As a kid in the 70s, I got a hold of some red LEDs, which I thought would make nifty tail-lights for my slot-cars. I drilled out holes for them, and I did some very simple calculations with Ohm's Law, and soldered in a resistor to each LED, and wired them it to the power source in the cars. I can't believe how perfectly they worked, and lasted many years for the life of the cars.

A dark emitting diode sounds cooler than it should.

Bloody hell Clive, watching your hands around those live contacts, I'm a know you know what you are doing, but it still made my bottom pucker.

Possibly the best description of a bridge rectifier i've heard.

You're the only one who stands a chance of teaching me basic electronics in a way that sticks. Please make that video!

This is likely the single most useful video to ever grace KZfaq with it's presence.

In my opinion that was one of your best videos clive! Very informative and entertaining. You're like the bob ross of electronics with your calm voice.

For some reason I like the capacitor dropper concept, AC allows a lot of things to work that would never work with DC, then you get into radio frequency and it all chances again, I have worked with 2-way radios for 30 years and I still learn things everyday, as always love to watch your videos.

My self converted tungsten to LED Christmas lights are still working Clive. Thanks for that video almost a year ago

I like the burns and stains on your workbench. There's a lot of KZfaq history there. :-D

I must have come back to this video at least 30 times in the last six months, it never gets old

I was hoping for a SED: Smoke emitting diode.

Love how big Clive is always admitting to his errors. And I love the little Math tutorials he embeds in the show. That is very very helpful

I always get a bit nervous seeing your hand 1cm away from a live wire :D

watching this with auto generated subtitles is so great because every time clive says "neon" it comes up with a different word

My test block arrived today and gave it a jolly good going over and I love it, should have bought one many years ago, to those thinking they are great but too expensive, do yourself a favour and just buy it you won't regret it after the first time you use it and it will outlast yourself.

Love the "dark emitting diode" line. :) It's easy to see how much you love electronics watching videos like this, and also how much knowledge you have. I know it's a few years ago, but I still haven't managed to watch all your videos yet. I really enjoy the way you explain things in such a matter-of-fact way that is interesting to technically minded people, but also simple enough for non-technical people to understand.

Looking forward to the electronics video - I remember most of your 'basics' one from a while back

Thanks for showing us this Clive. My hat is doffed. You are a gift to the likes of me, who has always wanted to understand electronics, but never had the time or ability to pick this up from books. Your method of showing us works brilliantly. Thank you so much.

I have been working in the electrical/electronics for over 63 years and your videos are the best in all detailes m

I'd enjoy seeing him solder together one of those matrix of LED cubes. I could watch that soldering technique for quite a while.

Dear RI Christmas Lectures, please can you get Big Clive, it would be the best lecture ever!

Thank you for going through all of these different possibilities Big Clive.👍

You putting an LED straight across the mains reminded me when i was around 11 y old,i put a 6v bulb across the mains,boy did that go bang,the glass exploded literally.But 49 years on and ive had a great career being an electronics engineer.Good vide Clive.

Your videos are super comfy.

Super knowledge-rich episode! Thanks, Clive! Dark-Emitting Diodes, for areas that are a bit too bright.

"Dark emitting diode" :'D It's small details like this that make this channel the best there is. Not fancy interviews, CADs and overly complex projects.

Clive to the rescue. I was trying to understand how the 24VAC digital inputs work on an old Carel pCO controller and with my rudimentary electronics knowledge I couldn't wrap my head around it. This video cleared it up for me. Basically the heart of it is an optocoupler, so practically an LED (on one side of the device anyhow). The rest on the input side of the coupler is what's in this video (they use the "one diode method" instead of a bridge rectifier, but the resistors and capacitors are there). Great content as always. 👍 *a fellow fridgie *

I keep hearing Clive say "neen" instead of "neon." LOL

Merry Christmas! Looking forward to that electron theory, always makes me confused when you realise electrons flow the opposite way to current.

+1 for "quite violent" and "visual dots in your eyes for quite a while". Big Clive you make even the most dry material quite entertaining.

I’ve been watching you for some time now, and you do this better than anyone else. Your wry sense of humor makes a big difference. I can laugh on my way to understanding.

I like this - The Big Clive Christmas Lecture.

Dude you should be in some kind of soldering tournament your skills are amazing!

One of my favorite Big Clive Videos. I find this relaxing... and cheaper than therapy.

Five years after posting, this video turns up on my recommended just when I'm looking at a solution to this sort of problem! Bravo algo!

My favorite approach is to use "capacitor dropper" method (as in your video) but with two LEDs in parallel and opposite directions. This allows current to flow in both directions and you can get rid of the bridge rectifier. The only drawback is that now you have to deal with more photons than you originally need but then again these are not photon torpedoes; it is OK. :)

It's really annoying when the really bright blue LEDs are used as indicators. i usually end up covering them with black insulation tape

These informational videos are very much appreciated. I dropped out of general electronics in favor of modular computer work years ago, so a refresher was definitely in order.

I like the idea of a dark emitting diode. Switch on the power and it sucks up all the light. :) Very informative, as always. LED's must have changed over the years, I recall back in the late 70's accidentally plugging in an LED instead of a neon on a piece of equipment and getting quite a nasty burn when the thing exploded.

Clive! You failed to put the neon directly across the line. That's often MUCH more exciting as the wire leads vaporize. Follow up video!! Perhaps for New Year's, we can find a 1uF/50v electrolytic in that same spot?

Just what I was wanting for XMAS. Need to replace an ancient AC 8v 30mA Radio lamp (backlighting the frequency board) with an orange LED or something else...just want to keep it looking aesthetically correct but technically updated. Thank you

Excellent video. I'm putting together a power supply as a winter project, using Chinese boost and buck converters plus a DPS 5015 adjustable control unit. Got the internals somewhat figured out so it was time for all the lights and switches on the outside. I figure if you build something like this may as well have lots of lights. Lights have been my thing since I was born. This video helped a lot and just about perfect timing. Thank you very much.

Really enjoyed that Clive. I'm a fan of the longer format video you do. The electron theory video sounds like one to look forward to. Love ya work.

That was a very practical video. Thank you! So which is your preferred method for implementing a high side LED indicator, Clive? I'm guessing the capacitive dropper w/full wave rectifier.

The stability of neons depend to a large extent on how parallel the electrodes are inside the bulb. The more un parallel the electrodes, the more unstable is the discharge. Kinda ironic that the less care in manufacturing, the more unstable they are but the more flicker (candle like) they are. So Chinese ones are probably best!

Thank you BigClive one of the best (for me) videos I have seen about LEDs and resistors. Looking forward for your longer video. Maybe I can retain more.

Excellent. For conserving power on a water heater for showers, I used 2 LED nightlights as indicator lamps. Purchased from Dollar Tree, I took them apart and wired 1 to the mains on the water heater indicating when it is turned on, and the other is wired to the heating element indicating when it is heating. When the 1 LED on the heating element goes out, the water is sufficiently hot for a shower. After a shower, I turn the water heater off from the mains breaker, and a quick glance at the water heater shows it is off. No sense in the thing keeping water constantly hot if I do not use it. They pull a lot of power as you know. The LED's have an inline resistor and the diode across the LED as you show here.

What if you use one of those bicolor LEDs to eliminate flicker? Only issue is the color changes every half wave but it would likely blend together in a way that looks nicer than the standard on-off cycle.

Oh have a smashing christmas clive :-D

This single video has taught and inspired me to start experimenting and learning electronics even though I had no prior knowledge of electronics; I remember a few fundamental laws of electricity from high school 15 years back.

Thanks for this video. I wish I had you as a teacher for my electronics classes. Perhaps I'd remember a bit more than I do, as your explanations are much clearer, than the dry descriptive theory we used to get. 🤷🏼‍♂️

Thank you Clive for the video. I found it humorous that you should mention about the Neo. getting less bright but lasting longer. That indicates to me, that there is hope for me as I find myself getting less bright as I age, now 65, so maybe I'm destined to live to a very old age? Any thoughts? All the best to you and yours, Billy

How do you tell the difference between the similarly coloured LEDs of differing technology just by looking at them (not powered)? Is it just from using them for such a long time?

Great help thank you . I replaced a burnt out Neon in a mains adapter strip with the capacitive dropper and bridge. I used a 330k resistor which gave me 0.7ma for a blue LED and it was plenty bright enough as an indicator. Using the 1k one would have lit the room up at night lol. Thanks again.

Im so glad I found your channel. You explained the full bridge rectifier perfectly. Thank you! I can now say i understand the concept thanks to you. Wow, really, I learned so much from this video.

Well now I know where dark energy is coming from. The universe is filled with all the old blown LEDs thrown away from parallel dimensions.

a rectifier and capacitor over the led is the best

Very good instructional video. Liked how you showed several variations of the LED across the mains. The capacitor example was quite interesting. Thanks!!

Happy Christmas from Down Under! Thank you for another year of excellent (and in-missable) electronic entertainment (and education!) We are all looking forward to your "programme" for 2017!

haha now its a DED - dark emitting diode

Hi bigC, What would happen if you used the neon tube in series with the 120k ohm resistance, would the light emitting diode illuminant and the neon tube? would it stop the light dancing in the neon tube as it won't be alternating electricity since the light emitting diode will stop the electricity it does not pass like the + or the -. I could be very good at this stuff bigC, obviously, I wouldn't be able to actually do it, however, I would be able to talk like I could (talking is my strength my dad said.) that will so annoy the boys in my class. Anyway, I won’t be talking with you until after Christmas now, as I am finishing off making myself a dress for a party that my dad said I may go too. I didn’t think he would fall for the bit about the party being in the oap’s home. I will be in so much trouble when he finds out. Happy Christmas Big C. Sarah.

Man oh man, I have to say.. You make soldering using only your 2 hands look so easy! It's just not fair at all !! I've recently been trying my hand at it, and it's not at all that simple holding everything still enough. Glad I found this particular vid as I've very recently been thinking how I'd like to put LEDs on a few (or maybe all) of my projects. I deal with a 110v supply, so it's especially fortunate that you've covered that. Thanks for All your vids tho, & keep taking them to bits, won't you! Cheers. J.S.

Hi Clive, I absolutely love your videos. You have taught me so much, I hope you can get some time to do the video on electron theory as you mentioned here. You can explain stuff so well and i would love to hear you explain it all in a language that we all can so enjoy and learn from.

really looking forward to the beer-fueled electricity basics video. It's frustrating that I understand some bits of circuitry, largely due to this channel, but I don't really get any of the fundamentals.

how do you know what type the led is ' gallium etc

Very nice demonstration of using LEDs on an AC application. Made up the 220K resistor and the 5 green LEDs (bridge rectifier and LED load). Works quite well with 115VAC 60hz and works perfectly on 115VAC 400hz Quite bright and steady. Much better than using the NEON bulb and 220K resistor that is a dull orange glow. Thank you so much for the information :)

Excellent video Clive, not only interesting to most, but lots of good teaching points too. You really should expand this idea to teach basic electronics in an 'as you go' with gratis visual tips for safety and soldering technique. Very well done..

Where did you get the Chinese LED tester?

we should add a wiki article about the founder of the DED. Or should we say DEaD? :-D

You ever have one of those BELLS IN THE HEAD moments? Just had one where the bridge rectifier finally rang the bell and made complete sense. I always had problems seeing exactly how they worked even though I have made a few of them and they work great. Suddenly as you were explaining it, it all made sense. You make a great teacher, thanks much.

A really informative, practical video Clive! Loved it. Helps us plebs understand more when it comes to some of the more complex videos.

Dark emitting diode... When you notice that the abbreviation for that is literally DED

You can also do it with two resistors in series. Connect the LED across the smaller value resistor designed so that the voltage across this resistor never exceeds the reverse voltage limit of the LED.

People tend to forget basic parts have fairly low breakdown voltages. The 250V for the resistor is one of the reasons I always spec in a string of at last three in any mains indicator or sensing circuit.

I plugged a 3mm LED from a PC case into the 240V mains in my bedroom when I was little, and it was spectacular! White sparks shot across my bedroom with a loud muffled pop/puff sound. It was so loud and bright, my mum walked in and asked what happened. That's how I learned that just because an appliance plugs into mains power, doesn't mean it uses that mains power to run everything inside it

Excellent video, as someone who doesn't know anything about these components I look forward to seeing your proposed video! I'd rather watch your videos then TV any day!

Indescribably useful, Big Clive! Your videos genuinely promote understanding.

If I was in the room during this video, I would be as far away as I can, since I have always seen the mains as something that would require big components and thick cables, without it burning up or arcing. So seeing this really amazes me.

2021.... and it's getting increasingly difficult to get neon indicator lamps. The bulbs still available, but the indicator housing with lamp, more difficult and expensive. And annoyingly, on Amazon, the many many vendors of indicator lamps that actually contain LEDs insist on including the keyword "Neon" in the title or description. That trend makes this video all the more valuable.

I ordered off from China for some of the nixie / neon bulbs that you showed in the first part of the video and they came in today. I had forgotten that you had put a resistor in series with it and gave it a try by just touching the leads to the open line voltage terminal blocks that I have on a test platform that I use for Arduino sensors and such. It definitely makes a nice arc -- it looked like I was arc welding. Figured that I had blown the bulb, so I looked at it under a 20x magnifying loope and it didn't look that bad, so I figured I would give it another try. Figured that if it arced again, it didn't burn up. I'm holding this bulb in a pair of forceps -- without any insulated handle. Yeah, maybe not that smart... Well, it stuck an arc again and my hand jerked back, it flew, and I then got to spend 15 minutes crawling around on a carpeted floor trying to find that little thing. And then I spend some time searching for this video again and see that I had forgotten about the resistor... Ooops...

Clive, please make that huge video you mentioned. To be honest, I have nearly no understanding of such things, yet I watch every video you release. I long to understand!

Just love your vids. Only this evening I put a neon indicator on my off peak system to let me know when on or off. Then you have done a video and I now know I did the right thing!

We love your videos so please allow more clearance between yourself and the national grid!

Excellent demonstration. Capacitors would likely be more expensive than resistors, but I prefer them in AC circuits. An LED is designed to function between 20mA and 30mA and will present a fixed voltage drop, say 5 volts. A resistor of a given value will pass a given amount of current based on the voltage across it. (ohms law) This is fine if the voltage is stable, such as those likely to be found on a DC supply. Mains voltage can be a bit more variable. A cap of a given value, however, will pass a given amount of current based on the AC frequency without regard for the volt across it. The LED will drop its design voltage while the voltage drop across the cap will drop the rest of the voltage and fluctuate as needed. Using a bridge rectifier, as @bigclivedotcom demonstrated will still work. Even better, another cap parallel with the LED will smooth the pulsing DC and reduce the amount of flicker.

Thank you Clive for yet another excellent, fun and informative video! And a Very Merry Christmas to you! 🎅🎅🎅

Really good "back to basics" video - Have a Merry Christmas Clive.

Looking forward to that electron theory video big lad. Hope you had a good Christmas and keep up the good work!

I now understand what a bridge rectifier is (how it works). Thank you for the simple explanation!

A voltage divider (resistor ladder) is another great approach that intrinsically limits short circuit current and resistor heat dissipation.

Great video for those wanting to try this out. The part that made me lmao was the "Dark emitting diode"!! Priceless. The funny thing is if you put that up on ebay someone would buy it with sinister plans.

It is video's like this that make your channel so special!

For 117VAC, I have used R/G LEDs in series with 33K 1/2 W or 68K 1/4W resistors. The R/G LEDs have 2 LEDS, back to back, you can get them in R/R also.

Thanks for this Clive, very nice videos. I have used LED/Diode/Resistor for years in gear I build. Saves a lot of time when hunting faults. Kind regards & greetings from Africa.

thank you for your continual educational content Clive. You are a great KZfaqr and I truly appreciate your videos.

yes bigclive, do the video, as you got the skill to explain things in a way that, even a dumb finnish guy like me can understand them. Watching your vids got me interested to really learn more about the whole subject of electricity and electronics.

Instructive and useful video. Thanks for the posting. Your approach is comfortable and well paced.

Beautifully presented and explained. I look forward to the follow-up video you mentioned. Thank you.

Thank you Clive...in all honesty I understand little of what you say, (but am learning elementary stuff gradually); I do though thoroughly appreciate your postings, and thank you for them...Happy Christmas Dave

Thanks Clive 🙏 Finally I understood the sense of that X2 type capacitor.