Resistor substitution box project - rotary switch / knob - Page 1
Forum section: electronics / beginners

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 14, 2025, 10:28:52 pm
content: Hi,Followinghttps://www.eevblog.com/forum/beginners/resistor-substitution-box-project-power-calculation/I want to use this rotary switch from Mouser:https://www.mouser.at/ProductDetail/706-56B36-01-1-09NBut i have no idea how to select the knob for this rotary switch, i don't know how to interpret the datasheet to select the correct knob from Mouser.Can someone please help me,Thank you,

author: Analog Kid
author_rank: Super Contributor
timestamp: August 14, 2025, 10:42:30 pm
content: Since that switch has a standard 1/4" diameter shaft with a flat, any 1/4" ID knob that has a setscrew will work with it.See posts below for correction.

author: benj38
author_rank: Frequent Contributor
timestamp: August 14, 2025, 10:59:16 pm
content: The part number you chose has a short slotted shaft meant for turning by a screwdriver. The Mouser image is misleading!If you want a standard 1/8" shaft you need part number 56A36-01-1-09N. Also note that you chose solder lug connections which are what you need if you want to connect wires to the switch, If, instead, you plan to solder the switch directly to a PCB you will need part number 56P36-01-1-09N (again, this will give you a standard 1/8" shaft).@Analog Kid, looking at the data sheet it looks like this series only offers 1/8", not 1/4" shafts.

author: Analog Kid
author_rank: Super Contributor
timestamp: August 14, 2025, 11:09:42 pm
content: Oops, my bad. I misread the diagram.OP, find a switch that has a standard 1/4" shaft, not 1/8". Any 1/4" knob with a setscrew will work, whether the shaft is round or has a flat on it.

author: WattsThat
author_rank: Frequent Contributor
timestamp: August 15, 2025, 12:31:22 am
content: Nothing to do with the knob… but you should have another look at the switch ratings.What’s the maximum current you’ll pass through the resistors? 500 ma? 5V 10 ohms from the other post?What’s the current rating of the switch?Think that’s a good choice?

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 15, 2025, 07:59:32 pm
content: Hi,Yes, thank you for noticing. My mistakeIn this case, i have this option also, but i have the same problem. Can please someone help me, where do i see in the datasheet what knob do i need for this switch, it's not clear to me:https://www.mouser.at/ProductDetail/706-44A30-02-1-09NThank you,

author: Analog Kid
author_rank: Super Contributor
timestamp: August 15, 2025, 08:07:36 pm
content: I was going to point you to the datasheet for that switch--the link to it is right there on the Mouser page--but for some reason this one doesn't show the shaft diameter. Weird.But more importantly, why would you choose this very expen$ive, specialized switch?It's complete overkill for your application.They have a security feature, similar to the fuel cutoff switches on a Boeing we've heard so much about lately, where you have to push (or pull) the knob in order to change the position. Totally unnecessary for your application.Did you see the price? $69.84 for quantity one? That's ridiculous.Just pick an ordinary switch that meets your requirements (# of poles, current capacity). Chances are it'll have a standard 1/4" shaft, so you can use any knob with a 1/4" ID insert with a setscrew. Easy peasy.

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 15, 2025, 08:14:05 pm
content: Hi,I am very lost on the selection of this rotary switch. In my case, what will you choose? rotary switch and knob (from Mouser)?Thank you,

author: BeBuLamar
author_rank: Super Contributor
timestamp: August 15, 2025, 08:17:53 pm
content: https://grayhill.com/wp-content/uploads/media/42-44-drawing-01.jpgI found this drawing for the series 44 and it's 1/4" inch.

author: Analog Kid
author_rank: Super Contributor
timestamp: August 15, 2025, 08:23:18 pm
content: This onewill work.Much cheaper ($5.88).If you look atthe datasheet linked there, you see there are two possible shaft sizes: "A" = 6mm, "B" = 6.35mm.Since this part is a "B" (part # = SR2511F-0109-19R0B-E9-S-W-159), the shaft is exactly 1/4" diameter.Find any standard knob with a 1/4" insert and a setscrew and it'll work.Question: why are you even bothering with a resistor decade box? Why not just try individual resistors for your tests?

author: Analog Kid
author_rank: Super Contributor
timestamp: August 15, 2025, 08:24:34 pm
content: Quote from: BeBuLamar on August 15, 2025, 08:17:53 pmBut that's for those super-expen$ive, totally unnecessary for the OP's project switches.

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 15, 2025, 08:27:08 pm
content: Hi, based on the 1/4" inch value, i have a look on Mouser:https://www.mouser.at/c/electromechanical/hardware/knobs-dials/?q=knob%201%2F4%22%20inchbut I still have no idea what to select, will you be king to select the 1/4" inch knob from this Mouser filter link, i am very lost on thisThank you,

author: Analog Kid
author_rank: Super Contributor
timestamp: August 15, 2025, 08:36:26 pm
content: Quote from: the offset voltage on August 15, 2025, 08:27:08 pmOh, for chrissakes. That's too much hand-holding for me.Look: they have a really niceparametric searchthingie there. Meaning that you can choose the things you want (knob style, color, size, etc.), click "Apply filters" and it'll only show knobs that fit those criteria.And the knobs are shown right there below, so you can browse through them.You start with 626 knobs, which is too many to scroll through.So set one of the filters--say, black knobs only--to reduce the number. If that doesn't work, try different filters.

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 15, 2025, 08:47:42 pm
content: Thank you, now i find it

author: BeBuLamar
author_rank: Super Contributor
timestamp: August 15, 2025, 09:23:00 pm
content: But any way the switch can only handle 1A which is less than what you need for 5V at 10Ohms. Also the price is high for a device that you are really not going to use. Do you really have to build the unit?

author: Analog Kid
author_rank: Super Contributor
timestamp: August 15, 2025, 09:35:49 pm
content: Quote from: BeBuLamar on August 15, 2025, 09:23:00 pmWhat are you talking about? 5 volts through 10Ω yields 0.5A.QuoteThat's my question as well. I seem to remember the original deal was trying to figure out how to control a DC motor, or calculate its voltage/current or some such.Building a decade box is waaaay overkill for such a project.Sure, it's a nice thing to have, but it's a bit expensive to build. Maybe wait until you really need one.

author: tggzzz
author_rank: Super Contributor
timestamp: August 15, 2025, 09:37:11 pm
content: Quote from: BeBuLamar on August 15, 2025, 09:23:00 pmHe is learning a lot, fast. That's what he wants and needs at the moment.

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 15, 2025, 09:43:14 pm
content: Hi,I am self learning as much as i can from the book Principals of Electric Circuits by Floyd, and this is the application project for Energy and Power section, where i have to design a resistor substitution box.I like to build it because i also learn PCB design in parallel and i combine the theory from the book with real life PCB design, even if the project it's not 100% real life necessity i learn a lot from it. Thank you

author: themadhippy
author_rank: Super Contributor
timestamp: August 15, 2025, 09:52:43 pm
content: Id just buy an elcheapo switch, going by the first you linked to something likeshttps://www.switchelectronics.co.uk/products/ck1029-12-position-1-pole-bbm-rotary-switch-150ma-250vand move the adjustable stop to suite .And no need for a pcb,just hang the resistors off the back of the switch

author: TimFox
author_rank: Super Contributor
timestamp: August 15, 2025, 10:00:51 pm
content: I love Grayhill rotary switches, made near Chicago, but they are expensive. Here is their complete catalog:https://grayhill.com/products/rotational-controls/rotary-switches/That mechanical drawing is not confusing to those who are familiar with mechanical dimensioning, but it is in inches / (mm).Understanding drawings in that format is an excellent learning exercise for your PCB layout and box construction.The center drawing shows the shaft diameter clearly (0.125 +/- 0.002 inch = 3,18 +/- 0,06 mm), while the left drawing shows the flat section that keeps the knob from rotating on the shaft.This switch is designed for nominal 1/8 inch diameter knobs: in my experience with Grayhill, it is good to use a knob with two set-screws, one of which contacts the flat section, and the other is at 90o.Knobs with a single set-screw sometimes get hung up on the transition from round to flat with their shafts.In my retirement, I use Grayhill switches for projects, but I buy them from eBay, since the new prices are very high, even in US.Note that they have electrical variations: for a given set of pins and "throw" angles, they have different part numbers with different numbers of positions.Some have variable stops that limit the number of positions to less than the maximum.

author: Analog Kid
author_rank: Super Contributor
timestamp: August 15, 2025, 10:10:00 pm
content: Quote from: the offset voltage on August 15, 2025, 09:43:14 pmI misunderstood your needs then. A resistor box will be a nice thing for you to have.One suggestion: if you're going to the trouble to build one, select switches that will handle enough current. My guess™© would be 1A minumum. You should be able to find something not too expansive in that range.And select resistors that can handle the power: 1/2 watt or 1 watt minimum. You don't want to be letting the magic smoke out of those resistors you so carefully selected and soldered in there.Also, unless one of your course requirements is also making a PCB, don't bother: just hang the resistors on the backs of the switches, like we did in the olden days.

author: tggzzz
author_rank: Super Contributor
timestamp: August 15, 2025, 10:24:03 pm
content: Quote from: Analog Kid on August 15, 2025, 10:10:00 pmAs noted here:https://www.eevblog.com/forum/beginners/resistor-substitution-box-project-power-calculation/msg6011349/#msg6011349One thing to note is that they are 11 way, for 0 to 10. That's convenient for regular use, but may not be necessary for a learning exercise.Some N way switches can be installed in such a way that they only rotate through N-1 positions - i.e. a 12-way switch could be set to only have 11 ways. Again, that might not be necessary for this exercise.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: August 15, 2025, 10:54:52 pm
content: While decade boxes are rarely necessary, they have their uses. Easier than fumbling through bins of resistors to find the value you need for a quick breadboard, and cheaper and easier than building the huge compartment trays and sort the resistors into them.In addition to current capacity it is worth looking at the contact resistance. It will make a noticeable difference for the resistances that are worrying you about current.Another less critical, but again possibly important characteristic for your application is "Are the contacts make before break, or break before make configured." Think about what happens in your application if two resistors are connected at the same time, or if none.It is questions like these that result in the enormous number of choices that you find for these switches.Sorting by price and selecting the in-stock only options will help reduce the number of options you need to look more closely at.This seemingly simple exercise actually has quite a bit of meat for learning in it.

author: BeBuLamar
author_rank: Super Contributor
timestamp: August 16, 2025, 12:40:10 am
content: Quote from: Analog Kid on August 15, 2025, 09:35:49 pmYeah bad calculation on my part. Now I think the motor control project and this one are 2 separate projects. He ordered all the part for the motor but I doubt that it will work. I wonder what happened to that project.He so far works on 2 projects that really don't do much but do take a lot of work and money.

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 16, 2025, 05:24:04 am
content: Hi, for the motor speed controller i am now waiting for the PCB from JLC PCB. I will come back with a final update once i receive- soldier components and test the PCB.And to be honest, i don’t think that this projects are a waste of money and time, as i learn how to calculate components values, order the components, design the pcb, and i will also test the projects. As for the money, there are not many components that i have bought for this projects.

author: kripton2035
author_rank: Super Contributor
timestamp: August 16, 2025, 06:53:05 am
content: just for the records, are you aware of this ?http://kripton2035.free.fr/LabTools/lbt-resistordeca.html

author: Analog Kid
author_rank: Super Contributor
timestamp: August 16, 2025, 07:57:55 am
content: Quote from: kripton2035 on August 16, 2025, 06:53:05 amNow that is definitely cool. (Decade box using cheap thumbwheel switches.)

author: tggzzz
author_rank: Super Contributor
timestamp: August 16, 2025, 08:39:00 am
content: Quote from: the offset voltage on August 16, 2025, 05:24:04 amJust so. Listen to others, but do what is right for you.As for choosing switches, yes there is a bewildering choice - and it leads to a phenomenon known as "paralysis by analysis". That's true of many components and even everyday life, e.g. supermarkets where there my local supermarket has 42 line items of something basic like baked beans. More generally it leads designers to use components they are already familiar with, just so they don't have to spend so much time searching and evaluating.When I started the catalogue for RS components was about 15mm thick, and it was possible to look at every page to see the kinds of things available. Now it would be the best part of 1m, and they don't even print it.Some strategies that might help...Look at small web stores to see the kinds of things available. The choice will be limited, but you might even find what you want.Look at similar projects, which might have clues at to components you do (and don't) want to use.Learn how to use the search facilities, especially the terminology and filters. Each website is slightly different, but "in stock" and "price ascending" are useful. Some don't have the in stock filter, which means I look at such sites site last (yes RS, I'm looking at you). It takes time to learn the search terms, and you continually have to suck-it-and-see.For example, Farnell > Rotary switch > in stock > 12 position (near enough 11) leads to 29 items including£4.44https://uk.farnell.com/lorlin/ck1054/rotary-switch-sp12t-0-15a-250vac/dp/2797208(not a recommendation!)Overall... keep learning Hence I often look at the "reduced section" to (1) reduce the number of choices to make and (2) make me look at things I normally wouldn't even see.

author: themadhippy
author_rank: Super Contributor
timestamp: August 16, 2025, 11:45:35 am
content: Quoteas a sidenote ,the version that gives out a binary code are ideal for capacitor substitution boxes

author: kripton2035
author_rank: Super Contributor
timestamp: August 16, 2025, 05:39:18 pm
content: Quote from: themadhippy on August 16, 2025, 11:45:35 amyes see here too :http://kripton2035.free.fr/LabTools/lbt-capacitordec.html

author: BeBuLamar
author_rank: Super Contributor
timestamp: August 16, 2025, 05:50:15 pm
content: Quote from: kripton2035 on August 16, 2025, 06:53:05 amI don't think the OP want a functional decade box. He wanted to make PCB and use SMD resistors much more than how the device actually functions.

author: tggzzz
author_rank: Super Contributor
timestamp: August 16, 2025, 06:16:50 pm
content: Quote from: BeBuLamar on August 16, 2025, 05:50:15 pmHe wants to learn.He is learning, learning many things not directly related to the stated end goal. Good.He will make mistakes. We all do, even as professionals. That's why there are prototypes, then pilot plants, then production plants. One of the things he will start to learn is the various stages a projectors through, and how.to know when one stage is "good enough" and it is time to move to the next.In some senses he is doing a "spike investigation", a standard strategy for quickly working out what the most important considerations are before committing to the laborious grind of a full project. that's assuming the next thing we create isn't a simple variation on the last thing we created. I doubt the OP will fall into the standard trap of confusing 10 years of experience with one year of experience repeated 10 times.

author: Analog Kid
author_rank: Super Contributor
timestamp: August 16, 2025, 07:05:05 pm
content: I think it's safely been established that the OP does indeed want to build himself a resistance substitution box, AKA decade box.Q.E.D.

author: BeBuLamar
author_rank: Super Contributor
timestamp: August 16, 2025, 08:55:19 pm
content: Quote from: Analog Kid on August 16, 2025, 07:05:05 pmNot! he wanted to do his project which is a rather useless resistor substitution box not a decade box. The project is much more of an excercise in finding parts, designing PCB than learning Watt Law or Ohm Law.

author: Analog Kid
author_rank: Super Contributor
timestamp: August 16, 2025, 08:58:17 pm
content: Quote from: BeBuLamar on August 16, 2025, 08:55:19 pmWell, so what if it is?Who are we to begrudge their desire to design a PCB and build a project? Just as valid as learning how to compute power or to learn Ohm's Law.

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 16, 2025, 09:15:28 pm
content: This is the application project from the book.. not my fault.And to be honest, i like more the incremental increase of the complexity of the projects from the book, if it's not easy for me me to design this simple projects, i can only imagine how it is working on a very complex project with ICs and microcontrollers..I am curios if other people have started directly with complex projects from let's say a magazine like Elektor, was the learning path much better?

author: Analog Kid
author_rank: Super Contributor
timestamp: August 16, 2025, 09:22:34 pm
content: Quote from: the offset voltage on August 16, 2025, 09:15:28 pmWell, my magazine when I was growing up wasPopular Electronics, but same difference.I did try tackling some projects that were a bit complex and over my head back then. I learned from them, but I found that the simpler projects were much better for learning from. Plus the anxiety level while building them was lower, which helps.

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 16, 2025, 09:31:52 pm
content: Just curios, if someone copy and paste a projects from a magazine, what does he learn? other than design the pcb, order the components, soldering and testing..The book that i study is 95% theory and problems, many problems (some with LTspice simulations..), and only one application project at the end of the section, like this famous Resistor substitution box.

author: Analog Kid
author_rank: Super Contributor
timestamp: August 16, 2025, 09:34:53 pm
content: Quote from: the offset voltage on August 16, 2025, 09:31:52 pmDepends. Maybe nothing, as you implied, or maybe a lot, if you have to troubleshoot the circuit to get it to work, or modify it.If you're curious, you can learn a lot by analyzing a circuit from a magazine or a web site. And by asking questions about it, say on a forum like this.

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 16, 2025, 09:39:46 pm
content: Hmm, in my case, if i will design a pcb for a complex project, if i will have a problem, i will not have any idea from where to start troubleshooting, as at this moment also the circuits with transistors looks scary to me..

author: tggzzz
author_rank: Super Contributor
timestamp: August 16, 2025, 09:42:54 pm
content: Quote from: BeBuLamar on August 16, 2025, 08:55:19 pmUseless to you? Undoubtedly.But that's completely and utterly irrelevant. You aren't the "customer", and the customer decides what constitutes "useful", not some random bystander.

author: Analog Kid
author_rank: Super Contributor
timestamp: August 16, 2025, 09:46:36 pm
content: Quote from: the offset voltage on August 16, 2025, 09:39:46 pmI totally get that last part! Transistors are scary.You wouldn't be designing a PCB until you've designed, tested and troubleshooted the circuit. PCB design is about the last step in that process.To aid in the design of complex projects, you have some tools available:Circuit simulators, like LTSpice, which can show you how a circuit works without actually physically building itSolderless breadboardswhich let you physically build circuit and test itAnd of course once you reach the breadboarding stage there are pieces of test equipment to help you: voltmeters, ammeters, oscilloscopes.

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 16, 2025, 09:50:27 pm
content: Can wait to reach transistorsi think it will be very challenging

author: tggzzz
author_rank: Super Contributor
timestamp: August 16, 2025, 09:52:36 pm
content: Quote from: the offset voltage on August 16, 2025, 09:31:52 pmThere is no single thing to learn. There is no single way to learn, everybody uses multiple different mechanisms to learn.Get inspiration and ideas from a magazine. Understand how and why the circuit is supposed to work.Learn theory so that you can see limitations and extend the ideas in your own direction, and/or use part ofthiscircuit with part ofthatcircuit to do something new.BTW, that's also the way to learn to cook: use recipes, understand methods, look in your stock cupboard and work something out.Unsurprisingly that is well recognised, e.g. in books with titles like "Numerical Recipes in C".

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 16, 2025, 10:00:24 pm
content: In the book that i have, author wants like some of the problems to be checked only in LTspice. The breadboard and PCB design is only for the end of chapter practical projects.At this moment i have only a DMM and recently i receive a power supply. I will see for an oscilloscope when i will start AC

author: Analog Kid
author_rank: Super Contributor
timestamp: August 16, 2025, 10:04:45 pm
content: Quote from: the offset voltage on August 16, 2025, 09:50:27 pmGood! Keep that curiosity.Yes, transistors are challenging. They look so simple: a 3-terminal device that amplifies or switches. (They do other things too).Starting at the simple end, there's the simple formula for beta (the amplification factor):β = IC/ IBBut then there's the Ebers-Moll equation:IC= IS[exp(VBE/VT) - 1]which is where my head starts to hurt ...

author: tggzzz
author_rank: Super Contributor
timestamp: August 16, 2025, 10:09:16 pm
content: Quote from: the offset voltage on August 16, 2025, 09:39:46 pmJust so.Incrementaldesign, fabrication and debugging is a skill you need to gain. Understand a bit, design a bit, test a bit, repeat with a different bit, connect those bits together and test.As for solderless breadboards, some people swear by them; I swear at them. I've seen too many beginners become discouraged because the limitations of solderless breadboards are causing problems which don't happen with other techniques.Good techniques for early incremental experimentshttps://entertaininghacks.wordpress.com/2020/07/22/prototyping-circuits-easy-cheap-fast-reliable-techniques/ even experts such as Win Hill (author of the famous "The Art of Electronics") has been caught out by solderless breadboards' has characteristics.

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 16, 2025, 10:13:48 pm
content: I also want to buy "The Art of Electronics" after i finish with Floyd book

author: Analog Kid
author_rank: Super Contributor
timestamp: August 16, 2025, 10:16:13 pm
content: Great book.Solderless breadboards have always worked for me.I haven't dealt with any RF (radio frequency) projects, which is where you run into problems with them because of parasitic capacitance. For LF stuff they (usually) work fine.Of course, everything has its limits and "gotchas". You'll learn them as you go. A truly fine book. However, don't be fooled when they say you don't really need that much math to use it. In fact, they say in the introduction that they "only" require a "minimum mathematical prerequisite, namely some acquaintance with trigonometric and exponential functions, and preferably a bit of differential calculus".I find myself stumbling over the math in the text all the time.

author: tggzzz
author_rank: Super Contributor
timestamp: August 16, 2025, 10:17:22 pm
content: Quote from: the offset voltage on August 16, 2025, 10:00:24 pmI designed and built my first computer (a 6800 with 128 bytes(!) RAM) using only a power supply, switches, resistors plus LEDs, and a 2% analogue multimeter. See the quote in my .sigThe PCBs were just like those in this projecthttps://entertaininghacks.wordpress.com/2015/02/21/a-40-year-old-hack-disinterred/when I was a couple of years older than you.I made many mistakes, and learned many things. So will you.

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 16, 2025, 10:20:40 pm
content: That is so cool, i like it

author: tggzzz
author_rank: Super Contributor
timestamp: August 16, 2025, 10:22:52 pm
content: Quote from: Analog Kid on August 16, 2025, 10:16:13 pmHere's a subtle failure in a (nominally) LF circuithttps://entertaininghacks.wordpress.com/2024/03/16/practical-traps-with-a-one-transistor-audio-amplifier-solderless-breadboards-and-oscilloscopes/Only a resistor and a transistor; what could possibly go wrong?Manhattan is the one true prototyping mechanismUnless you require low leakage, when rats nest can be beneficial

author: BeBuLamar
author_rank: Super Contributor
timestamp: August 16, 2025, 10:26:58 pm
content: Quote from: the offset voltage on August 16, 2025, 09:15:28 pmHow long does it take you for these 2 projects already. I woud simply do the calculations, determine the values of the resistor (or wattage). Draw the schematic diagram and move on. You stuck at this too long. You need to move on with the theory.

author: tggzzz
author_rank: Super Contributor
timestamp: August 16, 2025, 10:28:28 pm
content: Quote from: the offset voltage on August 16, 2025, 10:20:40 pmI hope it provides hope and a little encouragement! More recently I turned it into a Vetinari clockBTW. Every new concept, technique, and instrument has a learning curve. Try to minimise the number ofsimultaneouslearning curves.Complex expensive test equipment can take a long time to master; simpler is better. The same is true for CAD tools.

author: tggzzz
author_rank: Super Contributor
timestamp: August 16, 2025, 10:30:23 pm
content: Quote from: BeBuLamar on August 16, 2025, 10:26:58 pmWho cares?He is enjoying himself, and balancing theory and practice. What's not to like?

author: themadhippy
author_rank: Super Contributor
timestamp: August 16, 2025, 10:34:28 pm
content: Quoteif you just build it ,not a lot,however if you read the "how it works" part of the article you'll often end up with more questions that leads you to dig a bit deeper

author: the offset voltage
author_rank: Regular Contributor
timestamp: August 16, 2025, 10:36:53 pm
content: I will design the PCB for all the application projects, i don't have any problems with that, as i like it.The time to receive the PCB from JLC PCB it's like 10 - 15 days i see, and in the mean time i continue with the theory.

author: Analog Kid
author_rank: Super Contributor
timestamp: August 16, 2025, 10:49:50 pm
content: Quote from: tggzzz on August 16, 2025, 10:22:52 pmI'm not going to argue with you here about this; for one thing, you know far more about electronics than I do.However, I'll reiterate:solderless breadboards have always worked for my projects.Including one that ran on a 1MHz clock (I was surprised when that one worked).So they're not exactly useless, as you seem to imply.Their usefulness, at least in my experience, far outweighs their problems. (Until it doesn't.)Yes, they have their "gotchas" as you point out. Namely parasitic capacitance and possible high contact resistance (or no contact whatsoever!).All part of the learning process, wouldn't you agree?Later on the OP can try out "dead bug" and other wiring variations.