As an electronics experimenter I would have to say the REAL eternal chip is the 555 introduced in 1972. It's become a bit of a meme: You could have used a 555 for that!
It's become a bit of a meme: You could have used a 555 for that!
Unfortunately, those days seem to be gone. Now any time I see someone point out "you could just use a 555 for that", people are replying "I just threw an PIC/AVR/STM32/RPi in there instead...software is so much better than having to do math to calculate those R and C values".
MCUs are just too cheap not to use them these days.
They were always more flexible, are usually more accurate, and are often easier to engineer. With the price point now being roughly the same, it makes zero business sense to go for a 555.
"You could've used a 555" is becoming the new "you could've used a punch card"/"you could've used a vacuum tube": true, but would that make it better?
Just last week I had to open first time alarm clock with green 7-segment display. Because I accidentally dropped it while vacuuming and antenna cord broke as it was so firmly under picture frame holding nail. And while open cleaned interior from dust, used greasy PRF to lubricate pots, switches and tuning wheel. If I recall correctly it did have that LM8560 chip in int and with display looked almost exactly what was in subject article inside.
Label on bottom claims:
-----------------------------
Luxor CR 9016
NOKIA Consumer Electronics
International S.A
(FI)(N)(S)[x] 230V ~ 50Hz
Battery 9 V
MADE FOR NOKIA IN CHINA
-----------------------------
And another smaller sticker
SERIAL NO.
9302-00106
I bought -85 before christmas because my then girlfriend told that alarm clock that I've built myself using standalone clock module purchased from a local electronics component store was too ugly for us and had to go. Sure, I took
that old one to summer cottage and once I saw this better looking to make her happy. What couldn't a young man do to make is becoming fiancé happy, right.
Q: But why the device is branded Luxor and it's made for NOKIA?
A: Because NOKIA bought bit earlier that year (1985) Swedish Luxor consumer electronics. And I guess they did not had yet time redo chassis with NOKIA printed on and this was a still products transition period.
NOKIA was still at that time making also TV sets and was about to bring two years later its first completely new way of implementing analog TV using digital processing chips, which allowed quite nice fieatures like PIP which was great help making VHS recording without ads. I had one of those TV-sets (M-model) and used it about 10 years.
But that alarmclock radio from -85 is still going strong, good shape and it definitely was good purchase about 40 years ago.
e: Sorry about formatting, I tried to find how to format literally, but couldn't find. OK, good enough now.
Great passion for the subject, definitely doesn't get discouraged by their less than perfect command of English and didn't use an LLM to butcher the text's authentic character.
I find that in my own writing I no longer strive for perfect grammar and polish since nowadays it actually cheapens the end result, everybody has perfect grammar today.
Waaay off topic, but does anyone know why LLMs don't have poor grammar if they were trained on the average/poor grammar of the internet? Why don't they mix up then/than or it's/its, or use hypercorrections like "from you and I"?
(Update: of course I had to ask my friendly neighborhood LLM, and the answer is the correct usages still dominate incorrect ones, so statistics favor correctness. They down-weight low quality sources (comments like mine) and up-weight high quality ones (published books, reputable news sites). Then human reinforcement learning adds further polish.)
Two phenomena at play, correct spellings tend to be the most common on aggregate in a large enough dataset so there’s a bias, and the finetuning step (Instruct SFT) helps the model hone down on what it should use from the set of all possible formulations it saw in pretraining.
This is why LLMs can still channel typos or non/standard writing when you ask them to write in such a style for example.
This summer I've made indoor (no direct sunlight) solar powered kitchen timer and I used STM32L011, it's winter and it's still working and voltage is stable. The power consumption is 100-150uA (28uA for display, 80uA for mcu, the rest is 1.2-to-3V boost). But it's only on when I cook (maybe 1h a day).
I was excited to see the features of the chip that most clock manufacturers left undocumented described. There were a few I wasn't aware of and I'm going to try them on a vintage clock. I remember doing the hour/minute while holding alarm to reset the alarm to 0:00. I found that when I was a kid and thought it was so cool to discover a feature.
The article bringing up flip-flop clocks reminded me of another mechanical digital clock that I can not quite remember the name of. It was from roughly the same time period as the flip-flop alarm/radio clocks but the numbers were wire grids or cutouts in wire grids and as the numbers changed they sort of faded from one digit to the next. I can't quite remember how the mechanism worked and the only clock of this sort I have ever seen was the one I bought ~20 years ago just to take apart and see how it worked. Anyone know what I am talking about?
The mechanism was surprisingly simple once I got it opened and saw how it worked but from the outside made no sense, I probably stared at that clock for an hour trying to figure out how it worked before I finally opened it up to see what was inside. I might still have the clock mechanism in a box out in the garage.
Edit: I suspect these clocks were actually from the time period at the end of flip-flops, showed up too late to become common, LEDs/LCDs killed them. The digits were on the dim side, perfectly fine for a bedside alarm clock and quite good for that situation but you had to be fairly close to clock to read it in a well lit room. Better than a flip-flop in a dark room but worse than an LCD in the light.
Went out into the garage and dug it out, it is a Telechron Mechanical Occlusion Display, here are a couple videos. First does a good job of showing how it looks when time changes, second is a 12 hour stream for the diehard.
The brightness of the clock was about the same as a tired old VFD that has consumed most of its phosphor but this was something much simpler and something anyone could figure out how it worked once they saw the insides. The general look was closer to the nixie tubes the other commenter mentioned but these grids did not emit the light, the light source was a standard bayonet base bulb or two behind the mechanism. I think the smoked plastic on the front was also part of how it worked, it acted as a filter and without it you saw everything but the numbers you wanted to see.
Might have to go dig into that box in the garage and see if I still have it. I had intended on making a stand alone clock from it; the radio is not very good and the case has seen better days, so I was going to make a case for just the clock mechanism, perhaps its time.
There are projection-type digit displays. I can't seem to find a picture at the moment, but these had an array of incandescent bulbs which project the image of the digit onto an internal screen. The timeline seems about right, this was peak Apollo era tech.
There's also nixie and numitron tubes, as well as some neon digit displays. If it wasn't a tube, maybe it was a nixie-like display with a stack of acrylic plates each illuminated by an individual bulb.
A retro red LED clock actually adds to the calm atmosphere of my bedroom. I can’t really sleep without one now.
On the other hand, the only saving grace about my bright green and blue LED router is that someone whose hand should be shaken thought to allow software disabling or even a scheduled disabling of the LEDs.
Yes! I actually bought one recently after staying in a hotel room that had a (recent - clearly a design choice) alarm clock with a big, dim, red LED display.
One of the most interesting aspects it that it's all state machines and logic, with no CPU. This explains the weird glitches, e.g. having to not release one button while pressing another to avoid erroneous time setting. It shows what we take for granted that's trivial to do in software.
> Moving from Italy to Germany, I noticed that my clock radio with the LM8560 is considerably more accurate in Germany than Italy. Here, I never need to adjust it.
The interesting thing is that both countries are part of the Continental Europe Synchronous Area, so they are by definition running on the same frequency.
There must be a different explanation for the change in accuracy, but I wonder what?
In high school I had one of the mechanical "flip" clocks. Then later an LED clock which almost certainly used the LM8560 (a Sony, which lasted far longer than I expected. Back when products were built with quality in mind). And as the article says, the chip depends on the AC frequency (50/60 Hz) to keep accurate time. For the US market, that input was likely hardwired to 60 Hz via a jumper. Japan must have used a switch, given it's mixed 50/60 Hz national power standard.
These days I have an LCD clock that does not use the LM8560 but instead gets it's time from the Radio Data System values embedded in the FM broadcast. Possibly using the Sanyo LC72723 to decode them. The CT (clock Time & Date) data field is accurate to within 100ms according to wikipedia:
The part about the clock chip using the frequency of the AC power source as a clock source is pretty nifty, but then +-14 minutes/day of inaccuracy (+-2%) as the article mentions, is pretty off.
Then in the late 90's and early 00's you almost got alarm clock at "Dollar Stores" for $15,
and for really cheap pocket FM radios, you could get them as prizes with sodas and such,
as a marketing scheme, with the soda logo printed in the device.
With no internet, often you were in $REMOTE_FORGOTTEN_RURAL_VILLAGE and the TV antenna didn't have tons of nearly TV repeaters/relays, you would love some FM/AM radio
with cool stations reaching over 100 and 200 kms in case of AM ( I remember to listen heavy metal/gothic metal stations from Portugal in Spain within 100 kms from the border ). In Spain, either boring national and international pop radioformula, or soccer past dinner everywhere.
Oh, btw, one thing I hated from these clocks it's having to reset the time because it was misconfigured on a power cut. Nowadays they could just put some firmware and flash it for 0.0001 euros per device, if not less.
I remember how badly these radios would drift off-time when running on the battery backup! He explains in the article about how the back-up oscillator is a simple R-C circuit because the power line reference is absent.
It would also kill the backup battery in a couple of hours. If you're in an area with prolonged, frequent backups it wasn't worth installing the battery. It was only good for occasional, short blackouts of a few seconds or less.
On that note. I tried to make candle replacement out of yellow LEDs in the 1980-years. To read books in de tent. But no matter how many leds I added it just was not enough.
Being not a programmed micro controller, the LM8560 is also a virtually eternal component. Many modern micro controllers incorporate a flash memory to store the software that let the controller work and execute the desired functions. Flash memories retain their content not for an unlimited lifespan. It may be several decades, but before or later it comes the day when they begin to lose their content, and the micro controller stops to work. This can’t happen to LM8560, because it doesn’t contain any flash memory.
That's a strawman, as the cheapest devices using microcontrollers use mask ROM.
Mask ROM is actually starting to become less common as the price of OTP flash has dropped significantly, and changes can be implemented without paying for a new set of masks.
As an electronics experimenter I would have to say the REAL eternal chip is the 555 introduced in 1972. It's become a bit of a meme: You could have used a 555 for that!
https://en.wikipedia.org/wiki/555_timer_IC
It's become a bit of a meme: You could have used a 555 for that!
Unfortunately, those days seem to be gone. Now any time I see someone point out "you could just use a 555 for that", people are replying "I just threw an PIC/AVR/STM32/RPi in there instead...software is so much better than having to do math to calculate those R and C values".
MCUs are just too cheap not to use them these days.
They were always more flexible, are usually more accurate, and are often easier to engineer. With the price point now being roughly the same, it makes zero business sense to go for a 555.
"You could've used a 555" is becoming the new "you could've used a punch card"/"you could've used a vacuum tube": true, but would that make it better?
Yep. Just used a 555 today to whip up a low frequency clock source.
You can even make a rug out of it. https://www.righto.com/2025/09/marilou-schultz-navajo-555-we...
Or that opamp, the 741?
How about that 8 sound effects IC with the machine gun, bombs away, laser pew-pew, siren sounds?
76477. I still have one on a board around here somewhere.
https://en.wikipedia.org/wiki/Texas_Instruments_SN76477
I'm thinking of these ICs: https://www.reddit.com/r/AskElectronics/comments/a8af60/can_...
One of the more famous toys using it (in blob form) is the Executor/Echo Keyller keychain: https://youtu.be/20W6AJuMjEk
Related video: stop using the LM741 https://www.youtube.com/watch?v=e67WiJ6IPlQ
LM324 or LM358 is the way to go
AY-3-8910 or gtfo.
Highly agree
Hah, what a coincidence this post is.
Just last week I had to open first time alarm clock with green 7-segment display. Because I accidentally dropped it while vacuuming and antenna cord broke as it was so firmly under picture frame holding nail. And while open cleaned interior from dust, used greasy PRF to lubricate pots, switches and tuning wheel. If I recall correctly it did have that LM8560 chip in int and with display looked almost exactly what was in subject article inside.
Label on bottom claims: -----------------------------
And another smaller sticker I bought -85 before christmas because my then girlfriend told that alarm clock that I've built myself using standalone clock module purchased from a local electronics component store was too ugly for us and had to go. Sure, I took that old one to summer cottage and once I saw this better looking to make her happy. What couldn't a young man do to make is becoming fiancé happy, right.Q: But why the device is branded Luxor and it's made for NOKIA? A: Because NOKIA bought bit earlier that year (1985) Swedish Luxor consumer electronics. And I guess they did not had yet time redo chassis with NOKIA printed on and this was a still products transition period.
NOKIA was still at that time making also TV sets and was about to bring two years later its first completely new way of implementing analog TV using digital processing chips, which allowed quite nice fieatures like PIP which was great help making VHS recording without ads. I had one of those TV-sets (M-model) and used it about 10 years.
But that alarmclock radio from -85 is still going strong, good shape and it definitely was good purchase about 40 years ago.
e: Sorry about formatting, I tried to find how to format literally, but couldn't find. OK, good enough now.
Great passion for the subject, definitely doesn't get discouraged by their less than perfect command of English and didn't use an LLM to butcher the text's authentic character.
I find that in my own writing I no longer strive for perfect grammar and polish since nowadays it actually cheapens the end result, everybody has perfect grammar today.
Waaay off topic, but does anyone know why LLMs don't have poor grammar if they were trained on the average/poor grammar of the internet? Why don't they mix up then/than or it's/its, or use hypercorrections like "from you and I"?
(Update: of course I had to ask my friendly neighborhood LLM, and the answer is the correct usages still dominate incorrect ones, so statistics favor correctness. They down-weight low quality sources (comments like mine) and up-weight high quality ones (published books, reputable news sites). Then human reinforcement learning adds further polish.)
Two phenomena at play, correct spellings tend to be the most common on aggregate in a large enough dataset so there’s a bias, and the finetuning step (Instruct SFT) helps the model hone down on what it should use from the set of all possible formulations it saw in pretraining.
This is why LLMs can still channel typos or non/standard writing when you ask them to write in such a style for example.
I would also expect a grammar phase to be part of the training, with an RL pass where the output is fed to a grammar check engine.
This summer I've made indoor (no direct sunlight) solar powered kitchen timer and I used STM32L011, it's winter and it's still working and voltage is stable. The power consumption is 100-150uA (28uA for display, 80uA for mcu, the rest is 1.2-to-3V boost). But it's only on when I cook (maybe 1h a day).
https://imgur.com/a/ME1tx2c
Very cool. Though it's unfortunate that most DIY electronics projects end up looking like IEDs, mine included
Well, IEDs are certainly a type of DIY electronics project?
If they weren’t improvised, they’d be factory explosives devices (FEDs) after all?
Haha, the main meshtastic discord has a #notabomb channel for those sharing their DIY builds
I was excited to see the features of the chip that most clock manufacturers left undocumented described. There were a few I wasn't aware of and I'm going to try them on a vintage clock. I remember doing the hour/minute while holding alarm to reset the alarm to 0:00. I found that when I was a kid and thought it was so cool to discover a feature.
The article bringing up flip-flop clocks reminded me of another mechanical digital clock that I can not quite remember the name of. It was from roughly the same time period as the flip-flop alarm/radio clocks but the numbers were wire grids or cutouts in wire grids and as the numbers changed they sort of faded from one digit to the next. I can't quite remember how the mechanism worked and the only clock of this sort I have ever seen was the one I bought ~20 years ago just to take apart and see how it worked. Anyone know what I am talking about?
The mechanism was surprisingly simple once I got it opened and saw how it worked but from the outside made no sense, I probably stared at that clock for an hour trying to figure out how it worked before I finally opened it up to see what was inside. I might still have the clock mechanism in a box out in the garage.
Edit: I suspect these clocks were actually from the time period at the end of flip-flops, showed up too late to become common, LEDs/LCDs killed them. The digits were on the dim side, perfectly fine for a bedside alarm clock and quite good for that situation but you had to be fairly close to clock to read it in a well lit room. Better than a flip-flop in a dark room but worse than an LCD in the light.
Went out into the garage and dug it out, it is a Telechron Mechanical Occlusion Display, here are a couple videos. First does a good job of showing how it looks when time changes, second is a 12 hour stream for the diehard.
https://youtu.be/r9VA15DzX9k
https://youtu.be/NLuRMLqI6C8
Maybe Vacuum Fluorescent Displays?
as mentioned on https://www.youtube.com/watch?v=FH6LzV8FaEw and https://en.wikipedia.org/wiki/Vacuum_fluorescent_display
The brightness of the clock was about the same as a tired old VFD that has consumed most of its phosphor but this was something much simpler and something anyone could figure out how it worked once they saw the insides. The general look was closer to the nixie tubes the other commenter mentioned but these grids did not emit the light, the light source was a standard bayonet base bulb or two behind the mechanism. I think the smoked plastic on the front was also part of how it worked, it acted as a filter and without it you saw everything but the numbers you wanted to see.
Might have to go dig into that box in the garage and see if I still have it. I had intended on making a stand alone clock from it; the radio is not very good and the case has seen better days, so I was going to make a case for just the clock mechanism, perhaps its time.
There are projection-type digit displays. I can't seem to find a picture at the moment, but these had an array of incandescent bulbs which project the image of the digit onto an internal screen. The timeline seems about right, this was peak Apollo era tech.
There's also nixie and numitron tubes, as well as some neon digit displays. If it wasn't a tube, maybe it was a nixie-like display with a stack of acrylic plates each illuminated by an individual bulb.
Nixie tubes worked as you describe but with the glowing elements inside a gas-filled glass bulb
A retro red LED clock actually adds to the calm atmosphere of my bedroom. I can’t really sleep without one now.
On the other hand, the only saving grace about my bright green and blue LED router is that someone whose hand should be shaken thought to allow software disabling or even a scheduled disabling of the LEDs.
Yes! I actually bought one recently after staying in a hotel room that had a (recent - clearly a design choice) alarm clock with a big, dim, red LED display.
One of the most interesting aspects it that it's all state machines and logic, with no CPU. This explains the weird glitches, e.g. having to not release one button while pressing another to avoid erroneous time setting. It shows what we take for granted that's trivial to do in software.
> Moving from Italy to Germany, I noticed that my clock radio with the LM8560 is considerably more accurate in Germany than Italy. Here, I never need to adjust it.
The interesting thing is that both countries are part of the Continental Europe Synchronous Area, so they are by definition running on the same frequency.
There must be a different explanation for the change in accuracy, but I wonder what?
In high school I had one of the mechanical "flip" clocks. Then later an LED clock which almost certainly used the LM8560 (a Sony, which lasted far longer than I expected. Back when products were built with quality in mind). And as the article says, the chip depends on the AC frequency (50/60 Hz) to keep accurate time. For the US market, that input was likely hardwired to 60 Hz via a jumper. Japan must have used a switch, given it's mixed 50/60 Hz national power standard.
These days I have an LCD clock that does not use the LM8560 but instead gets it's time from the Radio Data System values embedded in the FM broadcast. Possibly using the Sanyo LC72723 to decode them. The CT (clock Time & Date) data field is accurate to within 100ms according to wikipedia:
https://en.wikipedia.org/wiki/Radio_Data_System
The part about the clock chip using the frequency of the AC power source as a clock source is pretty nifty, but then +-14 minutes/day of inaccuracy (+-2%) as the article mentions, is pretty off.
Then in the late 90's and early 00's you almost got alarm clock at "Dollar Stores" for $15, and for really cheap pocket FM radios, you could get them as prizes with sodas and such, as a marketing scheme, with the soda logo printed in the device.
With no internet, often you were in $REMOTE_FORGOTTEN_RURAL_VILLAGE and the TV antenna didn't have tons of nearly TV repeaters/relays, you would love some FM/AM radio with cool stations reaching over 100 and 200 kms in case of AM ( I remember to listen heavy metal/gothic metal stations from Portugal in Spain within 100 kms from the border ). In Spain, either boring national and international pop radioformula, or soccer past dinner everywhere.
Oh, btw, one thing I hated from these clocks it's having to reset the time because it was misconfigured on a power cut. Nowadays they could just put some firmware and flash it for 0.0001 euros per device, if not less.
I think some more advanced ones ran an internal “UPS” on 9V.
Effectively a relay that would be held by mains and fail to 9V if the power went out with some replacement 60hz signal.
As I recall, it would run the sound alarm but not the display.
I remember how badly these radios would drift off-time when running on the battery backup! He explains in the article about how the back-up oscillator is a simple R-C circuit because the power line reference is absent.
It would also kill the backup battery in a couple of hours. If you're in an area with prolonged, frequent backups it wasn't worth installing the battery. It was only good for occasional, short blackouts of a few seconds or less.
Probably didn't help that your 1980s and 1990s 9V battery was likely a zinc-carbon battery, about 1/2 - 1/5th the mA of alkaline.
I do remember that I could unplug and replug my alarm clock pretty quickly and it wouldn't lose its time if I needed to move sockets. Yay capacitors?
On that note. I tried to make candle replacement out of yellow LEDs in the 1980-years. To read books in de tent. But no matter how many leds I added it just was not enough.
Mask ROM is actually starting to become less common as the price of OTP flash has dropped significantly, and changes can be implemented without paying for a new set of masks.
> “Digital” doesn’t mean necessarily “electronic”. It means that the time is show actively by digits and not by hands.
Kind of weird since digitus means finger.