA for awhile. I have one of their boards in my RV to monitor my fridge. I have 200W of solar but my part of the US doesn’t get that much sun, so I need to keep track of the battery SoC to ensure my fridge doesn’t defrost. Nifty platform. I tend to roll my own stuff so I didn’t test all the features but I like it. I’ve upgraded my RV with unlimited 4G, though, so I will probably be switching away from Particle. I also want lots and lots of sensors in lots of places so it’s impractical to have Particle devices everywhere.

@wrathofsocrus

8 ай бұрын

@@gf2e You're right, it was probably longer ago that I saw the changes. I have a bit of brain damage and get time scales confused. I don't recall seeing any recent news from them in the places I normally look. I always thought they had interesting stuff but never used it myself. I appreciate hearing about your experience!

@liamfitzgerald7298

8 ай бұрын

Lorawan maybe

I had been curious about those. Thanks for the breakdown.

Great video 🙌 I learned a lot in such a short amount of time honestly. Thanks for driving in on this often inconspicuous component :)

Welcome back Sir Scott! Thank u for sharing

I'm glad you made this video. I, too, had a small box of these laying around for a number of years, but I never used them because, as you pointed out, it is impossible to find reliable data sheets on them.

I found one in my tool cab that "was gifted by the lab" to me as a souvenir. I have encountered a problem when I am designing a Bluetooth wireless headphone that the RF transmitting noise will leak through the power bus to be amplified by the power amplifiers. so I just connect the ring inductor in series to the Bluetooth board and ass a bypassing cap. It miraculously made the noise dissappear.

@greatscottlab

8 ай бұрын

Haha awesome to hear that. Good application.

Great video, like you I did the same thing and still have them in a bin collecting dust. I figured out they are very specific to filters and very small power supplies, loved your method of measuring saturation current, but I love your LCR meter even more, I have a cheap ebay one....

Excellent video. The most I will learn in any 10 minutes I will spend all week.

I don't think I've seen a video on these before... i enjoyed this one very much. Thank you...👍🇮🇪🙏

That was amazing loved the interesting angle you can at inductor properties and info. I would watchin this kind of video about many basic parts

I use them for tweaking the LED current on rechargeable solar lamps. They can also be paired with a ceramic capacitor and LED to make "wireless" LEDs.

Good content. I was waiting for an EB video for a long time. It was worth the wait.

@greatscottlab

8 ай бұрын

Awesome. Glad to hear it :-)

I certainly did learn something new . It was how to visualise on a meter the saturation current and the effect by heat !

I saw those resistor looking power inductors being used in cheap outdoor lights that are used in the joule thief circuits

@greatscottlab

8 ай бұрын

Yep. That sounds like a suitable application

Thank you for this very good explanation of the Inductors. In fact, you have detailed an important aspect of inductors that I hadn't really taken into consideration -- the saturation current. Thank you.

Interesting information and presented in a sequential manner. my regards

The cleverest use I have seen for these cheap inductors was in a video titled An Almost Solderless Crystal Radio. It's a breadboard AM radio that uses these inductors rather than winding coils to build a powerless radio! You like to shrink circuit boards; this radio could be shrunk to fit almost anywhere such as in an ink pen or even into the crystal radio style ear piece used to listen to it!😊😮

Nice explanation of inductors. I had problems with creating DC/DC converter at my own but now I know why :D

I have been using those inductors in many digital circuits, usually for power supply filtering but other uses as well, for many years. If you are building circuits, they are great for keeping the current draws affecting other circuits on the board, when used with filter caps as well.

Like most people pointed out, color ring inductors or the equivalent in SMD footprint are not used for power applications but for filtering. I should also point out that datasheets for this kind of devices do exists which usually state: inductance, tolerance, minimum Q, minimum self-resonant frequency (SRF) in MHz, DC resistance (DCR) in ohms, and rated current. These values are also specified and tested at a specific frequency, like 0.8, 2.5, 8, or 25 MHz. In my opinion, they are certainly not particularly useful in the through-hole footprint, so SMD are more prevalent.

Very interesting to understand the difference between these kinds of inductors. Thank.

Excellent content as always .. Thank You .. Cheers :)

Great EB video as always. Yes i also did use them when i replaced the original inductor inside my microwave, as i wasn't able to get the original inductor, i used that colour ring inductor. Working perfectly till date. Thanks for a ton of info! Appreciated!!

@greatscottlab

8 ай бұрын

Thanks for the feedback. Good to hear a practical application :-)

@ATSystems

8 ай бұрын

@@greatscottlab Yeah. It was in series of the mains input trace on the pcb. It was mostly for filtering and inrush current limiting purpose maybe.

Great video. Some of chokes, based on powder cores, have no specific saturation point.Inductance slowly decreases when current rises. Try to find some of them and test using your circuit.

Very well researched and explained

Did you mention to teach one time. I never understood the saturation until now, thank you

Thank you for another great video Scott! This is my hobby and I would not be where I am now without your help!

@greatscottlab

8 ай бұрын

Awesome to hear that and glad that I could help :-)

It’s cool seeing practically what happens when the core saturates!

I use color band inductors in joule thief circuits. Much easier than winding a ferrite core. I suspect in another couple generations all through hole components and maybe discrete components altogether will be a thing of the past. Nano controllers and software.

fun project with these, make a one or two transistor regenerative radio receiver (you can couple two axially to make a "tapped" inductor) .

Great video Scott! Would love to see a diy or buy for an LCR meter. Something Arduino based for the diy option may be an interesting project.

I've seen so many of these colour ring inductors used in my AM/FM radio receiver.

We used particle photon in our intro to computer science class in college. That was ~4 years ago. I really enjoyed using that MCU. Programming it is nearly identical to programming Arduino, and you can open their IDE on any webpage anywhere, then flash code to your MCU through wifi. I havent used one in a few years, but I should start using them again

In the past life I had, I measured saturation current using an LCR meter and running DC current through them. I isolated the DC power supply using two much larger inductors which caused minimal error on the inductor under test's value. Its clumsy, but it works.

@user-ru5xq3er6s

7 ай бұрын

Can you give a diagram of how to measure the inductor saturation current? Thanks!

@kenmore01

7 ай бұрын

@@user-ru5xq3er6s Hi! A diagram is hard because I'm between computers and jobs right now, but the premise is make two very large inductors which can handle a lot of DC current. The inductance should each be around ten times what your inductor you want to test is, and physically large too. I recommend a fairly high permeability powdered iron core (don't use ferrite, they saturate too easily when DC current is passed through them.) Put one on each side of your inductor under test. Measure the inductance of what you're measuring, then connect a current limited power supply across the inductors. Increase the current slowly, and watch the inductance drop when you approach the saturation current. You are really looking for any non-linearities, because that indicates that you're getting there. Those tiny ferrite inductors won't do well with DC current because they aren't designed for that, but you can find out where the limits are. The meter or LCR bridge will tell you accurately when you're reaching saturation.

Also they can be used to cheap out. Just imagine you are building 1 Million devices and you can save 0.47€. It's nearly half a million. Added bonus is, when you do it right, the device breaks down after the warranty. Its proven that some devices would had a few additional years, when added 1€ worth of better components. The added costs per device is tiny. Even when you add research to check on how "bad" a component needs to be, so it just passes the warranty, its still worth it for them.

@greatscottlab

8 ай бұрын

True and a bit evil ;-)

When im ready from plumbing school i will contiune to electrician thanks to you!

They are useful for LC passive filters for various RF signals. There is software that will choose the best 5% or 10% values to give the desired response. They can be used in lowpass, highpass, bandpass and other filter circuits. They can not handle large signals as they saturate.

I bet they can be helpful for tasks like filtering the ICs DC pins in conjunction with the blocking capacitors. Usually they don´t pull that much current. I need to try that on my own !

@greatscottlab

8 ай бұрын

Sure. Sounds like a suitable application.

Wow. 40 years ago I learned this lineal current rising in the yoke at TV course Wich makes the horizontal sweep. Best wishes!

It might be a nice idea for a video to gather together this and other small under documented items and make a guide. Test the small inductors you have and maybe purchase a small sample and see if they are "standardized".

yes best video in a long time Mr. Great.

@greatscottlab

8 ай бұрын

Glad you enjoyed it

my grand pa used to play with small kits and those are the most common parts back in 1990~~~ wish i could stick a bit more on electronics.. 15 last years i drop em off!!! thanks for the videos!!!!!

Dear GreatScott. Im using these inductors in receiver and transmitter circuits and they perform quite well. For low power applications these ar quite good components.

Great Scott,, Awesome video…

Thanks a lot for the video. I was building a Geiger counter and wanted an inductor for the boost circuit and struggled to find one locally with the value I wanted but these color codded ones were available. I didn't know if they're going to work or not or what the difference between them and the regular and the SMD. I just tried them and they worked (primarily because the Geiger tubes doesn't draw much current) but not until I watched this video that I knew the actual difference.

Such small inductors can also be ideal as RF-chokes (to decouple circuits but also for example in microphone leads to prevent radio reception) and in tuned circuits where the current is usually very low.

Excellent video. Your "bench setup" for measuring saturation current was excellent. I strongly recommend a second video where you walk through the reasoning for each of the parameters you selected in the function generator and the scope. (e.g. why repeat at 100Hz? Why did you select a pulse time below 5uS?). The way you showed visually what what saturation looks like was awesome, and briefly touched on the thermal runaway. Excellent. One small Q/Thought -- the stored energy in the inductor -- it's dissipated through that flyback diode when the mosfet is off, right?

@sinderw

8 ай бұрын

pulse should be frequent enough otherwise the oscilloscope will get lost. pulse width was probably chosen randomly and slowly increased till saturation was observed

This 3 cent inductor was exactly which needed to be replaced in our fancy kettle, which we were ready to dispose off since it stopped working.

Like you, I too have them things in a bin for the last 10 years or so and have never really used them... very much looking forward to this. Thank you

@greatscottlab

8 ай бұрын

Haha such things happen. Glad I could finally get to my 10 year old components :-)

Great job! Please make more some fundamental videos like this!

@greatscottlab

8 ай бұрын

More to come! It just takes a bit of time until I get to them :-)

7:51 air core inductors have no saturation current. I would love to see how one behaves on your saturation tester.

Great, Scott! 👍

I have a slot in my bins cabinet with the (I believe) exact collection of these little color ring coils. I have used them in many RF and other low power places, but never what you have done here. Cool as it was to see these little gems fail as they did in your experiment, I was told they are not meant for power systems, but more as an RFI and other lowe power systems. Thank You for the knowledge! Peace

Thats funny. I was in the exact same situation. When I started getting into electronics I also bought a kit with these inductors, never used them and didnt know their application. Until I first used them in a filter design last week. What a coincidence

I like them for simple RF projects like shortwave radio reciver - not for the main resonant circuit, there are better types for that but decoupling and even for a simple oscillator circuit these will do well...

At 10:25 I'm pretty sure that the "rated current" in the datasheet represents the saturation current. It seems unlikely that the one in the third row is limited to 500mA by heat dissipation, as its DC resistance is only 0.26Ω, i.e. dissipation at rated current is just 65mW.

Great video. tnx

They are not intended to be used as power instructors. They are usually called RF inductors used in filtering. If you buy them from a proper distributor (Mouser, Digikey, Farnell, etc...) you also get a proper datasheet. Great video anyway!

Really interesting indeed! Thanks a bunch, dude! 😃 Stay safe there with your family! 🖖😊

@greatscottlab

8 ай бұрын

Thanks, you too!

Use them with a capacitor in front of ADC inputs to filter noise.

There are also capacitors in that "resistor" form factor. I see them a lot in retro computers.

What about using these inductors in series to improve the low power barrier!?

@GabrieleR95

8 ай бұрын

@@DJMANDY467 just like it's usually done with resistors, they "share" the voltage drop across them, so the power dissipated by each one of them drops. (Edit: the current is the same though, so the saturation can still be an issue, but the resistive power would be shared)

@Kalvinjj

8 ай бұрын

if I'm not wrong, you would increase the inductance, but not the saturation current. Does solve one part of the equation tho.

@hugoslav843

8 ай бұрын

​@@Kalvinjj2 in series, 2 in paralel, increases saturation current, the inductance remains

@harrison00xXx

8 ай бұрын

@@hugoslav843 yep Quadruple the component count tho To the point you are better off with a smd component or even a big coil which datasheet mentions the saturation current you need

@hugoslav843

8 ай бұрын

@@harrison00xXx Well, for a hobbyist, its usefull to get by with what you got and these are handy

I've only ever used axial lead inductors to make joule thieves, they're pretty interesting in that regard.

Great informative video! But I think you forgot to mention one important aspect. Radiation! And so, unless you are building a transmitter, these coils are only suitable for low power, low frequency applications considering EMC.

Great as always 👍👍👍

@greatscottlab

8 ай бұрын

Thank you! Cheers!

Nice. I got some of those inductors in an assorted electronics kit I got long ago. Took me a while to figure out that they weren't resistors.

@greatscottlab

8 ай бұрын

Haha yes. Now you know how to use them.....hopefully ;-)

great Scott why do you think the other coil with the same inductance preformed twice as good?? Would coil diameter help dispatch heating at higher temperatures??

There you go, I learned something today.

@in SMPS applications, it's useful to know the ACR, DCR, and I(sat) Clearly, the I(sat) is almost directly related to the *amount* of core material, DCR to wire size, and ACR to core losses...in an LED driver that we were developing with TI, the simulations showed about 87% efficiency, but the prototype boards were always a couple of percent low...this is at 1 MHz or higher... replacing the smd inductor with an air core inductor brought the performance to equal simulations... BTW, for anyone who cares, I came up with a simple way to figure out ACR and parasitic capacitance, using an oscilloscope probe and FET switch, measuring the ringing frequency with e ~11 pF probe capacitance, adding a known capacitance, to change the frequency of the ringing, which also allows you to get a differential measurement of the real probe capacitance...then, by changing the capacitance and ringing frequency, and measuring the decay of the ringing, you can calculate the ACR at the ringing frequency...

You're not the only one. I have the same exact kit you bought and have been ignoring them for 10 years lol. Every once in a while I'd pull one out just to see what it would do to like an LED or something small.

They are used in very low power, low cost, solar powered garden lights. Those you buy for a dollar and stick in the ground around your garden. Here they are part of the switched mode supply to charge the NiCd cell during the day.

Thanks for that informative video

Twice in this video, you say that inductors “hinder current flow”. But don’t you mean that they “hinder CHANGES in current flow”?

I've had some cool projects with Particle Photon 1st gen. Great microcontroller, only drawback is that you can't find them in EU. At least 2-3 years ago.

@particle_iot

8 ай бұрын

You should definitely be able to find the Photon 2s in the EU nowadays!

Could you tell us which LCR meter you using and do you suggest your LCR meter? manually calculating with an oscilloscope or your LCR meter, which one would you choose?

Super and very informative video bro👍👍👍👍👍

@greatscottlab

8 ай бұрын

Thank you so much 👍

Thank you for digging through the ENTIRE internet! :)

There was a time when inductors like these were about the only inductors available off-the-shelf from component distributors - well except for big iron-core jobs. One of the things that data sheets will reveal about these sorts of inductors is that the construction is often not the same for all values in a series. Low values are often "air" core. Instead of being wound on a core with permeability greater than one they are wound on something like ceramic, the same as used for film resistors. The core doesn't contribute to the magnetic properties, it is just a physical support for the winding. As the values increase, other core materials are used. Intermediate values may use a "powder" core with moderate permeability. High values may use a ferrite core. Saturation properties vary a lot with core material. Ferrite saturates the most easily. Air doesn't saturate at all. Externally all of the inductors in a series may look identical except for the markings, though the properties can be quite different beyond just the difference in inductance. Going up or down in value by one "step" (e.g. from 22 µH to 33 µH) might come with a significant change in properties. Very similar inductors can be had in surface mount packages. In surface mount you can also get inductors in the nanohenry range, intended for RF circuits, often for impedance matching.

Many years ago I bought such an assortment, and I happened to come across it yesterday when going through my parts bin. Wondering if they were any good and how to measure the saturation current. Thanks for the video.

@greatscottlab

8 ай бұрын

What a coincidence. Glad I could help :-)

I can highly recommend to buy, and read, the book "Trilogy of magnetics" from Würth Electronics" but I guess there is a good chance that book is already in your personal library 😉 There is a lot of basic knowledge that I kind of forgot after school or that we never learned.. It contains a lot of info on how to use which type of inductor for which application

So heatsinks could be added to the inductors.. Would using them in parallel work to increase the Amps?

I love these things. If you're using them anywhere near their saturation point, then you are missing the point. They are meant for small signal processing. I use them quite a bit in the front end processing of VHF and below.

Yeah, these you have to get from a reputable manufacturer like Vishay or something to get the full specifications. There's power inductors and then there's inductors for low power uses like in RF work which often it's best to use self wound inductors unless your form factor is tight then these and other SMD inductors are a better choice which then require you to build your circuit (like filters) around common values and combos of values.

it also absolutely in audio . now we use rc opam circuit for filter in parametric analog circuit also audio now shift to digital

Not everything needs high current, these are great for stabilize for audio/video IC's

Had my hopes up, that you might address the "slick and side movement" of the rubber cover. Maybe I should search for premium quality clips. Thanks for all of the video's.

Solar lights use these color ring inductors a lot to boost 1,2V to ~3V, by changing the inductance one can control the current that the LED is driven with._

The (I assume) power supply of my milk frother (230V -> 12V) uses one. Stopped working one day and after opening it it was kinda melted. I ordered new ones and they just arrived. Will see if the new one works, because when I just short the broken one, the device works fine so I assume it's only used for filtering.