The First Light Emitting Diodes 

In the mid 1970's I was in High School, and had subscriptions to every amateur electronics magazine you could name. The buzz about LED's had been around for a while, but they were lab curios, operating in pulsed mode at reduced temperatures. And mostly infrared. Then the commercial units appeared, and I had to have one. The glorious day came when the local Radio Shack had its first visible red LED! It cost about $8.50 in 1974 dollars! I saved my money, mowed some yards, and bought the darn thing. I hooked it up to the power source, and marveled at the ruddy glow! Here was light, being created at the atomic level! Quantum stuff in your hand! It was magical, and I still feel that sense of wonder from time to time.

Can I just say how adorable it is that you have a favourite LED

Just love LEDs too, it was genuinely exciting going to Radio Shack in the 80s and getting an assortment of random red, green, and yellow LEDs. Also amazing to see the continual progression of super bright red LEDs, it seemed impossible that they got so bright. The first blue LED I ever saw was in a diffused white package, very dim but so surreal after a life of red and green or yellow for so long!

As you are probably aware Fran, if you shine a light source on an LED, it will generate electricity much like a solar cell. Red LEDs are more sensitive to red light, Green are more sensitive to Green light, and depending on how the Blue is manufactured, they are more sensitive to blue light. This means that you can take an RGB LED and shine white light on it... and have the leads connected to the A/D input of a microprocessor. Then you read this level and presume it to be this highest level... scale it to 255... with no light being 0... and you have a color sensor. Something interesting to play with.

I love them too, Fran. In fact, I secretly call them *_Love Emitting Diodes!!_*

These are beautiful LEDs as well as interesting historical "artifacts". It's amazing to compare these to neo pixels or the LED lightbulbs that are becoming common now. I remember the first time I read about blue LEDs in Wired. It was such an amazing breakthrough!

Blue LEDs sure fascinate me. I tinkered a bunch with breadboards as a kid in the late 90s, and one day my grandfather brings home a blue LED for me. Never saw anything like it, there were no blue lights in consumer products. Seeing them in this video still brings a little nostalgia.

As a career electronic geek, and working with LED signage on the daily, seeing some of these early units is really cool. I have to attribute LED's to my introduction into electronics, playing with dads junk box. thanks for showing us your collection, greatly appreciated

I remember having an early LED display calculator. I opened it up and saw one of those circular rheostats which when adjusted actually changed the clock speed! You could slow it down so much that you could see in slow motion the scanning of the 7-element LED number displays an element at a time. You could also overclock, which reduced battery life, but gave you faster results. (Themdays a SQR request would take a cuppla seconds to calculate(!), due to both limited hardware and poorly optimised algorithms).

You're making me all nostalgic. I bought my first LED's from Radio Shack as a kid in the late 70's - "jumbo" (5mm) reds. I still have them in a large tackle box with thousands of newer ones. I also have a 70's green LED with a red die inside, although I discovered in high school electronics that, with sufficient voltage, a green LED will light up orange for a second before exploding. I had a Western Electric Trimline phone with one of those unusual green LED's behind the dial. The color was different enough that I didn't know it was an LED until I opened it up. Ill never forget my first sight of a SiC blue LED - a sky-blue color that isn't seen in newer ones. Regarding unusual shapes of 70's LED's, my favorite were the ones with a faceted top. Great memories!

_"Happyness is a 10 pound bag of 7segment LEDs"_ (Fran Banche)

seeing frans smile as she geeks out hard makes me smile

@21:24 .. And for decades I thought I was the only "weirdo" who found certain 'pretty' components simply pleasing to look at and touch.

Hello :) I have some soviet era LEDs :) they are really cool. And some produced in Bulgaria too. During cold war Bulgaria used to produce microprocessors and their first computer Pravetz II. Greetings from Bulgaria.

I noticed as a kid when I listened to my crystal radio in the middle of the night, I could actually see a very tiny feint light coming out of the detector diode. I thought that was cool. Awesome collection!

I always loved LEDs, too. I was enchanted by my aunt’s calculator with the red LED display, and my brother had the Little Professor with a similar display. When I got my electronics kit from Radio Shack I was fascinated by the red LED. I had an active imagination, and looking into it was like looking into another world to me. When I scrapped a VCR or something that had clear LED that put out bright green, it was like I found jewels. I still have those! Then in the 90s when my local discount store started selling blue LED keychain lights, I bought several, along with the red and green, and that was about the time higher intensity LEDs were coming out which were so cool. BTW, I always pronounce it as “led” rather than saying each letter L-E-D, ever since I was a little.

From loving a single dim led to watching the videos of those collections 50 year later on a display made of advance Light emitting diodes is so fascinating :)

I used to have a lot of LED's (early ones) when I was a kid... but none as old as some of these. :D I remember thinking "Why don't they make flashlights out of these?" and i had even made some of my own (probably inefficient) lights from them. Well, here we are in 2017 and every bulb is an LED unless you go hunting for an 'old fashioned' one to be a hipster.

Back on Christmas of 1975 I got a Radio Shack LED calculator. It was the most amazing thing I had ever seen. My Mom had an earlier TI LED unit but mine had FUNCTIONS!

Hi Fran, the first words you said regarding finding LEDs fascinating from an early age totally took me back to when I was about 5 years old and I found a 30 in 1 build your own electronic project kit, I found it at a jumble sale it didn't work I didn't have any other clue about any of the other components but I figured out I could light this tiny little red light when I connected the battery in one particular way! That was the moment and I have had a penchant for taking stuff apart and seeing how it works ever since! I didn't know or understand any of the other components but at the time I was happy to just stare at this thing for hours! It was at the time the most fascinating thing to look at! ✌️ Of course these days now that I build my own circuits I love LED's because they act as a bridge between me and the user who is reading the information these offer when using one of my gizmos, I don't have to be there, our illuminated friends show what users have to do! Love your show Finally 16:55, they don't make them like that anymore tis a thing of beauty. Kind regards Warren

I don't know why I am watching this at three in the morning... anyways, very interesting lesson about leds so... thumb up! 21:39 - I'd make a ring, or a pendant out of it - it's so beautiful!! and there's something for you: once I stole an led from the place where I work. There were some leds every now and there, over some doors, maybe for emergency/fire signalling purpouses, I don't know because I've never seen one light up (fortunately, you might say). Some doors had a green led on, some had one yellow and one green, and some others a red one too. The fact that caught my attention was that those leds were HUGE - I mean, each led was like 3 cm in diameter. So I disassembled three of them (I used them as a mod on a computer case), and the strange thing was that each led had a GND connector plus 2 or 3 other pins, and connecting more pins, the led got brighter... don't know if you ever stumbled upon them.

When blue LEDs were starting to become a reality, I was so excited. Finally RGB can be created with LEDs. Then I saw one and decided it was a really annoying colour for an LED. Suddenly they were the new power indicator for everything and I was bathed in a horrible piercing blue glow in my living room. I stripped them out and replaced them for other colours. So disappointed!

This video is heaven. I've always felt the same way about LEDs. As a kid Radio Shack was my second home mostly because of them. I would buy them and stick them in things with dead watch batteries which still had enough power for them any chance I got. At a summer camp we were supposed to draw a picture and stick the little ornament incandescent bulbs in them and I brought some LEDs from home and used those instead haha. Then as an adult when automotive LEDs started becoming a thing I replaced every single bulb and light fixture with LEDs. Then when LED light bulbs kicked off replaced every single bulb in the house with LEDs. LEDs are amazing! Instant subscriber!

@Fran Blanche If my memory serves me correctly, that TO92 IS actually a working transistor. It would light up to indicate the transistor is in use. I had my hand on a few of these back in the late 80's.

I have tens of thousands of leds here. They are amazing little devices. It is a wonder that I don't have "led poisoning", considering how often I use these in projects :) .

I remember in the year 1986 I hold in my hands the first led I had seen in my life, I was amazed from this kind of technology.

This reminded me of 1983 when I finished a college project firing audio sound via a IR LED at 980 nm - I managed a signal to noise ratio of 90dBm ...amazing how Columbia Uni and their band gap research have created the super bright LEDs we have today. Nice 1, Fran

You are a true treasure! I can only imagine you as a friend , I would want to listen to you talk for hours .

Around 1970 I bought a bag of red LED's from one of those 'Bi-Pak' type of suppliers. They were so dim they were useless for anything except status indicators in a darkened room. Turning up the current didn't make any difference, they just sat there laughing at me. Then came the (just about) usable 'standard' LEDs and then the super-bright and ultra bright, which could actually shine a beam, but the biggest shock came when the genuinely high power types arrived. These were rated in watts and a few years ago a friend and I had great fun with optical voice comms over 3 miles using these LEDs and lenses to form tight beams. Since then, the really dedicated chaps have achieved ranges up to 100 miles.

I remember making a pulsating LED display in the mid '90s and wanted something spectacular in the center: a blue LED. It cost $20 and had to be ordered into the local electronics store (remember those?). Two weeks later it arrived and everyone in the store gathered to see it. And at that point I found out that it needed a good 5V or so to light. Which meant adding a 2N3904 on the back of the PCB and drilling some extra holes to drive the blue LED separately.

I was born in soviet union and my father used to be an electric engineer. He had lots of military-grade soviet LED's that I used to play with when I was a child. And gosh, they were so cool. They werent terribly bright and didn't have any fancy colors, but their build quality and robustness were just over the top. Marvels of overengineering: tiny metal casings, super-fine copper wires with fiber-reinforced heat-resistant insulation, glass lenses instead of plastic, glass potted, etc. I'm sure you'd love them.

Thanks Fran. 8 years later. Nothing is EVER wasted. I like your Digg.

"i'm the operator with my pocket calculator" a quote worthy of the time. i had a Ti unit ;-)

Hey Fran you have taught your cat to `Meow` when you say the word `De-bouncing!" how cool is that ! whoop whoop !!

Fran, I can't believe you can hold onto stuff for such a long time. I envy your ability to re discover these treasures again and again, that must be truly exciting!

Thanks, Fran. Brought back some memories. I still got a few of those, some in metal cases with clear tops. I had an early 1970's 1 w red led with domed top with a gold solder tab on a side and a 6-32 bolt through the bottom to heat sink it. I used that as a nosecone light on a model rocket in the early 1970's. It is mentioned in my model rocket video.

I’m a kid of the 80s, and I was first pulled into electronics by those blinking red, green, and yellow lights. The PlayStation 2 with its blue LED blew my mind. And now I use thousands of them in stage performance projects, so I guess the love of them stayed with me too.

Years ago ( late 80s to early 90s) I modded several guitar pedals with the addition of LED indicators to indicate when the pedal was turned on, as well as changing out the stomp switches for true bypass when turned off. The LED would also dim slightly as the battery became weaker, a nice feature to have.

In the VW model T3 (1979-1992) there was a blue upper beam indicator light in the dashboard. The indicators for oil, battery and blinker were all LEDs (red, red and green) and in early vehicles the upper beam inducator was a yellow LED, but at least in Germany this indicator has to be blue and so in later versions they had to change that yellow LED for a little lightbulb with a blue cap. When I was little (~5 y.o.) I was always fascinated that they had a blue LED in the dashboard of such an old car. That was around 2000 when blue LEDs just got commonly available. It was a very nice cream blue, almost like a baby blue. I used to hunt that color LEDs in every electronics catalog I could get my hands on. Conrad, Mouser, Buerklin, ... It was when I was looking for it in a replacement parts catalog for the T3 when I found out I had been fooled that entire time.

"Happiness is a 10lb bag of seven segment LEDs" - ah Fran, thats adorable in a way only us nerds can relate. Thanks so much this was a great video taking me back to my project days when radio shack sold stuff that you could make entire electronic projects with from the ground up. I always wondered about what was different about that emerald green LED, I had those and looked for them rather than the hazy green ones because I thought they were so much cooler in my projects that needed LEDs.

I worked in a stereo repair shop for the past 16 years; it was extremely rare to see an original LED (stereo indicator etc) die out, but I worked on a Kenwood receiver with a dead LED in the tip of the dial pointer, secured with the same corrosive glue used to hold capacitors to the PC boards. It was a bitch to remove all that glue from the wiring channel of the pointer, and although we had hundreds of different LEDs in stock, even the smallest red LED I could find was just a little too large and I had to file away some of the plastic from the sides of it so that it would fit. It is now very common to see refurbished vintage stereo receivers on RU-vid where the original incandescent lamps have been replaced with LEDs. Although we frequently did this on our own customer's equipment, the problem we often encountered was that LEDs typically emit nearly all of their light from the tops and very little from the sides, as opposed to an incandescent lamp where the light emission is much more omni directional. We often found ourselves setting the new LEDs farther back so they wouldn't "beam", or adding various translucent materials, color gels, replective aluminum tape, parchment paper and so on in order to diffuse the light and get a good color spectrum, as well as using additional resistors to lower the brightness. The majority of refurbished stereo quipment that I see on RU-vid have non-original LEDs that are way way way too bright, with "hot spots" and beaminess for the function indicators and the tuning-dial back-lighting. The other problem we occasionally encountered is that sometimes the current draw of the lamp, or the non- linear resistance of it, would be part and parcel of a certain circuit, such as the multiplex circuit and the stereo indicator lamp.

I love the sight of a 1970's era LED refracted and reflected through a faceted plexiglas bezel! A friend of mine (Tullio Proni) and I both made LED pendants for science fiction fans with plexiglas fronts, mirrored plexiglas backs, with small batteries and circuitry behind. We used 555s, LM3909s (invented by Carl Kleiner, another SF fan), or XR-2240 (?) sequencers. About the same time, I got an HP-35 calculator for college. With friends, we played with those LEDs dunked in liquid nitrogen, cranking amps of current through them, until they became plastic-emitting diodes :-) Fond memories. Thanks for your great RU-vid series. Happily subscribed.

Thank you thank you thank you... for the trip down memory lane! I am 51 and got into electronics when I was about 10 years old. I took my dads super expensive Sharp handheld VFD calculator apart and ruining it. I wanted to see how it worked. At the time, it wasn't "good" for me but in the long run it solidified my love of electronics and later digital electronics that move into the IT field that I am in to this day. Growing up and always being in the more "Rural" setting, I always scrounged around the roads on garbage day picking up old tv's, radio's and other electronics and stripping the parts out of them to create my parts bins... bins that I still have today. I have MANY of the LED's and numeric displays that you have shown here. I have passed my love of this stuff down to my son. He pushes the electrons around a bit differently and at different levels (he's an electrician) but he has a love of electronics as well. I must dig out my old bins of "stuff" for when he comes over later. We both love trips down memory lane. Thanks again... keep up the GREAT WORK!!!! Tim

I, too, have one of the tiny metal cased Monsanto leds. It still works... dimly. No idea where I acquired it from, it was many years ago. I had no idea it was one of the first available until watching your video, so now I know I have a tiny piece of led history. Thanks Fran. Those early 7 segs used to often fail, I remember advising a colleague to use sockets, the inevitable happened.

I remember as a kid trying to read a book with a single yellow 5mm LED in the 80s, what was I thinking. LEDs were just a curiosity for me until the SMD LEDs such the Crew XR-E blew 5mm LEDs out of the water. A totally different world. The XHP70.2 is currently my favourite LED as it is so efficient.

When I feel down I must remember your outlook. Thanks Fran... wondering at the light emitted from my hand held touch screen.

My ex-'s Dad worked for GE and in 1969 brought home a variety of LEDs which I got to play with. He held a patent on some of the first ones.

Brilliant! I watched this on my QLED TV, cast from my AMOLED phone. There's a Cronixie clock under the TV, I haven't replaced a light bulb in 5 years, my bicycle lights are as intense as car headlights but run for hours on a small battery... so LEDs are pretty amazing.

I too absolutely LOVE LED's. I now use the LED chips- nano and pico size. No lens! Just the chip. (About half the size of a pin head). To see this tiny dot glowing so brightly with virtually invisible wires is simply magic.

I took apart my calculator at 7yo , and was in AWW that the leds were , gray when off , and strikingly red when on , I remember my hand held battery powered florescent lamp made interesting , sounds when placed next to my am radio, so I tried with it with the LED calculator .. Mind blown with a harmony of tones . as I eased drop on the RF sounds a calculator makes .. Very Cool !!!

Hehe! You get the same way I do when I look at old LED displays where you can see the little whiskers to the dies. Just so awesome.

When I was 14 years old, I was a fanatic of electronics, I told people that why dont fabricate Monitors based on LEDS i mean dots per inch was alrady there, pixels etc, we could use leds for that.. people laughed at me... today... we have LED TVs :-p Here is how you destroy masterminds, now i am just a lousy filmmaker hahaha (here again, i talked about several cameras before the matrix effect was discovered), again... people laughed :p now we have 360º Cams :p lol

Your video was Frantastic!

Wow. i had a Novus calculator in the 70's the model name was the "Sliderule" used it secondary schooling, it was Reverse Polish notation, scientific calculator, had to save for 3 months to buy it. It had the same red led's , and wow to those first leds!!. thanks for lighting up the old ones for us. , even the 70's resistors on your old board was a blast to see again. clear calculator display - i said "work of art" only 3 seconds before you. you have a amazing collection, I really like the those original blues. Felt your happiness at the end. Thank you so much for sharing.

I think a ten pound bag of 7 segment LEDs will always hold the promise of a brighter tomorrow, I know just the thought of it lightens up my spirits! My wish to you is an old Pink Floyd lyric...Shine on, you crazy diamond!!

I learned a ton! I totally get the appeal-some of that early circuitry was beautiful in its own quirky ways unique to their eras. Fascinating to know that the calculator displays rely on a timer and human visual permanence-not the most intuitive solution but it definitely seems to simplify things. I always wondered why old LEDs were always red, now I know! I feel deceived that modern LEDs use UV and phosphorus to “cheat” to achieve their color rather than produce them purely. Reminds me of tube TVs with their phosphorus coating or even incandescent lantern mantles. Still a fun solution in its own way. Thanks for doing these.

I remember the first time I saw a blue LED. I had never seen anything like it - its brightness and colour. The idea was to use it with a type of fax paper to create images of satellite signals we were receiving.

OMG!! I had that *exact* calculator when I was a kid!!! My Dad gave it to me for XMas in 1976!! I was in first grade, just learning the most basic math, and the reverse-polish-notation that that calculator required was so hard for me to understand at first. It was so cool when it finally “clicked” in my head. :-) I wish I knew where it was now...

I've got some DataSAAB 7-segment LEDs (yes, THAT SAAB company). When SAAB decided to do their own jet fighter, they had to start from zero, and make a computer first. The computer was from 1971, with core memory, and it was used at the local bank well into the 80s. We got to take it apart when it was decommissioned, which is where I got the LED from. As far as I know, the majority of the components ended up in someone's model railroad controller.

that one at 21:20 could be a piece of jewellery

Just realized I've watched this at night on an LED-backlit screen, in a room I recently switched to all LED lighting, so pretty much all the light in here came from LEDs...

Hey Fran! I'm 52 and I was into electronics very young, at 5 or 6 years old I was experimenting with components. L.E.D.'s were my biggest interest, you bring back some great memories!

I recently found something funny in my old-parts-bin. A blue "pseudo LED" from the 90s. Because blue LEDs were so expensive and everyone wanted to have them, they made tiny incandescent bulbs that looked like blue LEDs ;) An interesting piece of tech history. I still remember when the Playstation II came out. It was "hot" ... The graphics? No... That thing had a blue LED!

When Radio Shack started selling LEDs they sold that particular Fairchild one (your second example). As you said it wasn't very bright but was fun to play with. I accidentally powered directly from my 6V battery and it exploded. At $5 it was an expensive mistake for a 14 year old kid. Now we have LEDs that can be used as street lamps and car headlamps.

A friend of mine has an old Bridgeport milling machine with power feed on X and Z and the power feed units have first-generation LEDs on them. They still light up to this day, although very dimly; they are used as power indicators.

I like vintage components. When you look at a PCB from the 80s or something, it's cool how you can see each component. If you look at a modern PCB, it's just all green, with a few black ICs.

I bought my first LED in autumn 1968 when I stopped off in London on my way for interview at Kent University. There was a component shop in Tottenham Court Road (name escapes me) that sold the first infra-red LED that I'd seen. It was in a metal case that was intended to be strapped to a heatsink and came with a quartz lens to focus the beam. I was eventually able to transmit a signal across the living room and detect it with a photodiode, but setting up was very tricky as you couldn't see where the beam was.

All these older LED devices take me back to my college days (late 1960s and early 70s) and the various electronic projects I built during that time. Thanks for all the memories!

33:20 "I'm sorry Fran, I'm afraid I can't do that"

The first calculator my Dad brought home sometime around 1972 was a Texas Instruments "Datamath". I just looked it up and found a picture so I could confirm the model name. I only knew it was so expensive he had to lie to my mother and claim he "found" it. It had a display just like yours but it was about 3 times as thick and was loaded with at least a hundred discrete components. It seemed like it weighed a pound. I think it was at least 1 1/2 to 2 inches thick. Only after years went by it got dropped and was no longer working did I dare take it apart to see the hundred or so components. It did have a couple of chips but was literally jam packed with components. Its so funny to see the inside of a modern calculator when everything is on one chip.

Informative as all ways! I think it was back in the 1990s, Siemens had some ads in the most common technology magazines for engineers where they ask the readers for the need of blue LEDs. It seemed, they saw the huge amount in investments to develop these.

I used to like the bags of unmarked transistors, but I totally get the 'bag of led's' thing as well. Cool.

Thanks Fran. I love 'em too! We sure have seen some remarkable developments in our days.

In the past, I have collected a bunch of white leds and I have no idea where they are to this day but I might get a box of colored leds for my birthday. I am a fan this technology and probably will be for the rest of my life to come, awesome collection!

Like the "crazy cat lady" but with LEDs. ME TOO! I have some going back to the 1960's that barely emit light but they do! In 1973 my great uncle gave me a TI calculator that did add/subsract/multiply and divide with no memory and came in a "leather" case. It ran on 4 AA batteries and I think he paid over $100 for it. I was taking Algebra and he thought it might be useful. I still have it and it works.

I'm 73 and I admired LEDs from my first contact with them. You are amazing and one of rare woman, who deals with electronics. Thanks for your input, I loved it.

While still in school I had an interest in optical communications. When LEDs first became available I purchased one. It came in a cardboard box about 100 x 100 mm packed in shredded paper. It cost nearly a weeks wages. At last, a decent data rate. :)

My father had a Bomar Brain calculator from the early 70's. My memory is that he got it at Sears, he was very impressed with this gadget. I got it in the 90's and replaced the battery with another rechargeable and rewired the socket that matched a charging adapter. The last time I tried it it still worked. I also remember the first electronics kit I had that had a led light. I remember the first green led I encountered in a control board in a film processor, that was in 1981.

I thought I was the biggest fan! I even replaced the green led in my PlayStation 1 to a blue to be the coolest one out there. Well now you have me looking for those to-92 ones. Thanks and cool video.

I purchased a set of 10 LED digit display project parts from RadioShack back in 1975 I was just fascinated that a almost microscopic light could be shaped so compact unlike tiny heat prone incandescent lights of the same period. I never would of thought LEDs could do all the cool things they do today.

Hi Fran. I did my own self learning about the same time as you - late 70's early 80's. I had two 32 drawer bench parts cabinets stuffed to the brim with LEDs of all sizes and shapes. By the mid 80's most of commercial electronics was moving to LCD displays and LED manufacturers were trying to unload their stock. You could buy huge bags of various LEDs for a couple of dollars. The intrigue was sorting all the LEDs to their individual drawers and imagining some project where they could be used. Interestingly, in one bag of "micro displays" was a 12 digit, 17 (I think) segment, multiplexed tube display. Now THAT was a work of art! I presumed from the gold contacts and connectors inside the tube that it probably was manufactured for a military application - probably cost Uncle Sam several hundred dollars a unit and here it was in a grab bag for a couple of bucks! I found it so intriguing it drove me to learn how tubes worked. I'm surprised you did not show a tri-color LED; +/- = red, -/+ = green, alternating = yellow. These two element LEDs were a mystery to me until I later learned about RGB video displays and that mixing red and green light makes yellow. TO-92 LEDs - at the time of my self schooling I worked for a residential alarm company. The system used FM radio to connect the various sensors to the main control and most of the sensors were housed in plastic boxes stuck to windows and doors. To prevent tampering the sensor used a TO-92 red LED and an IR sensor separated by a thin tab of plastic in the case top. If the top was removed the IR sensor would "see" the LED and complete a trigger circuit. The TO-92 package for both devices meant it could all be mounted directly on the PC board. I know that several early models of HP printers used this arrangement as a paper sensor.

I bought a string of LED Christmas lights from Home Depot 10 years ago. It had 1 lamp that had a green epoxy package, but a blue LED chip inside. The rest of the set was correct. Regardless I kept that string on 24/7 up until 2013, and all the lamps still worked well. Then I sold the house and lost the string.

funny how I found this video today... I found a ton of old Christmas string LED lights that were no longer working.... time to yank them, test them, sort them and save a ton of money. They will come in handy for sure. Your videos are electronics ASMR!

Back in the 70's, I bought one of those at a TG&Y five-and-dime. If memory serves, it had a *fixed* decimal. If you put it next to an AM radio, the radio would make a lot of noise.

My first LED was one of the second one you showed.(circa 1972) Yeh, it was dim. I tried putting a lens in front of it and focusing a spot on the wall which could only be seen if the lights were turned off. Later experiments with LEDs of the late 70's I was able to use one to send pulsed light a few feet to a photocell hooked up to my o-scope(without using lenses), altho it was rated at 50ma, the pulses peaked at one amp. The pulses were so short you couldn't see them. And if the rep rate got too high, it would burn it out.

Most of my LEDs are the very cheap modern ones that you get by the truckload, but I have a few older red ones (by which I mean, about 10 years) that were more expensive. The difference in the light quality is very noticeable. The cheap ones are very efficient, very bright, but a little harsh and with poor diffusion, the die is very obvious. The older red ones I have have much better diffusion and are a deep, cherry red. Lovely to look at, they can be stared into without any discomfort.

Wow, brings back memories from my childhood. The spine-tingling sense of exploration came back for a second.

Sorry you’re feeling down, hang in there kid! I love those little dome 7 segment displays, reminds me of my TI SR-40 calculator I used in electronics school. Love your collections...

The 3-legged TO-92 'LED' is, I believe, a combination LED and phototransistor. These were used in the old ball mouse to sense the wheels turning or to sense something passing by the LED/sensor.

"it's beautiful" *It is hard to argue with that assesment*

The first LEDs weren't even actually LEDs. They were just normal diodes. Then someone realized they emitted faint light when biased. That's what started them down the road to the LED we have today. If you get some cheap diodes with glass bodies, you can often still find some that light up when biased.

It's amazing to think that I was buying those very same horribly expensive blue LEDs because I thought they looked AWESOME. I still can't resist a few more pretty LEDs in my project than I really need. OneI havent tried yet is the UV blacklight LED (Not to be confused with rhe dangerous deep UV LEDs for those newbies playing along at home). Thanks for putting it out there again Fran.

It's nice to see that I'm not the only person who is romantically involved with LEDs. If Fran can have a LED fetish, so can I. Which I do. I guess I have to order some more of those ultra-bright UV LEDs now ...

Thanks to the success of your clips on the BINA VIEW, the algorithm brought us the video of your amazing collection of old LEDs! Double thumbs up for this!

I was born in 1997 but even when I was very little I was interested in technical things and my dad made me aware of LEDs, and I took note of the range of colours that existed. Vividly remember the first time I saw a blue LED, my uncle had bought a new desktop PC in the early 2000's and it had a tiny one for the power on LED in the case. I actually sat in front of it for a while just to look at that almost unnatural light. I also have collected them but only as far as I've been able to desolder them from things over the years mostly. I wanted to purchase some of the red ones in the transistor package at the end from the one website that had them in stock but of course, this was in 2020 and they weren't shipping overseas, they sold out in the meantime. Most interesting one I think, besides old 7 segment displays, would be a green 'play button' shaped one. Maybe it's cooler in my mind because it was the last in stock at an old electronics shop (it was actually glued to a display board) and when I asked about it the guy in the counter pulled it out from the board and gifted it to me.

I have toyed with LEDs since the late 80s. I was also quite fascinated by them, though not as much as you :) I remeber getting my hands on a 3 pin LEd, somewhat like that gold-plated, transistor shaped one, but it used to light up well. It had two different colors built in one (this was awesome considering it was in the late 80s) and hence the three pins. All in all, awesome stuff you got there. Your video is bookmarked :)

I been collecting them all my life as well, I have hundreds. Those MV1"s have a glass bead in a brass cup, I still have a few. SONY used them as dial indicators in early 70's transistor radios such as the TFM-8100W. Love your videos, keep up the good work.

Theose early LEDs all so beautiful and jewel-like - and antique. I'd love one or two of those in my box... actually, I'd probably frame them! In lieu of that, this is a great video, Fran - thank you!

Oh, I forgot to say that as a kid I could not understand why a single battery (1.5V cell) would not light my LEDs. Later I learnt about the I/V characteristics. I know you did sort of mention it but it is amazing how many people don't realise that on non- phosphor LED's the case is not what gives it the colour but the specific photon wavelength from the quantum drop in the semiconductor junction. In some with colourless cases (encapsulations) even the phosphor ones give no indication of colour until turned on. Quite cool really and very different from a coloured light bulb!

Hey Fran nice collection of classic LEDs - I have always been an LED lover myself - my first accomplishment was lighting up a MAN5 7 segment display when I was a young teen in the 70s. The LEDs back then were not as bright as today's. It's amazing now all the colors and varieties of LEDs and displays that are available. I remember when orange and amber were introduced, then green, then blue, then white...now we have UV and have had infrared a long time. BTW my first calculator had those tiny multiplexed displays (it could do % calculation - WOW) - I wish I had saved it! I remember one of the first TV ads for the "BOWMAR BRAIN" calculator!