5:55 video released on May 5th, as per description :)
For something feeling like a fairly specific IC, I remember seeing many projects that use it throughout the years in wacky ways - and seeing it makes me happy to know that the sentiment for this little piece is shared.
I learned (long ago) it’s trivial to fool my satellite receiver’s modem’s dial tone verification for remote pay per view ordering (it doesn’t phone home right away but gets angry if it’s not connected to a phone line).
Turns one a single frequency that’s remotely close to one of the two tones of a dial tone will convince it. Wasn’t sine wave either but not a problem! 555 powered by a 9V battery.
otoh i.m surprised the accelerometer was already available since 1927. since microcontrollers only the hardcore eecs kids build pid controllers from opamps for fun (only do hn on phone hard to link to that maker article of a fully analog segway where the writer missed the "analog" part and was like WOW a self balancing 2 wheeler by a grad student and not another baby's first Arduino bday kit
I remember reading somewhere that it's the highest-selling IC of all time, which is a little surprising! I'd have guessed the winner would be an op-amp of some kind.
555s are such delightful little guys. I used a pair of them, plus an ebay telephone line driver, to make an old telephone ring: https://hardfault.life/p/telco-2
One timer runs at the ~20Hz ring frequency, and the other runs at ~0.2Hz on a 20% duty cycle. The slow one's output feeds the enable line of the fast one, so you get 1-second burts of ringing, then a few seconds of silence, then ringing... just like a normal phone.
I moved about 5 months ago and haven't had time to get back to this project. The goal is to build a little phone company in a box, so I can have all my old PCs talk to each other with their modems.
I still have the Forrest Mims III Radio Shack "555 Engineer's Mini-Notebook" somewhere in my basement. And rumor has it that Sammy Hagar can't drive 555 because his car just isn't fast enough!
Can't watch it right now, but upvoted for Dave Jones. He's taught me so much. Absolute treasure, and the host of one of the last great active forums. Thank you for not blackholing all that info on the disaster that is Discord, like so many other communities.
Back when radio shack still existed I would buy a 555 timer during every visit. I live collecting them and still have a bunch somewhere stored. I continue to do it with the 328p arduino boards as well whenever I visit my local microcenter.
As a kid I didn’t understand what the 555 timer chip on the Apple II disk controller was doing but I learned the hard way that when you misalign the pins on the drive connector cable and the 555 chip releases its blue smoke you can’t use the drive anymore :(
When I was a camp counselor in my 20s I designed a one-octave "piano" out of one of these, a battery, paperclips for keys, and a shitload of resistors. We had the kids build them on proto board. They sounded harsh but you could play Mary Had a Little Lamb on them!
I used one of these to win an inter-school science competition when I was ~13. It was a minute timer. The competition board doubted I had built it all myself, so they plonked it down in front of me and demanded I draw the circuit diagram in front of them.
The 555 timer is still the most popular chip that hobbyists add to their parts inventory (see rankings at https://partsbox.com/ecdb.html). I find this both interesting and curious — I'd say it has mostly nostalgic value at this point. Almost every practical problem today is better solved by something else. And yet it persists, I guess mostly because of beginner tutorials and first LED blinky circuits.
One nice thing about the 555 is that at least it aged well and still is very usable in those beginner tutorials. Unlike for example the uA741 which no one should use.
Fun fact: his original concept needed 9 pins and therefore was going be forced to have a 14 pin package. A late epiphany got it down to the 8 pin version we know today.
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[ 2.8 ms ] story [ 66.4 ms ] threadFor something feeling like a fairly specific IC, I remember seeing many projects that use it throughout the years in wacky ways - and seeing it makes me happy to know that the sentiment for this little piece is shared.
Turns one a single frequency that’s remotely close to one of the two tones of a dial tone will convince it. Wasn’t sine wave either but not a problem! 555 powered by a 9V battery.
i have the page archived, but it's called A New Solar _ Wind Charge Controller Based on the 555 Chip (2_7_2026 12
I can upload the webrip if anyone wants it
555s are such delightful little guys. I used a pair of them, plus an ebay telephone line driver, to make an old telephone ring: https://hardfault.life/p/telco-2
One timer runs at the ~20Hz ring frequency, and the other runs at ~0.2Hz on a 20% duty cycle. The slow one's output feeds the enable line of the fast one, so you get 1-second burts of ringing, then a few seconds of silence, then ringing... just like a normal phone.
I moved about 5 months ago and haven't had time to get back to this project. The goal is to build a little phone company in a box, so I can have all my old PCs talk to each other with their modems.
Maybe it could work if you used 5 timers?
https://displate.com/displate/2002057
One nice thing about the 555 is that at least it aged well and still is very usable in those beginner tutorials. Unlike for example the uA741 which no one should use.
https://shop.evilmadscientist.com/productsmenu/tinykitlist/6...
Very cool. (Looks like it uses 26 transistors. I assume the die is similar.)
Fun fact: his original concept needed 9 pins and therefore was going be forced to have a 14 pin package. A late epiphany got it down to the 8 pin version we know today.