#1730

Episode 1730
I build the thru hole version of a 555 timer IC
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[@frankowalker4662]

Love the pin headder. Brilliant idea. Usagi Electric built a valve version of the 555. LOL.

[@kokodin5895]

i once needed 555 timer in a hury so i made one on a vertically mounted perf board from chinese bc547/557 transistor clones i had a bag laying around and it still works :] i would post photos if youtube wasn't very link sensitive

[@BrainBlister]

Great you’re doing this kit.

[@KeritechElectronics]

555 and 741, the true classics. I wonder if EMS will release others, like 317 etc.

[@kensmith5694]

LM117 please. None of this commercial grade temperature stuff.

[@romainchristophe1796]

Génial. Bonne année 2024

[@RommudohDev]

Oh yes, I still have a similar board lying around wainting to be assembled. It has SMD components and pin headers that can be pugged into breadboard or for use with DuPont cables...

[@kensmith5694]

In one of the applications where I used a 555, I hung a zener on the pin 5. The 5K set the current in the zener, give or take some supply voltage variations. The circuit was a booster making 12V out of 9V. The collection of Rs and Cs made it do this: If the 12V is high enough nothing happens, If it goes too low the voltage divider connected to the trigger would fire the 555. The ground end of the divider for trigger went to the pin-7 "discharge" A capacitor from pin-7 to ground slowed its rise but at some point it would hit the zener voltage and the Q would go low. A capacitor on the pint-3 "trigger" made it so that the Q would stay low a bit even if the output was too low. The circuit was well over 30% efficient. The switching didn't make enough EMI to interfere with my electric drill. The load regulation was less than a thumb width.

[@EEE-iw3fk]

You could easily modify the board to increase the output current. The IC outputs 200mA, which makes the chip awesome. I built a turn signal blinker for my ebike, just enough to drive the led's. The light stays on when it's not blinking, much safer than commercial relay blinkers.

[@kensmith5694]

www.mouser.com/datasheet/2/54/tip36-49435.pdf Less need to put in current limiting.

[@curtkeisler7623]

So cool. Thanks for doing this!

[@pauldery7875]

I see 25 I think, it's on the lower left corner. Cool item. Thanks for sharing 😊

[@kwazar6725]

Imsai 8080. Cpm. Ur 5 yrs older than me. Ics using discrete components.. love it

[@davidkclayton]

I Prefer boards that I can see the traces over pretty painted boards.

[@Manf-ft6zk]

Just as the 5k gives the name. There is the CMOS version which I prefer when possible which could be called "100100100" for the100k divider but it is simply something like LMC555.

[@VoidHalo]

The 5k resistors are not why it is called a 555. In fact, the resistors in my NE555s are 6k each. You can measure them with a voltmeter between VCC, control and/or ground. There are no protection diodes, so you measure the resistors directly. The whole story about how it got its name is anachronistic. In reality, it's actually rather difficult to get the value of a resistor exact in an IC (chip). So, most ICs depend more on the RATIO of resistances, rather than the absolute value. In the case of the 555, with the ones I have with 6k resistors, as long as all of the resistors are 6k, it will still work just the same because it's a resistor voltage divider. So, R1 provides 1/3 of the voltage, R2 provides 1/3 of the voltage, and R3 provides the other 1/3. Actually, I'll link you to an interactive circuit simulator that shows all of this. The values of the 3 resistors are 5k in the initial example, but if you right click on them and select edit, you can change the values and play around with them to see how as long as all 3 values are the same, it doesn't matter (within reason) what they are, it will still function normally. Sorry it has to be a tinyurl, but the full URL is gigantic. I assure you, it's on the up and up. It's Paul Fastad's version of CircuitMod: tinyurl.com/yp5rls7w I'd also encourage you to play around with this simulator in general. I learned so much from just playing with this. You could spend countless hours just on each of the examples. Never mind actually making stuff, yourself and experimenting without worrying about blowing anything up. I even learned to read/draw circuit diagrams without even trying. I just picked it up as I played with it. I cannot overstate how useful this has been in helping me learn about electronics, used in conjunction with textbooks and other sites, of course.

[@VoidHalo]

I forgot all about these. Wasn't there another one for the 741? I'd love to get something like that. Something about differential amps is fascinating to me. Unfortunately, I have constant issue when it comes to soldering. Whether the part doesn't get hot enough to melt the solder, or I buy a sponge just to get a plastic thing that's useless, or weird sponges that reek like bleach when I wet them. I'd like to get a temp controlled Hakko station. There's a superb documentary from the military about how to solder from the 1960s. So, I know the stuff. It's just getting it to work. Which you would think wouldn't be this hard. But that's life.

[@romancharak3675]

I just use a folded up sheet of paper towel (dry). I place my soldering Iron holder on top, so it can't escape when I wipe the iron tip on it. Dry towel does not shock the tip with cooler water of a damp sponge.

[@IMSAIGuy]

I use things like this: www.amazon.com/SINJEE-Soldering-Cleaner-Wire-type-Cleaning/dp/B08C4VN46N

[@stamasd8500]

Pfft transistors... build a 555 with vacuum tubes. Usagi Electric did. :) I won't leave a link here because YT likes to delete then, but you can find it on his channel.

[@kensmith5694]

No tuuuubes use relays

[@tvelektron]

Nice toy, i think could be useful for education.

[@Peter_A1466]

Totem pole output? And while I'm asking: dual collector transistor? Looks like three pin transistors all around, so what's up? And a happy New Year! 😃

[@p_mouse8676]

Yes, this is actually a totem pole. It's funny, because that word is also abused for most gate drivers (for like mosfets), and most of those are push-pull circuits.

[@MsFireboy2]

Question why are people so timid on SMD soldering? I have no trouble with it. Your thoughts?

[@IMSAIGuy]

I did a SMD solder video: kzbin.info/www/bejne/l6CqYmitpdSVfJYsi=__ryCsdjmnfWIb8R I do both SMD designs and thru hole ones. usually for prototype or training circuits I choose thru hole since they are a bit easier to probe and modify. for more production SMD is the way to go. A lot of people don't like working with tweezers or don't have a good microscope both make SMD easier.

[@MsFireboy2]

Thanks. I have a soldering microscope. Makes soldering SMD a little easier.

[@daveh7914]

Nice

[@fritzkinderhoffen2369]

Pretty cool.

[@chinsta00]

If you replaced the transistors with 2N7000 or equivalent FETs, would that make it a 7555? ;)

[@IMSAIGuy]

the two circuits are quite similar, you can see the 7555 schematic on the datasheet.

[@VoidHalo]

Whatever happened to the Mega6502 or whatever it was called. I remember years ago there was a project which simulated the 6502 using discrete transistors in a similar manner. But, I haven't heard anything about it in a long time. I'm not even sure if it wa meant to be sold commercially. I think it was just a private project.

[@IMSAIGuy]

monster6502.com/

[@williamogilvie6909]

Someone should write a lab book newbies can use to understand how different parts of the 555 work, eg: comparators, differential amplifiers, current mirrors, totem pole output stages, etc. There are some people who use 555 timers in everything they design. I don't. I use the 556.

[@IMSAIGuy]

cdn.evilmadscientist.com/KitInstrux/555/555_principles_rev30.pdf

[@williamogilvie6909]

@@IMSAIGuy That's a very good technical writeup on the 555, and applicable to most bipolar analog ICs. Not as rigorous as Roberge, but still useful for a lot of people.

[@joeteejoetee]

How did they simulate Q-19s' Collectors?

[@IMSAIGuy]

keep watching series

[@joeteejoetee]

@@IMSAIGuy I ALWAYS DO !

[@SkyhawkSteve]

Incredible! I had no idea that the 555's designation came from that resistor network! How many other IC's had designations that had a specific meaning?

[@humidbeing]

Most likely a coincidence. The original designers of the 555 had many other 55X parts they sold that were totally different.

[@AnalogDude_]

Cooooooooooooooooooool! 2:09 But how about @19? a transistor with 2 collectors. 4:50 you or i also have 4K99 Ohms.

[@danharold3087]

Fun stuff. I gave up on 555s some years ago. About when you could build a microcontroller circuit to do the same sort of things and more for the same cost. Always exceptions folks. Did not watch this one :) Did I miss anything?

[@willthecat3861]

No.

[@RK-kn1ud]

I wired in a 555 in monostable mode to disable my car's traction control every time I start it. I did try a microcontroller, but I had mixed results when the engine starter pulled the voltage low. I could have solved the problem but it would have taken more effort than I was willing to commit to the project. Lol. I'm a microcontroller guy, but I'd say the simplest solution is usually the best solution.

[@danharold3087]

@@RK-kn1ud Automotive is a entirely different bag of wax. Not only do you need to keep the voltage up by you have massive spikes so automotive certified/grade regulators. Yes there are exceptions. Good call.

[@Chupacabras222]

Where did you get that power board for breadboard?

[@IMSAIGuy]

www.pcbway.com/project/shareproject/Protoboard_Power_Connector_55084a5d.html

[@Chupacabras222]

@@IMSAIGuy Thank you. I'm probably going to create my own, to have top and bottom buses separate (dual rail).