555 Timer All Modes

[@HazeAnderson]

"Anyway, like I was sayin', 555 is the fruit of the sea. You can barbecue it, boil it, broil it, bake it, saute it. There's uh, kabobs-stable, creole-stable, gumbo-stable. Pan fried-stable, deep fried-stable, stir-fried-stable. There's pineapple shrimp-stable, lemon shrimp-stable, coconut shrimp-stable, pepper shrimp-stable, soup-stable, stew-stable, salad-stable, and potatoes-stable, burger-stable, sandwich. That- that's about it."

[@learnelectronics]

Thank you Forrest lol

[@pascalfortin2696]

Didn't think I'd laugh coming here this morning. Thank you

[@jlucasound]

@@learnelectronics It was Bubba done said that! :-) Forrest: "My Momma said, Life is like a box of 555's. You never know what you might make." ;-)

[@seaham3d695]

Stable diet? :)

[@jimmyneutron8702]

Can i get an uhhhhhhhh mustard microwave stable

[@davidprice2861]

Yes the 555 is a gem, so versatile and tolerant 5-15V. suits so many applications, can supply up to 20 mA by itself to a load. Very robust and stable. Did my first electronic experiments with them. Love em.

[@michaelpadovani9566]

This is a beautiful summary of the 555. Love the blue background mat. Also appreciate you going through some of the datasheet.

[@disectormusic]

well, i tried the 555 used as a VCO in a synthesizer (something ive been building) , i absolutely fell in love with the amount of things it could acoustically do. the sounds are extremely unique and ive never heard such big a roar from such a tiny component.

[@untrust2033]

Can you give an example I'm having trouble finding synth schematics for it D:

[@fifaham]

It roars but and I hope it wont bite ! LOL

[@peterashley6042]

I love 555 videos. Yours are always great. Thank you.

[@realityisanalog]

Thanks for putting this together. Clear and concise.

[@kali_muon]

This is a great 555 timer overview. I'll definitely show it to my friends who are studying EE. A cool use of the 555's monostable mode is bounce removal; my EE professor told me about that yesterday. As you said, it's the chip that does everything.

[@midnightrizer]

there are easier and cheaper way to debounce though.

[@robbyprust]

You should make a 555 timer using discrete components, it would give a big understanding of just how amazing the chip was when it came out .

[@robertcalkjr.8325]

There is one already available. See the link in my other comment.

[@kootaru_]

@@robertcalkjr.8325 I can't find it((((((((((

[@robertcalkjr.8325]

@@kootaru_ Here you go: shop.evilmadscientist.com/productsmenu/652

[@Inquire98]

@@robertcalkjr.8325 'Thank GOD'🙏🏾 and thank you very much ☺️ Also Happy New Year 🌅I am a student of electronics, information technology and mathematics 😁 I am doing research on the 555 timer ⏳ for my own publication 🙄 I'd like to know 🙄 if you have any suggestions 🤔

[@robertcalkjr.8325]

@@Inquire98 Merry Christmas and Happy New Year. I haven't researched it much and I have been away from electronics repair for a while. But the 555 can be controlled using resistance through the #4 Reset Pin. That will give you something to investigate. Have fun!

[@robertsmiczsmiczamplificat593]

Nicely done. A great video for new electronics enthusiasts. Don’t forget the single button latch. Push on, push off.

[@mikeoliver3254]

Great video Paul. I really like the idea showing all three of the major configurations at once. It is one of the ways I have been practicing my circuit analysis. I’m actually working on a 555 based stepper motor controller right now. I know i could do it more easily with an Arduino but overcoming the challenges are a big part of the fun.

[@learnelectronics]

Sure you could do it with an Arduino, but then you wouldnt know what's going on under the hood so to speak. Like Feynman said, "What I cannot create, I do not understand."

[@mikeoliver3254]

Exactly.

[@RicardoPenders]

Another very useful chip is the Darlington array ULN2003 which can be used for motor control but I'm actually using 2 of them as an interface for my Raspberry Pi so that I can connect my GPIO pins directly to the interface without having to worry about any series resistors or blowing up my GPIO ports or worse and be able to switch up to about 50 volt with a 3.3 volt GPIO signal... I'm using the interface to control 4 channels of 12 volt RGB LED strips with only 3 GPIO pins in use, normally you need 3 GPIO pins for 1 RGB LED strip, another great thing using the ULN2003 IC is that because it can only sink current the signal is inverted so when the signal is high the output will go low or sink the current to ground and with those 12 volt LED strips that's exactly what needs to be done and you can do the same thing if you want to control a brushless dc motor with a PWM signal coming from a microcontroller such as the Arduino or Raspberry Pi. I hope this is helpful information regarding your project. Best regards, Ricardo Penders

[@gitarmac]

@@learnelectronics I started out doing a few minor electrical repairs in my home after I retired. That peaked my current about electricity in general and electronics. So I got an Arduino kit. I messed with it a little, it was fun, but I wasn't learning how the individual components worked. So now I've been making breadboard circuits to attempt to learn more about electrical components. I've been having so much fun and it's been fascinating, I may or may not go back to messing with the Arduino, I'm pretty sure I will at some point but learning about individual components and how they work together is satisfying in itself. Previously my only exposure to this kind of thing was when I took physics in college which believe it or not made learning this more confusing in some ways. So I'm enjoying this channel a lot, I wish there was a little more discussion on component substitution, my little kit doesn't have everything, but I've ordered a larger capacitor and resistor selection so that should help.

[@theweekendrecordist9040]

Thanks for all this videos, i am currently learning about 555! Now I understand a little more about the different modes!

[@peterlethbridge7859]

This is rapidly becoming my favorite channel for learning electronics. Thank you so much for putting an amazing series of videos together

[@jerryp1012]

Always enjoy the 555 timer videos

[@johnruscigno5738]

Great tutorial video sir. These comments are over a year old though, how did I not find your videos sooner? Would've saved myself a lot of time.

[@Wes8761]

Hey man. I am so sorry to hear about your medical condition. Please keep sharing your knowledge

[@satchell78]

Legit, I bumped it up to 7 V and what a world of difference! Thanks, hope all is well.

[@chrisdavid1410]

These videos are always a great joy to watch, and I always learn something new.

[@georgechambers3197]

I like the Forrest Mims book 555 Timer IC Circuits. Tons of simple projects in it with the 555 and 556 timers. Sad to see the last 555 videos but all good things must end.n Thanks for a great 555 series, I'm sure I'll watch some over again!

[@learnelectronics]

If you or anyone has specific questions I'll be happy to dig into them. But I think I covered the generalities pretty well.

[@georgechambers3197]

That you did. The book just has a lot of projects to help reinforce what you've taught us. 😀

[@kapishss5540]

I just wanna say... his hands are radiating the beauty of a man who works hard or someone who has experienced hard labor

[@saysphilippe]

Great 555 video. Great as always!

[@jeffreyslominsky1275]

Thank you for sharing this, your lesson was great!

[@icedclips725]

nice video. been trying to teach myself this stuff out of boredom and finnally understanding 555 timer thanks

[@randybryson5519]

Great video! I worked for Signetics for 15yrs. That was one of the most popular ICs we had. Thx

[@kurusb7792]

Interesting

[@josedominguez2021]

Superb!!! Im here again...

[@moncarlovasquez564]

God Bless You! May the Lord Jesus healed your Congestive Heart Failure.

[@MasterBakerVideos]

I wonder how accurate the charts are. I've been using a general purpose 555, NOT a low voltage version, with voltage as low as 2.5 volts, although I typically use 3-4.2 volts, max. They still work fine, although with reduced amperage. When they say min. 4 or 5 volts minimum, depending on where you read it, doesn't jive with my experiments and projects.

[@johnf3326]

Well bugger Bob! I will give him a piece of my mind! 🤣🤣🤣

[@jeffsaxton716]

I have made an astable with an 18,000 MF cap. I'm waiting an hour or two for it to switch states.... The cap is charging. Very slowly, of course. My oscilloscope is useless, but my 1962 Gould paper chart recorder is tracking things well.

[@RicardoPenders]

I had to buy a bunch of the 555 chips because I can't find any of these chips on any modern hardware that I take apart for recycling, so Banggood it is... And I have been playing around with these chips, made all the circuits that you showed in this video, played with different capacitors, resistors etc. to see what happens. Now that I know more about it I have to say it is indeed a very interesting and versatile chip, I think it's rather cool. I made one more circuit using two 555 timer chips to make a police light, first it flashes the red LED's a couple times and then it flashes the blue LED's, back and forth but what's so special is that it doesn't flash each side one time but more like 3 to 5 times before going to the other chip to flash the other side 3 to 5 times... It works and looks really cool but I have no clue how it works, if it just did one flash each side it would make sense but how does it flash multiple times on each side is a mystery to me, maybe you can explain the phenomenon in a video?

[@cosmos8366]

There is a way of calculating the frequency of an astable circuit using a chart called a nomograph and cannot find any explanation of how to do this and would love to see a video with a step by step explanation of how to use this chart.

[@kiacatalla]

hello! can you kindly tell me the value of each components used in this breadboard? thank you!

[@gitarmac]

It looks like a couple of your circuits here are much simpler than the way they were presented in the videos dedicated to each specific mode. I'm having particular trouble trying to set up the 555 in monostable mode for some reason. My resistor and capacitor supply is limited, or maybe I'm missing a small mistake I'm making. But I'm not giving up!

[@josedominguez2021]

One year ago: Nice vdo again... Fantastic...!!!!

[@josedominguez2021]

Fantastic vdo. Thanks a lot!!!!

[@mohammedabrarahmed3299]

Great video with great explanation. It would have been great if you would have zoomed in on the breadboard while explaining the three modes. Thanks

[@frankhobsonKJ4CDM]

Watching old SciFi movies/shows and watch the 555’s flash. See a flashing light and be like I bet that is a 555. 😂

[@granumuse7847]

Thank you! Great work!

[@RicardoPenders]

I hear all the time that the 555 timer ic is very common and can be found everywhere, however after salvaging and recycling electrical components for several years now I never found the chip being used in any of the devices that I've had in my hands. I don't know what to think about it but I am a bit disappointed because of it and I do find it a bit strange, right? I've salvaged lots of power supplies mainly for computers and servers but also tv power boards for modern flat tv's but what I love to get my hands on is old crt tv's since those contain the bulky through hole components which are easily salvaged and are great for diy projects or usage on the breadboard and not to forget that it holds a beefy high voltage transistor, the flyback transformer plus all the nice enameled copper wire from the yoke and the demagnetisation coil that can be reused for making Tesla Coils or making your own AC flyback from it... That's what I did with it mostly and of course I learned a lot in the process of making my own flyback transformers, Tesla Coils and the driver circuits. The latest Royer Oscillator I've made I used the high voltage BJTs from 2 old crt tv's and the flyback transformer and the output is pretty impressive, it does behave very different compared to the ZVS driver although it's almost the exact same circuit the BJT based Royer Oscillator produces a lot more ion wind and starts to react with the electrodes further apart. The ZVS driver is of course much more efficient and my latest ZVS driver has an output of about 150 kilovolt when I connect it to my biggest flyback transformer which is absolutely crazy and very dangerous because of the high voltage and high amperage, I always tell my friends to get away from it and keep enough distance when I'm playing with it and to NEVER EVER touch anything when it's live or shortly after until everything is discharged. I still want to build a 555 timer based driver for my flybacks and Tesla Coils but I know that the inevitable will happen which is blowing up the chip, at least a couple of them I don't want to buy a bunch of the 555 timer chips, I rather pull them off some old pcb... Sadly I never find such a chip on the boards that people have donated to me. So can you tell me what pcb to look out for where I can find those 555 timer chips on, because I never found one before Best regards, Ricardo Penders

[@learnelectronics]

There's one in my Zeny switch mode power supply, there's an smd version in one of my USB phone chargers....

[@michaelmanspeaker7430]

Sort of relaxing. keep em coming

[@fullpushmetals6711]

Like #675! BaaM! Thanks monostable is what i need for my build! Times 110 builds of this... lmao Keep Pushin!

[@chetan26726]

Circuit diagram?

[@deepakns6931]

Well explained Paul I have always wanted this video

[@eladioh3858]

Hi Paul always love your videos. But I got the Hantek scope because of you and love it. Do you still have yours or sold it ? Do you still like it ? Thanks for your hard work 👍

[@learnelectronics]

I still have it. It's a great scope. I did however sell the Siglent.

[@shantanumajumdereeprojects6218]

What resistor and capactior values are you using for the monostable mode.

[@OregonDARRYL]

I want to make a one-shot circuit for a laser target gun. Is there a chart to determine what resistors and capacitor I would need for say... an on time of 100 milliseconds and off for 300 milliseconds? Thanks guys.

[@learnelectronics]

www.digikey.com/en/resources/conversion-calculators/conversion-calculator-time-constant

[@michaelszczys8316]

I need a low power circuit to turn a thing on for about a second, then off and repeat after about 10 seconds. Could I feed one 555 with another on monostable mode? Need a timer more off than on. Plus I could use two of these circuits alternating each other. Can it be done with 555s?

[@educationaltechnology8363]

you solved some of mysteries! subbed you are the MAAAAAAN

[@الأمينالحاج-غ2ف]

I like to make three light LEDs as monostable Green led 16 mints after it yellow LED 8 mints and Then 32 mints red LED. As indicating gave three lights lighting as times in mints.

[@RomuloFPBarretto]

I hope, and I pray for better conditions for you. I believe the most important day in our lives will be our last day. So make good things today for remembering that in your more significant challenger day.

[@wishicouldarduino8880]

I could ask a million questions about 555 556 and about 25 other ic chips it's because I got this awesome kit that is loaded with diagrams showing the pin outs for each one..😁👍

[@christiannielsen3863]

You actually haven't done a video about the 555 in bistable mode? I tried this one but mine doesn't stay on when I ground trigger pin? I mean it does some times... but far from all the time. I've tried a new 555 with the same result.

[@MalagasOnFire]

Timer neat chip that time pass and stills rocks. works with almost dead 9V batteries :P but not too below. Imagine two of this timers in a single chip :P the ... 556

[@gerrymcerlean8432]

Great videos. Thank you. Maybe I'm missing something, but I don't see the point of 'bi-stable' mode. Surely you could turn an LED on and off with a switch, a resistor and an LED. No 555 required and only one switch.

[@whisk3rs777]

He's using momentary switches yet they are behaving like they aren't. Which is what the 555 makes possible. 👍

[@الأمينالحاج-غ2ف]

Thanks

[@fifaham]

Nice one thank you.

[@juliafernandezfigueras6914]

Really nice video. I am trying to buil an electric muscle stimulator and I have seen a lot of circuit schematics and they use this kind of timers. Can you please do something abiut electric muscle stimulator with arduino?

[@learnelectronics]

That's not really my field, I'm sorry.

[@kevfrets]

Awesome! Is a breadboard schematic available for this demonstration?

[@learnelectronics]

No, sorry. I used schematics from the data sheeta. www.google.com/url?sa=t&source=web&rct=j&url=www.ti.com/lit/ds/symlink/ne555.pdf&ved=2ahUKEwjQ57XU5KLhAhVECKwKHcO6DncQFjAAegQIAhAB&usg=AOvVaw32jIkyVrYMHisUn5w1uhEq

[@injoelsgarage3934]

How do you use a 555 to pulse a counter? Thanks Joel

[@learnelectronics]

I would use it in astable mode. Figure out the frequency you need and choose the two resistors and one capacitor to make that frequency. The frequency is equal to 1.44 divided by (r1 +2r2)C

[@injoelsgarage3934]

@@learnelectronics thank you.

[@adamt7367]

Damn thank you man I understand these now!

[@Inquire98]

Happy New Year 🌅 I am doing research on the IC 555 timer ⏳ for publication 🌎 Can/will you suggest at least 3 pieces of reading material for my project 😉 I am going to re-review the material on your channel and website 🌎 Let me know 🙄 I look forward to hearing from you 😎

[@learnelectronics]

The Art of Electronics www.google.com/url?sa=t&source=web&rct=j&url=www.n5dux.com/ham/files/pdf/Forrest%2520Mims%2520-%2520555%2520Timer%2520IC%2520Circuits.pdf&ved=2ahUKEwjEm-_i4eztAhVhu1kKHR9QBbYQFjAAegQIARAB&usg=AOvVaw2Qu6UbVTrF_FHCwU2lDngq 555 Timer Data Sheet

[@luie.no1noob]

Bro in astable mode I want to keep the led on for 2-3 sec then off for min 8(or more min 8) sec for this plz tell me the value of resistor and capacitor

[@BryanDenham]

could this 555 chip be used to make a guitar delay pedal somehow? im new to making guitar pedals, (electronics in general )and have a lot to learn , so far i have been really enjoying your videos. thank you for the help.

[@planktonfun1]

I really need to buy those 555 timer, I keep running out of components just to make one mode

[@JR-tv4tn]

How about a 10 minute timer with flashing led and reset

[@robertcromwell9736]

How about the unstable mode?

[@learnelectronics]

Three modes: mono, bi, and a. Nothing else official listed in the data sheet.

[@johnf3326]

"Tee Hee" quoth he!

[@robertcromwell9736]

@@learnelectronics I think you created the unstable mode when you pulled that capacitor out?

[@javierperez_21]

@@learnelectronics you forgot the mode I invented, the f*cked up mode. It is when you mix up the pins and it gets hot... literally.

[@roygalaasen]

Robert Cromwell unstable? You mean unstable as something else than astable? Like random duty cycle?

[@Golobtin]

Hi Paul, I know almost nothing about electronic, yet somehow found your demo fascinating. I don't meant to impose, but was wondering if you could set me in right direction. Your wisdom in this is much appreciated. I refrain from reinventing the wheel. I need the most elegant way of doing this. I wish to come up with a timer circuit which interacts with a thermostat, one main heating element, one keep warm element and a buzzer when cooking is done. I have been reading on Arduino approach to this, but today I thought perhaps 555 can be used to achieve the same end in much smaller size. Here is the requirement: 1- Timer must cover 60 min. time, 2- A Dial is used to set the time (this will produce rice with bottom crust at desired crispiness), 3- A Display shows what Dial is set at, and the remaining timer when count down takes place. 4- When a button is pushed and pot-thermostat is closed (cold pot), the main 700W-Element is turned ON and cooking starts. 5- When pot-thermostat opens (water boiling point), 700W-Element is turned OFF and Timer STARTS/CONTINUES counting down. 6- When pot cools down enough to cause pot-thermostat to close again, 700W-Element is turned ON again and Timer PAUSES the count down. 7- This thermostat Close/Open, Element ON/OFF, and Timer Count Down/Pause/Continue repeats until Timer zeros. At this time a- 700W-Element --> OFF b- a 25W-Element --> ON (keep-warm) c- a Buzzer goes off Can this be done utilizing good old 555 and basic components, without the need for a micro-controller? Do you approve if this? If so, any idea what the circus looks like? As general / detailed explanation as you wish. Cheers Mohammad

[@coditize]

fantastic video

[@christiannielsen3863]

AARG why isn't your threshold connected to ground? mine has to be connected to ground to latch.

[@farabielec]

555 is old IC and has so many applications and usful.

[@danieldeon1492]

perfect video ! thank's

[@johnf3326]

What would be the maximum frequency you can get in astable mode? I think this little chip will be useful in designing and building a plasma multi spark ignition system for my classic honda motorbikes

[@learnelectronics]

Stable frequency? Nice square pulses? 300-500KHz depending on the chip. I've pushed a 555 to over 3MHz but it ain't pretty.

[@annaoaulinovna]

i think 555 made by aliens. but its waveforms are human made!

[@houaritifest1501]

So good, thanks

[@omarramirez5764]

I love that chip! Hope your health guet better.

[@raym9691]

Was wondering about a 555 push on push off circuit for an atx psu?single switch like on a computer.... Great video Paul!

[@learnelectronics]

An S/R latch would be what you are looking for in that application.

[@raym9691]

@@learnelectronics thank you very much Paul and I use your Amazon like to buy stuff when I can to help support the channel! Keep up the great work you are doing for everyone

[@kevinbeckenham3872]

Not bad for 58 year old timer chip 555 timer, mainly found as delay timer inside bathroom fan

[@tzurgolan8073]

hello learnelectronics If the button In the right circuit will remains pressed, the circuit will enter to loop or it will turn on and off only one time???

[@learnelectronics]

Don't know, never tried it.

[@tzurgolan8073]

thanks

[@kroome8]

great!!! nice video...

[@mayachm3473]

How to make the astable last longer

[@przemos7816]

Is it possible to turn the led for 1s and turn it off for 5s in a loop ( astable mode)?

[@takix2007]

Yes. Use the astable mode, replace the resistor that is connected to the capacitor with 2 branches in parallel: Branch 1: a resistor R1 and a diode; Branch 2: another resistor R2 and a diode in the reverse polarity. Choise R1 and R2 to match the desired on/off time.

[@przemos7816]

@@takix2007 I will try that tomorrow. Thank You!

[@johnf3326]

Great as usual! Greetings from Leeds, Yorkshire, UK! I have a question: I am designing my own capacitor discharge ignition system for a classic 1970 Honda. I think the 555 in monostable can give me a 3ms pulse output when the breaker points open (with a few simple mods). BUT the trigger voltage will last longer than 3ms (its like holding down the trigger button on your board). So can I get that short pulse no matter how long the trigger signal is applied? Then reset after the trigger signal is removed. My intention is to use mosfet to fire off a charged capacitor (200-300v from cheap chinese ebay booster circuit) across the ignition coil primary every time the breaker points open (for 3ms) then after that the capacitor is charged again as mosfet goes open circuit. Another mosfet will briefly cut the hv supply as the capacitor shorts across the (0.4 ohm) coil primary to avoid damaging the booster circuit. Many thanks. John

[@learnelectronics]

Yes. The 555 starts on the rising edge. So your timing will start when you upon receipt of the trigger.

[@johnf3326]

@@learnelectronics Hey thanks for the quick reply! Thats great info. I shall incorporate that into my circuit

[@dannbrauckmann1545]

Is there a way to make one color blink say 6-8 times, before switching to the other color? I'm trying to figure out how to switch between one flashing red and one flashing green LED. Basically, THIS. It begins at one minute and 20 seconds or so into the video. kzbin.info/www/bejne/lZLchWN7j9yVodU It looks to me like Mark Hamill is controlling it, like, he interrupts the green LED by bridging a connection or touching a switch with his little tool. How can this be done? I'm trying to fit it into a box roughly 47mm x 17mm x 10mm, along with two LR44 cells.

[@learnelectronics]

Multiple 555 timers cascaded

[@dannbrauckmann1545]

@@learnelectronics I'd love to see a video demonstration! I've got a project thread about this on All About Circuits, if you care to check it out, I'd REALLY appreciate it! forum.allaboutcircuits.com/threads/need-help-with-a-slightlr-different-led-flasher-circuit-novice-here.164708/

[@phrankus2009]

APPLICATION: Railroad Crossing Signal (Hyuk-hyuk)

[@TheResidentSkeptic]

What is supposed to happen in astable mode when you don't connect pin 4? My 555s seems to run fine with pin 4 unconnected. Will it just make it unstable over time?

[@learnelectronics]

Well its put that pin into an unknown state. Most of the time nothing bad will happen. But there is the possibility that it could go low and reset the chip. It won't damage anything if that's what your asking.

[@TheResidentSkeptic]

Just trying to understand how it works by messing with it. Electronics are usually pretty precise things, so it feels a bit odd that pin 4 only sort-of needs to be high.

[@learnelectronics]

That's because its active low. If it were active high and you didn't hold it low, the chip would reset whenever there was something it could capacitavly couple to...like your body

[@robertcalkjr.8325]

Thanks Paul! Yep, it is an amazing little IC! Here is a cool little 555 kit that some may be interested in building and playing with: shop.evilmadscientist.com/productsmenu/652

[@learnelectronics]

Oh that is too cool, I definitely want one!

[@robertcalkjr.8325]

Yeah, it is pretty cool! I have been aiming to get one but I keep getting distracted and forget about it. And then when I remember it, I don't have the money!

[@Inquire98]

@@robertcalkjr.8325 I am budgeting for 1 in February 2021

[@richardkieran6873]

I have a 555 question. I am trying to build a monostable circuit to replace the electronic shutter board in a camera. I have a working circuit with one hitch. When I press the momentary contact switch, the LED representing the shutter on the camera lights, times out, and goes off. Good so far. If I hold the switch down for a second, I still get my 2 second timing. BUT, if I hold the switch down longer than 2 seconds, the light stays on until I release the switch. OK for 2 seconds, I can be fast enough on the trigger to beat that. But it's not good for 1/250, 1/500, 1/1000 second. This behavior seems wrong to me. Is it normal? If so, it seriously limits the usefulness of this device. My circuit follows the monostable diagram in section 4.1 of the data sheet, with the Reset tied high and a 1k resistor between pin 2 (trigger) and Vcc. The switch grounds the Trigger pin when pressed. Am I doing something wrong? If this is normal behavior for this circuit, is there something I can add or change to get what I need? Thanks. AND thanks for the videos. They're great.

[@learnelectronics]

That's not right. Can you email me a schematic of your circuit?

[@richardkieran6873]

@@learnelectronics Sent to the email address on your About page.

[@richardkieran6873]

Found the answer! It's called edge triggering. A capacitor (0.01uf or 0.1uf) is used to connect trigger (pin 2) to the grounding switch, instead of a wire. A 10k resistor is connected to the trigger pin side of the capacitor to hold it high. The trigger sees only changes in voltage (AC). DC such as that from holding the switch down is blocked by the capacitor. It appears that without this modification, the behavior I originally described is normal. Might make a good video. Anyone trying to time a short interval with a manual switch is gonna need it.

[@richardkieran6873]

To clarify, the resistor from the trigger pin goes to Vcc.

[@josedominguez2021]

SUPER!! SUPER!! SUPER!!

[@sugonmadyik6222]

im always remember the IC names because 555 in thailand means "hahaha" LMAO

[@Muhammad_Sausage]

Why would you use the chip for the bistable mode? It’s just on / off ? 😂

[@phrankus2009]

GTK ! .. "Good Pookey" ... Thankyou.

[@anas2004]

Use keto diet to release the fluids from your body 😉

[@learnelectronics]

Thanks but I have a board certified cardiologist who specializes in CHF.

[@Devin82m]

@@learnelectronics Yeah, unless that Cardiologist is suggesting Keto, then he's just going to kill you, literally. Keto will fix a number of health issues, I've seen it with my own eyes with my wife who was pretty overweight, had horrible insomnia, and a few other issues. I would strongly suggest you watch Dr. Eric Berg's videos here on KZbin about congestive heart failure, he is the real deal and explains why most doctors are wrong on a number of issues and how they often suggesting things that will do the opposite of heal you. Great videos by the way, and I didn't mean to go on on this subject, but noticed the comment and wanted to agree.

[@taniorganik4702]

Good luck

[@Rocks740]

Can you draw Bistable MV using 555 timer and Op Amp.

[@MichaelElstien]

Hello, I am looking to design a circuit that is battery driven to turn on a door courtesy light on my experimental airplane. My plane has gull wing doors that open over the wing. I would like to have the courtesty light turn on when the door is open and off when it closes. I want it to be self contained because it is really hard to run wires from the door to the fuselage and keep them watertight. I was thinking of using a tilt switch to signal when the door is almost all the way open, wait 2-3 seconds and then turn on. Why the wait: I do not want turbulence while flying to activate the light. I also want the light to turn off after 2-5 minutes. Again, the desire is to have this completely self contained, maybe a 1-3 watt LED, battery operated. The light would light up the wing walk area during loading or unloading at night. I was thinking the tilt switch would be what supplies power to the entire circuit, starting the 1-3 second delay and the 2-5 minutes off timer. When the door closes, the tilt switch would cut power to the circuit, resetting it. being a mech Engineer, I can package it all up but designing the circuit to be as simple as possible is not in my skill set.

[@learnelectronics]

email me, [e-mail]. Ill help you. PP/SEL, IA here by the way.

[@irgski]

how abt the “un-stable”?

[@bjl1000]

Have fun now with these leaded components. Soon will come a day when it is not economical for manufacturers to make them . Then the electronics hobbiest will be gone.

[@markclark787]

Signetics FULLY ENCODED, 9046 X N, RANDOM ACCESS WRITE-ONLY-MEMORY, Signetics Write Only Memory 25120 Datasheet