Oh, now those ARE interesting. That construction and 3D printing could allow for very custom displays. The thick leads are reminiscent of the high current 5mm LEDs used in some flashlights.
Clough42 just covered 3d printing custom 7-segment displays with a 2 material extruder printer. He got some pretty nice results. And his tests were based on another channel that I saw the original video of, but forgot who it was now. The guy that builds the 3d printed modular parts counting system that fits into plastic storage bins.
Hi Clive, such 7 segment light guides are still available today, to combine them with SMD LEDs of your choice. I commented earlier on that - just search for my comment. I think it was Mentor who is making these...
I was an electronic tech in the steel mills back in the 70's. We had controls that used mechanical readouts that were controlled by BCD. They were very unreliable and the operators would have to pound on the control panels to get the readouts to work. We replaced those readouts with these same Dialight readouts in red. They worked great and the operators loved them no more pounding. Power consumption was not an issue as these controls had massive power supplies and the led displays actually used less current than the mechanical ones. This brought back some old memories.
Agreed, back then being used to the current consumption of most electronics at that time, and still evolving out of the "tube" era, these were perceived as current efficient for the most part. Pretty much anything LED was considered current efficient.
Fran, here's a tip for a safe pin header power supply pinout. Use three pins, outer two are ground and the inner one is power. That way you can insert it either way and not let the magic smoke out.
I think Hewlett Packard had made one of the biggest LED BCD Displays in this time. The HP 5082-7500 was the huge version of the 5082-7010 LED Display. It used instead of the small LED Chips in the 5082-7010 regular 5mm LEDs to create a 1.5 Inch high Display. They are very rare today.
Shudder to think at how much one of those LEDs must have cost in 1975. Even by today's standards those LEDs aren't bad -- they seemed to hold up to your video lighting just fine.
...and a joy for ever. The transitional tech is somehow fascinating. It shows the evolution of tech, partly reminding me of the early generations of photo-typesetting machines which were based on the old and well known hot metal typesetting gear. Beautiful light indeed!
"S" logo on the 7447 BCD to 7 segment chip is Signetics, most famously known for the 555. Philips took them over in the 70s. I was making stuff with 7447s in 1977 when I was 12, when I designed and built a TTL clock, with about 20 TTL chips. It took about an amp at 5V! It was controlled by the line frequency, so when the washing machine ran it would count up hundreds of seconds when the machine's cycle changed ;-) You could always tell when a 7447 or 7448 was being used in an application because the top of the 6 and bottom of the 9 were missing. Possible application is gas pumps, although the first digital pumps I remember used 7 segment incandescent filament displays.
As for the lack of tails on the 6 and 9, if you want a tail on 6, you can use an and gate, inputs connected to BCD lines driving 2 and 4, and for a 9, connect and and gate to bcd lines 1 and 8. Then connect the outputs directly to segments D for 9 and A for 6. I've done this in a clock I built to get the tails with a 7447. Ie, the and gate connects along with the 74ls47 or 7447
@@devicemodder I recall reading that the lack of tails was intentional, to minimize the chance that a failed segment could lead to one digit being identified as another digit. If you lost a segment from an 8 you could think that was a 9 or a 6 if they had tails, but not if they're tail-less. With these being intended for mil applications, I can believe that. The fact that it saved a couple gates probably played a part as well.
@oscar_charlie makes sense to me. Just personal preference when I made my clock to have tails. Now, I use a clock on a chip from the 70's and various logic depending on display type I'm driving.
Beautiful color and really interesting construction, using discrete LEDs with light guides is kind of ingenious. And the digits are really quite big. And "just" ~5 decades later we have the tech available to DIY 7-segment displays almost as big as we want, still run by LEDs xD (built myself a giant 7-segment clock with 3D printed frames, WS2812B LED strips, driven by python code running on a raspi. Each digit is almost 21cm tall)
I got the displays themselves and still have the red versions in my home brew frequency counter, still working. I actually drew the board patterns with a resist pen.
Wow brings back childhood memories when I used to play with these 7 segment displays in the mid-70s. I used to get them from Poly Paks (to save my precious allowance money!). Todays LEDs are more efficient so you can probably get down to 10-15 mA per segment with a choice of various colors which weren't even invented back then. It would be interesting to retrofit that PC board with modern LEDs. Those old TTL chips were power hungry too but could source or sink a lot of current per pin. S logo was for Signetics which was defunct long ago. Another idea - you could 3D print that LED housing and front to make your own super displays (just for the fun of it). My first project involving MAN7's was the infamous "Son of a Cheap Clock" kit I bought for something like $15 back then - came with PCB, clock chip, resistors, transistors, and other active parts, but no case - I got that in Radio Shack locally at the time.
That was AMAZING!!! I now completely understand LEDs. Your custom driver is spectacular, as is your One-Fran-Funk-Band soundtrack. LOL! I wonder if those 2 letters on the board were the board makers's mark? Now I know how my classic 70s bedside Philips clock-radio's red LED display works. 'Pipes'... you're simply amazing, Fran, Steph 🙂
About 20 mA for a single 5mm LED is not particularly high until quite recently. All the way through the 1990s this was the standard current for indicator LEDs. Nowadays with multi-quantum well structures and InGaN LEDs you get the same brightness from just a few mA, but even your MAN72 were specified for 240 mA total continuous forward current with all segments lit - even higher when used in multiplexed displays.
Indeed. I made a similar comment. Right up until the modern era of "ultra bright" LEDs (late 80s to early 90s, IIRC), it was usual to specify 20-25mA per LED, which was also the recommended range in the LED data sheets. Speaking of multiplexed LED displays, I once did a workbench design where I took advantage of it to eliminate the usual current limiting resistors, relying on what was effectively PWM to reduce the per-LED current to a safe level.
awesome vid and info ~ ! and well now i feel special i played with these found in some parts bin in electronics class in highschool only they were red im sure they were the exact same aside from you know red colored leds used to have them connected in line with speakers on my awesome teenage hifi LOL anyways this made like a color organ thing lights to the beats ! annnd i figured out that both the left and right channels could be connected to the one panel i had two YAY ! anyways with both left and right stereo lighting the different sections it created some pretty neat lights shows to smashing pumpkins and the like brought back some kewl memories and i will revisit that experiment again someday so thank you fran
MC = Monsanto Company - Wikipedia: In 1968, it became the first company to start mass production of (visible) light-emitting diodes (LEDs), using gallium arsenide phosphide. From 1968 to 1970, sales doubled every few months. Their products (discrete LEDs and seven-segment numeric displays) became industry standards. The primary markets then were electronic calculators, digital watches and digital clocks.[47] Monsanto became a pioneer of optoelectronics in the 1970s.
I remember seeing a 7 segment LED display that color somewhere but I can't place it. I believe it may have been the channel display on the Zenith TV we had when I was young.
I remember visiting most of our local Marconi GEC factories in Essex(long defunct), whilst studying Physics and Electronics at school in 1971. Sadly I didn’t appreciate at the time what I was seeing, and just took it for granted. We were at one plant where a lady was demonstrating an LED display, and mentioned that they were produced using sputtering, presumably to get the very thin layers needing for light transmission. Obviously these were not production devices, and would have been hugely expensive. The first practical devices would have found their way to the military for use in such things as HUDs I assume. This was at a time when the first affordable single leds were making their way on to the market.
that S on the ttl chip is for signetics , korean firm bought by philips/mullard in '75 the other chip is likely painted and remarked by dialco,, the style of the moulding looks a bit national semiconductor
Hey, high, hello Fran, I can't afford a pedal at the moment but I (and surely others) would love to rock some Fran stickers on instrument cases, buttons, but more importantly GIANT BILLBOARDS. Cheers!
Cool displays for the time! Pun intended! Large displays were always nice for digital clocks in the 70s, and they came up with many different ways to make them! Finding the exact replacement displays is a difficult job, but due to the many flavors, a substitute isn't difficult! Which makes restoring things a tad bit easier!
Odd to me that nobody was doing them larger from day one. Once the single package diode was out, there should've been at least two or three packages on the market for even larger units. Once you have the LED driver figured out you're set. Light pipping is easy, even in that era. Not cheap, but then again, nobody would use these for cheap devices. Pop in Two LED bulbs for a segment and you could easily double the size. Must've been so fresh, so new, that nobody considered it or the other thing that usually stems/narrows these things. Production, or rather how many of these LEDs made their way into engineer hands.
Are there any modern (in production) equivalents of those "bubble display"s? I have a project where I need tiny 7-segment displays (curernt displays beside each USB port). But those "bubble display"s have become expensive collectible "historic artifacts".
I used those exact units by Dialight in tank gauge display decoder i built while working for Big Oil. Our pipeline terminals had Varac tank gauge decoders. The gauge units had a 14 bit gray code to represent feet, inches, and parts of an inch. I used 7400 series chips to decode and display the tank level to the operator. All storage tanks have a chart that converts level to volume in the tank. It was a good project that was all wire wound IC sockets. I am now 72 and retired for many years. Those gauges were all replaced with either radar or servo units. Take care Fran.
Wow that's really cool, maybe they were supposed to really be more reliable? I remember well the slow march of LEDs out of the 70's, the 4 bangers, the clocks, the Caleco football, the audio gear, the RadioHack catalogs! The only one I hated was the more recent blue phosphors, still a scourge haha. I still recall being impressed by the first "white" LED penlight I saw around the turn of the century. Truly remarkable how far we've come.
Each segment looks uniform even though there's only one LED! I'm trying to make bigger 7 segments LED, about 60mm height with filament LEDs. I can buy ready made ones but self made cost less ;-)
I am guessing that these might have been used in larger copier machines (the type used by printing companies and commercial print shops), medical devices, military control panels, aircraft, or industrial machinery. Commercial timing or temperature controls may be a possibility as well. Some laundromat machines might use such displays to display the number of minutes remaining. I also wonder if they were used in the remote controllers for scoreboards, race clocks, and things like that.
I am also guessing that these type of displays could have been used for the clock and timers on some podiums used by lecturers, board rooms, courtroom witness stands, and similar applications.
You can make excellent light pipes from hot glue. I was thinking that you should do a video on the very earliest "Price Is Right" displays when the first items went up for bids and they used digits made from 35 (7x5) light bulbs each segment. For what ever reason they changed over to their own green and orange seven segment displays by 1974. They still used the light bulbs in other parts of the show, such as the showcases however. Thanks for being the "Queen of displays"!
Can remember horrible Nixie tube displays back in the 1960's. Forget what first digital displays that small hand held calculators used but think it was a 9 volt battery did not last more then 10 to 15 hours.( guys I was in high school with used the very small calculators to cheat on math test back around 1968 ).
I don't know why but I've always found green the least interesting LED colour. It's not that I don't like the colour green but with LEDs it's always this pale yellowish green colour that's not very pronounced. My oven and microwave both have a green LED panel and I've even thought about opening them up to change them for red LEDs 😂
I am the opposite, I always liked green and yellow 7-segment displays better than red ones. Except the red TIL 306 - 308 and especially 311, those are my favourites, but they are too tiny for a desktop LED clock.
Oh, now those ARE interesting. That construction and 3D printing could allow for very custom displays. The thick leads are reminiscent of the high current 5mm LEDs used in some flashlights.
Still pretty tiny for most 3D printers, though I did this other project years ago just for printing - czcams.com/video/M3jyMX8EXAQ/video.html
Clough42 just covered 3d printing custom 7-segment displays with a 2 material extruder printer. He got some pretty nice results. And his tests were based on another channel that I saw the original video of, but forgot who it was now. The guy that builds the 3d printed modular parts counting system that fits into plastic storage bins.
I found him, Christopher Helmke is the guy that was originally doing 2 material integrated segmented displays in 3d printed front panels
Why do i feel like you might be printing out some light pipes and building a custom set?
Hi Clive,
such 7 segment light guides are still available today, to combine them with SMD LEDs of your choice. I commented earlier on that - just search for my comment. I think it was Mentor who is making these...
I was an electronic tech in the steel mills back in the 70's. We had controls that used mechanical readouts that were controlled by BCD. They were very unreliable and the operators would have to pound on the control panels to get the readouts to work. We replaced those readouts with these same Dialight readouts in red. They worked great and the operators loved them no more pounding. Power consumption was not an issue as these controls had massive power supplies and the led displays actually used less current than the mechanical ones. This brought back some old memories.
Agreed, back then being used to the current consumption of most electronics at that time, and still evolving out of the "tube" era, these were perceived as current efficient for the most part. Pretty much anything LED was considered current efficient.
I can't remember running into LED displays of that size until the early 80's. That they were around in the mid 70's astounds me.
I have vague memories of seeing this type of display in NASA's Mission Control Center in Houston.
Fran, here's a tip for a safe pin header power supply pinout. Use three pins, outer two are ground and the inner one is power. That way you can insert it either way and not let the magic smoke out.
Is it weird that I think that this looks beautiful?
Not at all!
No, I think most Franlab viewers are probably of the same mindset and will find this nice.
Stunning colour!!!
Makes me wish I still had my box of vintage 70-80s LEDs, I have no idea what happened to it.
I had a few lots of vintage LED's saved in my eBay history but I never bought them, I should look again.
Yeah, who ever thought back then that those parts would be sacred in 2020.... I also have so much of that stuff lost in moves across the country....
I really enjoy your vintage 7 segment display "showcases".
That is quite a vibrant "citrus" yellow green.
It is an unusual shade.
I think Hewlett Packard had made one of the biggest LED BCD Displays in this time.
The HP 5082-7500 was the huge version of the 5082-7010 LED Display.
It used instead of the small LED Chips in the 5082-7010 regular 5mm LEDs to create a 1.5 Inch high Display.
They are very rare today.
Shudder to think at how much one of those LEDs must have cost in 1975. Even by today's standards those LEDs aren't bad -- they seemed to hold up to your video lighting just fine.
These look really easy to replicate for the home hobbyist. Just a little PCB design and some 3D printing.
Modern hobbiest can get much better LEDs, too.
Old tech reminds me how far we've come.
...and a joy for ever.
The transitional tech is somehow fascinating. It shows the evolution of tech, partly reminding me of the early generations of photo-typesetting machines which were based on the old and well known hot metal typesetting gear.
Beautiful light indeed!
Be cool to see the stripped down one running to see what those LED's pure light output looks like.
A very lovely and interesting LED display. Much more interesting than later seven segment displays.
I believe the 'S' logo from the second driver belonged to Signetics corporation.
"S" logo on the 7447 BCD to 7 segment chip is Signetics, most famously known for the 555. Philips took them over in the 70s.
I was making stuff with 7447s in 1977 when I was 12, when I designed and built a TTL clock, with about 20 TTL chips. It took about an amp at 5V! It was controlled by the line frequency, so when the washing machine ran it would count up hundreds of seconds when the machine's cycle changed ;-)
You could always tell when a 7447 or 7448 was being used in an application because the top of the 6 and bottom of the 9 were missing.
Possible application is gas pumps, although the first digital pumps I remember used 7 segment incandescent filament displays.
Beat me to it by 5 minutes.
They also "made" the 25120 9046-bit Write-Only Memory.
As for the lack of tails on the 6 and 9, if you want a tail on 6, you can use an and gate, inputs connected to BCD lines driving 2 and 4, and for a 9, connect and and gate to bcd lines 1 and 8. Then connect the outputs directly to segments D for 9 and A for 6. I've done this in a clock I built to get the tails with a 7447. Ie, the and gate connects along with the 74ls47 or 7447
@@devicemodder I recall reading that the lack of tails was intentional, to minimize the chance that a failed segment could lead to one digit being identified as another digit. If you lost a segment from an 8 you could think that was a 9 or a 6 if they had tails, but not if they're tail-less.
With these being intended for mil applications, I can believe that. The fact that it saved a couple gates probably played a part as well.
@oscar_charlie makes sense to me. Just personal preference when I made my clock to have tails. Now, I use a clock on a chip from the 70's and various logic depending on display type I'm driving.
@@devicemodder I agree, I like the digits with tails. I think later flavors if the 7447 implemented them.
Beautiful color and really interesting construction, using discrete LEDs with light guides is kind of ingenious. And the digits are really quite big.
And "just" ~5 decades later we have the tech available to DIY 7-segment displays almost as big as we want, still run by LEDs xD
(built myself a giant 7-segment clock with 3D printed frames, WS2812B LED strips, driven by python code running on a raspi. Each digit is almost 21cm tall)
Signetics I think, not Sigma. Later Mullard and then Phillips.
Yep. Makers of the 555 timer and the 25120 9046-bit Write-Only Memory.
Interesting. A funny thing - my new 'state-of the art' microwave/grill/oven/air frier has an oled display that mimics the LED displays of the past.
Thank you, Fran. This is so cool! 🎉😍 Thank you for sharing this awesome content. My oldest LED is from 1980. Can't wait for more videos like this. 👏
I got the displays themselves and still have the red versions in my home brew frequency counter, still working. I actually drew the board patterns with a resist pen.
Wow brings back childhood memories when I used to play with these 7 segment displays in the mid-70s. I used to get them from Poly Paks (to save my precious allowance money!). Todays LEDs are more efficient so you can probably get down to 10-15 mA per segment with a choice of various colors which weren't even invented back then. It would be interesting to retrofit that PC board with modern LEDs. Those old TTL chips were power hungry too but could source or sink a lot of current per pin. S logo was for Signetics which was defunct long ago. Another idea - you could 3D print that LED housing and front to make your own super displays (just for the fun of it). My first project involving MAN7's was the infamous "Son of a Cheap Clock" kit I bought for something like $15 back then - came with PCB, clock chip, resistors, transistors, and other active parts, but no case - I got that in Radio Shack locally at the time.
Your 1PPS was begging to be used for the dot :)
That was AMAZING!!! I now completely understand LEDs. Your custom driver is spectacular, as is your One-Fran-Funk-Band soundtrack. LOL! I wonder if those 2 letters on the board were the board makers's mark? Now I know how my classic 70s bedside Philips clock-radio's red LED display works. 'Pipes'... you're simply amazing, Fran, Steph 🙂
Very nice looking! I would totally exchange this for today's blue LEDs that hurts my eye.
Thats a nice shade of green, and I bet it's better in person.
About 20 mA for a single 5mm LED is not particularly high until quite recently. All the way through the 1990s this was the standard current for indicator LEDs. Nowadays with multi-quantum well structures and InGaN LEDs you get the same brightness from just a few mA, but even your MAN72 were specified for 240 mA total continuous forward current with all segments lit - even higher when used in multiplexed displays.
Indeed. I made a similar comment. Right up until the modern era of "ultra bright" LEDs (late 80s to early 90s, IIRC), it was usual to specify 20-25mA per LED, which was also the recommended range in the LED data sheets. Speaking of multiplexed LED displays, I once did a workbench design where I took advantage of it to eliminate the usual current limiting resistors, relying on what was effectively PWM to reduce the per-LED current to a safe level.
I love this color green 🍏
Old green LED is best green LED :)
bet those beauts were expensive in '75
I think that the S logo is for the chip maker Signetics.
12:45 - I'm guessing they went to green LEDs, since MUCH less fatiguing on the eyes than RED!
Nice displays. I love the LED colour.
awesome vid and info ~ ! and well now i feel special i played with these found in some parts bin in electronics class in highschool only they were red
im sure they were the exact same aside from you know red colored leds used to have them connected in line with speakers on my awesome teenage hifi LOL anyways this made like a color organ thing lights to the beats ! annnd i figured out that both the left and right channels could be connected to the one panel i had two YAY ! anyways with both left and right stereo lighting the different sections it created some pretty neat lights shows to smashing pumpkins and the like brought back some kewl memories and i will revisit that experiment again someday so thank you fran
MC = Monsanto Company - Wikipedia: In 1968, it became the first company to start mass production of (visible) light-emitting diodes (LEDs), using gallium arsenide phosphide. From 1968 to 1970, sales doubled every few months. Their products (discrete LEDs and seven-segment numeric displays) became industry standards. The primary markets then were electronic calculators, digital watches and digital clocks.[47] Monsanto became a pioneer of optoelectronics in the 1970s.
I remember seeing a 7 segment LED display that color somewhere but I can't place it. I believe it may have been the channel display on the Zenith TV we had when I was young.
Be neat to see some of these in the dark.
I remember visiting most of our local Marconi GEC factories in Essex(long defunct), whilst studying Physics and Electronics at school in 1971. Sadly I didn’t appreciate at the time what I was seeing, and just took it for granted. We were at one plant where a lady was demonstrating an LED display, and mentioned that they were produced using sputtering, presumably to get the very thin layers needing for light transmission. Obviously these were not production devices, and would have been hugely expensive. The first practical devices would have found their way to the military for use in such things as HUDs I assume. This was at a time when the first affordable single leds were making their way on to the market.
that S on the ttl chip is for signetics , korean firm bought by philips/mullard in '75 the other chip is likely painted and remarked by dialco,, the style of the moulding looks a bit national semiconductor
Me encanta toda esa tecnología de aquellos años era una chulada❤❤❤
I'd guess that "Sigma" logo stands for Signetics?
Makers of the 555 timer and the 25120 9046-bit Write-Only Memory.
Hey, high, hello Fran, I can't afford a pedal at the moment but I (and surely others) would love to rock some Fran stickers on instrument cases, buttons, but more importantly GIANT BILLBOARDS. Cheers!
It feels like yesterday.
Nice, looks very similar to the HDSP-37XX displays from Hewlett-Packard...
Cool displays for the time! Pun intended!
Large displays were always nice for digital clocks in the 70s, and they came up with many different ways to make them!
Finding the exact replacement displays is a difficult job, but due to the many flavors, a substitute isn't difficult! Which makes restoring things a tad bit easier!
Odd to me that nobody was doing them larger from day one. Once the single package diode was out, there should've been at least two or three packages on the market for even larger units. Once you have the LED driver figured out you're set. Light pipping is easy, even in that era. Not cheap, but then again, nobody would use these for cheap devices. Pop in Two LED bulbs for a segment and you could easily double the size. Must've been so fresh, so new, that nobody considered it or the other thing that usually stems/narrows these things. Production, or rather how many of these LEDs made their way into engineer hands.
I don’t want to see another eye searingly blue LED on a modern product again, only these!
Are there any modern (in production) equivalents of those "bubble display"s? I have a project where I need tiny 7-segment displays (curernt displays beside each USB port). But those "bubble display"s have become expensive collectible "historic artifacts".
Maybe used for the button panel in elevators ??
I used those exact units by Dialight in tank gauge display decoder i built while working for Big Oil. Our pipeline terminals had Varac tank gauge decoders. The gauge units had a 14 bit gray code to represent feet, inches, and parts of an inch. I used 7400 series chips to decode and display the tank level to the operator. All storage tanks have a chart that converts level to volume in the tank. It was a good project that was all wire wound IC sockets. I am now 72 and retired for many years. Those gauges were all replaced with either radar or servo units. Take care Fran.
And I never had a failure in any of the Dialight displays I used. It was good equipment.
Not quite, the bonding wire is attached to the silicon piece inside the cup :)
nice display. thats a Signetics IC
Wow that's really cool, maybe they were supposed to really be more reliable? I remember well the slow march of LEDs out of the 70's, the 4 bangers, the clocks, the Caleco football, the audio gear, the RadioHack catalogs! The only one I hated was the more recent blue phosphors, still a scourge haha. I still recall being impressed by the first "white" LED penlight I saw around the turn of the century. Truly remarkable how far we've come.
Each segment looks uniform even though there's only one LED!
I'm trying to make bigger 7 segments LED, about 60mm height with filament LEDs.
I can buy ready made ones but self made cost less ;-)
I am guessing that these might have been used in larger copier machines (the type used by printing companies and commercial print shops), medical devices, military control panels, aircraft, or industrial machinery. Commercial timing or temperature controls may be a possibility as well. Some laundromat machines might use such displays to display the number of minutes remaining. I also wonder if they were used in the remote controllers for scoreboards, race clocks, and things like that.
Maybe vending machines?
The first large led displays I remember seeing were in the mid 1980s...
I like that green, though I can't say how accurate my PC/monitor is. Somebody out there has to recognize such a great color.
i remember these on laundromat units
Philips made an even larger one for their color TVs in 1975 but had neon bulbs instead of LEDs
Many many much larger 7-segment displays using bulbs and lamps, but the point here is the LED's...
I am also guessing that these type of displays could have been used for the clock and timers on some podiums used by lecturers, board rooms, courtroom witness stands, and similar applications.
Those kinds of things were not used back then.
Awesome video, like always.. you rock!
You are doing the vintage electronics community such a beautiful service, this is why I will be a forever patron
Very Cool Fran !
T-1 in three quarters? What?? Is that what all we others call 5mm LEDs 😁
Fran could it be that these are the first industrial green LED'S?
Amazing color. Reminds me of vaseline glass.
You can make excellent light pipes from hot glue. I was thinking that you should do a video on the very earliest "Price Is Right" displays when the first items went up for bids and they used digits made from 35 (7x5) light bulbs each segment. For what ever reason they changed over to their own green and orange seven segment displays by 1974. They still used the light bulbs in other parts of the show, such as the showcases however. Thanks for being the "Queen of displays"!
Can remember horrible Nixie tube displays back in the 1960's. Forget what first digital displays that small hand held calculators used but think it was a 9 volt battery did not last more then 10 to 15 hours.( guys I was in high school with used the very small calculators to cheat on math test back around 1968 ).
Not "Sigma", probably Signetics.
I wonder if one could 3D print the light pipes and LED holders to make their own displays?
Surprised they didnt grind the LED top flat and short with no air gap to the light pipes. It would have been thinner too.
It looks like they had the 3mm and 5mm standard size then too.
That 6 is unusual in that it doesn't light up the top LED.
Not unusual at all - all of the 7400 7-segment drivers drop the heads and tails on 6 and 9.
I don't know why but I've always found green the least interesting LED colour. It's not that I don't like the colour green but with LEDs it's always this pale yellowish green colour that's not very pronounced. My oven and microwave both have a green LED panel and I've even thought about opening them up to change them for red LEDs 😂
I am the opposite, I always liked green and yellow 7-segment displays better than red ones. Except the red TIL 306 - 308 and especially 311, those are my favourites, but they are too tiny for a desktop LED clock.
@@mrnmrn1Oh but I like the yellow as well. It's just a matter of taste.
The year I was born.
What animal you mean😅 2:37
8:03 yes, very interesting. 😂😂📣📣📣
Bin a View Yippeee. Great video Fran. Thanks
As "monstrous" as these displays are, they're pretty much as small as you can make a display with standard 5mm LEDs.
i would like to eat that big LED in cake form.
this is a comment.