hybridfree/eevblog-posts huggingface dataset:
Electromagnetic reality check - Page 1
Forum section: electronics / beginners

author: Quantumplate
author_rank: Regular Contributor
timestamp: May 08, 2023, 08:26:38 am
content: I wrote this bit in my notebook some months ago after coming across the flyback converter. Now i'm not sure about the last line's reasoning "this reverses one of etc..." .Is it right, and if not, what would be a succinct way of putting it?

author: wasedadoc
author_rank: Super Contributor
timestamp: May 08, 2023, 09:53:17 am
content: Inductors oppose changes of current. Immediately after the switch is opened the current in the primary wants to keep flowing in thesamedirection. The diode polarity allows that. The polarity of the voltage across the primary reverses.

author: MathWizard
author_rank: Super Contributor
timestamp: May 09, 2023, 11:59:17 pm
content: If you were to plot the current through an inductor vs time, it will be continuous, in the sense that it can't make a sudden jump. So if you choose an instant of time, and moved along the graph, the value at that instant, will be the same, as you approach from either side of that point. The voltage across a capacitor also must be continuous.But for that to be true, an inductor will automatically change the voltage across itself, to keep the current flow the same. So the plot of the voltage, can have a jump, at a point in time, like from +12V the moment before the sw is opened, and then jump/step to -12V the moment after the switch opens. And so then the current just before and after, maintains the same magnitude and direction, but then it will decay as the magnetic field loses energy to external resistance or internal non-ideal effects, like the coil's resistance.And an ideal capacitor, in order to have a continuous voltage, it's current can jump to any value it needs, to maintain the voltage the same, at an instant in time.If you pass a big current through some inductor, and then open the sw, the voltage builds up to the point that some leakage or even air itself, will conduct for a moment, and be seen as a spark. And then make radio waves too.
Electronic article surveillance (EAS) system receiver antenna.. mixer? - Page 1
Forum section: electronics / beginners

author: nergal
author_rank: Contributor
timestamp: April 08, 2015, 01:28:03 pm
content: Hello,I've been a lurker on this forum for quite some time, and a big fan of Dave's videos. I am coming to you now with my first question.I've been working on reverse engineering the receiving block of an 8.2Mhz EAS system working with soft tags.I am having a problem understanding how the small module below functions. (photo and circuit attached below)The idea is this:I have one coil that emits discreet frequencies around 8.2Mhz. And 2 coils that check if there is something resonating in the proximity (soft tag or hard tag). The two signals from the receiving coils are mixed with the circuit above into one signal, but i do not understand how it is done. The two coils are connected to the 4 pin terminal and the two pin terminal is sent directly to the sensor board. (everything after R33 is on the receiver board)I measured the values of the coils with a network analyzer and from my calculations they do not resonate even close to the emitted freq (8.2Mhz). So I believe there is something more subtle going on but cant put my finger on it. The transformers are 1:1 from the measurements. The values are actual values on the board.This being said I am happy to hear your opinions, and sorry for the English mistakes, I am not a native speaker.
Electronic ballast for fluorescent tubes 8 - 144W | Need Help - Page 1
Forum section: electronics / beginners

author: Abhijit#2020
author_rank: Newbie
timestamp: December 06, 2020, 10:44:29 am
content: Hello Friends,I was trying to build this Electronic ballast for fluorescent tubes 8 - 144W circuit but could not able to get to it. I am not sure what type of capacitor I have to use. What IC I need to have and the transformer. |OPlease Guide me.Thank you.Abhijit

author: Circlotron
author_rank: Super Contributor
timestamp: December 06, 2020, 11:23:57 am
content: Post the details of the ballast so we don't have to guess.

author: Abhijit#2020
author_rank: Newbie
timestamp: December 08, 2020, 05:16:24 pm
content: It's a 144-watt total output CFL connected with AC input supply 250v 50KHZ
Electronic ballast power supply - Page 1
Forum section: electronics / beginners

author: oliver602
author_rank: Regular Contributor
timestamp: May 02, 2022, 06:23:53 pm
content: HiI'm trying to understand the rectifier and associated circuitry in this electronic ballast.Why are there so many diodes and capacators?D5, D6, D7, D9, D10, C8, C9, C11, C12edit, corrected schematic

author: jonpaul
author_rank: Super Contributor
timestamp: May 02, 2022, 10:22:38 pm
content: What type of lamp/LED: Fluro, CFL, incandescent halogen, HID, etc?Been designing and consulting since 1975 on electron9c ballasts and SMPS.What is the ballast Model and mfg of ballast you try to copy or reverse engineer?Most have:EMI filter, PFC, 360V bus at rect.360V bus >> 1/2 or full bridge HF >> load matching L/C>>lamp.LV like LED and inc need step down trsf.You makde just a very paertial schematic, of the front end. You omit the heart of the HF sectin, bridge, inductors, transformersPlease carefully re-examine and draw complete circuitJon

author: Feliciano
author_rank: Frequent Contributor
timestamp: May 02, 2022, 10:28:26 pm
content: Agree. Please check your diagram and the polarity of the diodes.Normally you use capacitors and diodes ladders as a voltage doubler or multiplier, but if we follow your previous drawing it would seem to work like a voltage divider. But anyways probably there's something wrong with that schematic, so please check.

author: oliver602
author_rank: Regular Contributor
timestamp: May 03, 2022, 08:27:14 pm
content: It's a T8 2x58W ballast.Howlonger LGT8258D-A2C2 failed. I replaced both electrolytics C1 and C2. C2 vented again within a minute.I'm sure the schematic I have drawn so far is correct, spent a fair bit of time on it. I'll check it and draw some more.

author: oliver602
author_rank: Regular Contributor
timestamp: May 07, 2022, 06:41:53 pm
content: I have corrected some of the schematic. There are two transformers, two TO-220 transistors, a 3 pin IC, a small inductor with 3 windings along with a bunch of passives for the output which I still have to draw.

author: Zero999
author_rank: Super Contributor
timestamp: May 08, 2022, 10:01:36 am
content: I presume more diodes are connected in series to boost their voltage rating. It will work with D5 & D6 and D9 and D10 can be one diode if nothing is connected to where they're joined.Analyse the current paths through the diodes and capacitors. C1 and C2 are charged in series and discharged in parallel.The output waveform will have troughs in it at half the mains peak voltage.This rectifier has a higher power factor, than the usual bridge & smoothing capacitor and the capacitors only need to be rated a half the peak voltage of the mains.

author: Terry Bites
author_rank: Super Contributor
timestamp: May 08, 2022, 03:40:33 pm
content: https://www.electrical4u.com/electronic-ballast/The diodes are 600V- it makes sense to use two in series if you've got a kV or more of striking voltage.

author: oliver602
author_rank: Regular Contributor
timestamp: May 22, 2022, 07:13:23 pm
content: I completed the schematic. Sorry it's a mess and probably has some mistakes.
Electronic books recommendation and some advice - Page 1
Forum section: electronics / beginners

author: Metonymy
author_rank: Newbie
timestamp: January 03, 2018, 05:04:48 pm
content: Hello,I was introduced to electronics and electrical engineering in the first year at the university. I'm currently studying Computer and Software Engineering.I'm thinking about studying more on my own and I was thinking to purchase the following books:- Microelectronic circuits Textbook by Adel Sedra and Kenneth C. Smith- The Art of Electronics Textbook by Paul HorowitzI already own Fundamentals of Electric Circuits by Charles K. Alexander and Matthew N.O. Sadiku, this book made me like electronics and electrical engineering by the wonderful explanations and problems that it has, but.. I don't think that I will be able to obtain a career in this field, I lack a lot of fundamental knowledge, experience and in my area most of the jobs that I'm aware of are software engineering oriented, however I still wanna learn electronics as a hobby, while doing software engineering for a living.I have no idea what projects should I try nor how big is this field and what are all the things that you can do.Right now I'd like start learning how to use Eagle or KiCad and design a simple PCB.What other books or resources would you recommend me to look into?

author: rstofer
author_rank: Super Contributor
timestamp: January 03, 2018, 05:15:26 pm
content: Check out the stickies at the top of this forum."Learning the Art of Electronics" is the lab manual for "Art of Electronics".If you check out the US Bureau of Labor Statistics for electrical engineers versus software engineers, you will find that software engineering has many more opportunities.https://www.bls.gov/ooh/architecture-and-engineering/electrical-and-electronics-engineers.htmhttps://www.bls.gov/ooh/computer-and-information-technology/software-developers.htmIt's regrettable that BLS lumped electrical engineers (utility and commercial electrical systems) with electronics engineers. They are two completely different fields and should have been separated.
Electronic Component Management - Page 1
Forum section: electronics / beginners

author: twjtwj
author_rank: Contributor
timestamp: August 12, 2013, 03:32:31 pm
content: Can anyone recommend a good electronic component manager? I have a bunch of parts organized in bins, but would like something to keep track of the details.For example:- Lists all parts and where they are located (which bin, etc.)- Also lists what the part is useful for (op amp, high output, etc.)- Attach datasheets- Search that will let you find a part by it's type, use, and other attributes (like audio, high output, volt range, etc.)- Anything else I missed that you think would be usefulI ran across this (http://partkeepr.org/) but it runs off of PHP/MySQL (which I can do, but I'd rather have Windows).Thanks.

author: Sigmoid
author_rank: Frequent Contributor
timestamp: August 12, 2013, 03:38:21 pm
content: Yep filing the things has started to become a chore... I wonder how veterans do that...

author: Unknown
author_rank: Unknown
timestamp: August 12, 2013, 05:35:46 pm
content: This has been discussed several times before, for example:https://www.eevblog.com/forum/projects/software-project-component-inventory-manager/https://www.eevblog.com/forum/beginners/electrical-parts-inventorymanagement-system/https://www.eevblog.com/forum/chat/what-do-you-use-to-manage-your-coponents-stash/Running a PHP/MySQL stack on Windows should be quite easy using something like XAMPP.

author: shebu18
author_rank: Frequent Contributor
timestamp: January 05, 2014, 09:07:06 pm
content: I've got partkeepr running under windows and also created a directory tree, added footprints, and added parts to it. until now every thing is great.

author: Kohanbash
author_rank: Regular Contributor
timestamp: January 05, 2014, 11:47:55 pm
content: Quote from: Sigmoid on August 12, 2013, 03:38:21 pmAs a veteran who has a home lab and has a full electronics lab at work (we do R&D and not production), I can not say that we do it much better. We still have lots of draws with parts.Our primary organization is that each cabinet has a category (passives, connectors, etc..) and each draw has a label with what is in it.Within each draw each compartment has a label with what is in it as well as the part number so we can order more when the compartment gets empty.
Electronic Components for Audio/Recording Help - Page 1
Forum section: electronics / beginners

author: JRTreetop
author_rank: Newbie
timestamp: October 29, 2020, 06:28:17 pm
content: Hello,I am completely new to using any forum of any kind. I have been working on a project and was directed to come here and ask you my questions.I have been searching for a sound/recording/playback device that can fit into a space (in a toy) preferably no bigger than an inch. It will be used for a project I am working on for my children who are 2, and 4 years old so it needs to be somewhat child safe (whether it's battery operated or rechargeable).I have searched through Alibaba, Amazon, and anywhere I can think of on the internet for devices but so far have only come across items that record for 10, 15, 60, or 120 seconds for example EZ sound box (amazon), and sound chips on Alibaba.What I need is something that can record for at least 10-15 minutes minimum and can can loop potentially at various settings for 30 min, 1 hour, or "infinity" until it is shut off (or even 8 hours would be fine). I am picky with sound because I find a lot of the sound chips I have seen/bought are all junky/muffled sound. I am looking for something with clear playback AND that fits in a small space AND that can be fairly simple to use.I hope someone on here can point me in the right direction. This world of electronic components is completely new to me!!Thank you in advance and be well!
electronic components  - Page 1
Forum section: electronics / beginners

author: dikkombe
author_rank: Newbie
timestamp: November 14, 2011, 01:50:07 pm
content: Hi,people i have a few questions1-all integrated circuits perform the same work?2-transistors are all the same work?3-when I'm building a circuit have to choose any circuit or have to choose the specific one?how to classify the circuits?-thx!!!!

author: Unknown
author_rank: Unknown
timestamp: November 14, 2011, 02:07:36 pm
content: Jumping in to prevent the flames.1 - No, although some perform similar functions or multiple times a function.2 - Very broadly, yes. However different characteristics between them make them useful in very different applications.3 - You can classify circuits by their intended function, e.g. alarm system, flashlight, radio receiver, power supply etc.
Electronic Course for the Complete Newbie - Page 1
Forum section: electronics / beginners

author: David Cutcher CEG
author_rank: Contributor
timestamp: July 24, 2019, 09:02:30 pm
content: :-+New Course on Udemy.com -Electronic Circuits for the Evil GeniusIt isspecifically for beginnerswho are interested in learning electronics, but don't know where to begin.If you recognize kirchhoff, this is not for you.Newbies only, please -OR- Refer a friend.SPOILER ALERT = You do needmy text (on Amazon)components.a multimeterI approach this as a teacher, not as a Techie.This course is "Hands-On" right from lesson 1, and 1st circuit in lesson 3.My explanations are not deeply technical, but technical enough.Attached are Learning Objective for the course. My email is ElectronicsWithDavid(at)gmail.comEmail me for more details.David Cutcher "Certified Evil Genius"

author: JustMeHere
author_rank: Frequent Contributor
timestamp: July 25, 2019, 06:43:11 am
content: Honestly, go through all of Daves videos.Start here:https://www.eevblog.com/fundamentals/I've learned a ton from Dave.Also MIT has some online videos of classes, but I've found them hard to watch.This dude has some cool stuff:https://www.youtube.com/user/w2aew
Electronic load as current limiter - Page 1
Forum section: electronics / beginners

author: Leon16
author_rank: Newbie
timestamp: January 16, 2018, 01:52:46 pm
content: Can I use my electronic load to limit the current in a circuit in case something goes wrong by connecting it in series with the load circuit??

author: Zero999
author_rank: Super Contributor
timestamp: January 16, 2018, 02:12:45 pm
content: Please provide more information.What electronic load?What device?Electronic current limiting should not be used in place of a fuse or proper circuit breaker.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 16, 2018, 02:35:36 pm
content: Lacking any further detail, and given the considerations above -- probably yes.That's essentially what my last gadget does,https://www.eevblog.com/forum/projects/finished-current-limiting-breaker/msg1373360/#msg1373360with an added time-out feature so that it opens the circuit eventually.But it's made for bidirectional operation (doesn't matter which way you connect it up), has protective devices to control overcurrent and overvoltage, and filtering (partly for operation, but also so it doesn't mind what the circuit around it is doing).An electronic load might be missing some of these features, might not appreciate carrying reverse current or overvoltage, might not respond that fast (or responds too fast and becomes unstable on some loads), etc.Tim

author: Leon16
author_rank: Newbie
timestamp: January 16, 2018, 02:49:34 pm
content: As electronic load I am using the IT8211 and as supply I am using a 11.1v lithium battery pack

author: Leon16
author_rank: Newbie
timestamp: January 16, 2018, 02:53:01 pm
content: My load should not pass any reverse current through the electronic load and i will makes sure to not reverse the connections of the electronic load ,Tanks
Electronic load input circuitry and mains earth isolation - Page 1
Forum section: electronics / beginners

author: electricar
author_rank: Regular Contributor
timestamp: December 19, 2016, 01:40:17 pm
content: Hey folks,I’m designing my own electronic dc load and am wondering if anybody can show me the right input circuitry. I know from several designs, that you should take into account the inductance of the leads from your power supply to the dc load. This is e.g. done with a RC-snubber (e.g. 1R and 4,7uF in series from the positive dc load input to the negative).You can see in Dave’s #862 - BK Precision 8601 DC Electronic Load video that there are two 1R power resistors and also two big capacitors (see "BK Precision Load Input Components.PNG"). Where do you have to place the second snubber? Is this simply in parallel to the first one?Also there are two MOVs and two other capacitors. Does anybody know where they are exactly placed (I assume between the positive and negative load inputs)?Do you know how to dimension them and what the exact purpose is? I assume classic ESD and transient protection on the inputs?Another question is concerning the isolation of the load inputs and the mains earth and the connection between them.On the HP 6060B electronic load there is this connection (see "HP 6060B Input Circuitry.PNG").Mains earth and the positive floating load input (+BUS) are connected through a 22nF 250VAC capacitor. Mains earth and the negative floating load input (-BUS) are connected through a 22nF 250VAC capacitor and a 10Meg resistor in parallel.What is the purpose of this connection? Okay, it’s not a direct connection of the negative terminal and mains earth, but is this enough high impedance to be called “floating”?If I connect a mains earthed power supply to those “floating” inputs, the isolation of the primary interface (mains earth referenced) and the secondary interface (floating) from the block diagram (see "HP 6060B Block Diagram.PNG") will be bridged, won’t it?Could this lead to any unintended function states?Thank you very much in advance!electricar
Electronic Load - Page 1
Forum section: electronics / beginners

author: requim
author_rank: Regular Contributor
timestamp: October 31, 2011, 08:04:19 am
content: I've been acquiring power supplies. Apparently it's become my thing. Working or broken, as long as it's used I've been looking at them. Anyway, I've been looking at electronic load devices and I wanted to know more about them. The primary reason why I'm looking at them is because I want to test the loads, and I'm not really sure how else to do it. I know I can measure current and amperage off of them with a multimeter, but I'm assuming an electronic load device is used to pull a steady load off the device as a burn in tool or something. Is that right? Is there more to them than that? The one thing I do know about them is that they appear to be pretty pricey!Any suggestions on a good one?

author: Unknown
author_rank: Unknown
timestamp: October 31, 2011, 11:30:33 am
content: Dave made a video about how to build a dummy load, this may be helpful. Your DMM in current mode represents almost a direct short and dissipate almost no power, a dummy load will dissipate the power. It can either be constant or sometimes modulated (to test transient response/stability). The current and/or voltage it draws is often variable.

author: hacklordsniper
author_rank: Frequent Contributor
timestamp: October 31, 2011, 12:34:40 pm
content: For arround 300-400 $ you can buy a programable dummy load (300 V, 30 A, ~180 Wmax), soon i will recieve one from iTech and do a review.

author: requim
author_rank: Regular Contributor
timestamp: November 01, 2011, 04:21:22 am
content: I wouldn't mind going the DIY route. I watched Dave's video and if his design could be modified to handle 4 amps or so from 0 - 35 volts that should handle everything I want to test for now. Has anybody built one spec'd similiarly or has anyone seen a good schematic for one??

author: Balaur
author_rank: Unknown
timestamp: November 01, 2011, 04:43:18 am
content: Quote from: requim on November 01, 2011, 04:21:22 amI've built something like this at some point and I've still have it around. Mine draws up to 3 and something amps and dissipates safely about 100W.There are some tricky stuff you may want to be aware of:- you need an opamp that's not afraid to drive capacitive loads- and a transistor with a low input capacitance- but your design may still oscillate at some operating point.- it's better to have a transistor with a low Vgs(th) - logic level FETsCheers,Dan

author: kripton2035
author_rank: Super Contributor
timestamp: November 01, 2011, 02:25:51 pm
content: siliconchip made a simple 50v-10A electronic load with simple componentshttp://www.siliconchip.com.au/cms/A_30506/article.htmlalso iteadstudio sells simple open source electronic loads as a kit:http://iteadstudio.com/store/index.php?main_page=product_info&cPath=29_31&products_id=421as you wish !!!
(Ended) Electronic motor failure - Page 1
Forum section: electronics / beginners

author: sam1275
author_rank: Frequent Contributor
timestamp: July 25, 2018, 02:07:56 pm
content: Hello.There is an AC fan that used to work constantly for a long time, it got stuck several months earlier, I took it apart and cleaned the dust and mud, then add some oil, then it recovers.But here is a second time, but this time after I make sure it can rotate freely, it still do not work, the motor just vibrates/makes low frequency sound when power is delivered, what could broke and how to troubleshoot it?Thanks.Edit: Thank you everyone.I explained everything in the latest post:https://www.eevblog.com/forum/beginners/electronic-motor-failure/msg1704047/#msg1704047

author: Andy Watson
author_rank: Super Contributor
timestamp: July 25, 2018, 02:10:14 pm
content: Does it have a capacitor?

author: Doctorandus_P
author_rank: Super Contributor
timestamp: July 25, 2018, 03:36:18 pm
content: What happens if you give the motor a spin by hand before you apply power?Does it keep rotating (in the direction you spinned it) or does it coast to a halt.Is it a low powered fan, which won't cut off your fingers?Then you might try spinning it after power is applied.

author: james_s
author_rank: Super Contributor
timestamp: July 26, 2018, 04:21:15 am
content: If it spins freely by hand but just hums when you power it, that's a classic symptom of a PSC motor with a faulty or disconnected run capacitor.

author: orbanp
author_rank: Regular Contributor
timestamp: July 26, 2018, 03:15:19 pm
content: I never had much luck fixing/cleaning the bearings of such fans.A clean/re-oil usually lasted about two weeks.If the bearing/fan got stuck, after a while the thermal fuse would let go.Those bearings are bush-type synthered bronze bearings, soaked with oil.Just adding extra oil does not seem to work.May be if you would boil the bearing in oil it would help. Or just get new bearings.But then it gets to the point where it is simpler/cheaper to get a new fan, at the end that is what I did.EDIT:I did try grease as well, did not really help either.Good luck, Peter

author: james_s
author_rank: Super Contributor
timestamp: July 26, 2018, 03:18:54 pm
content: I've found that adding grease instead of oil sometimes works well, so long as the bearing has not worn badly from running dry. I used automotive wheel bearing grease.

author: Neomys Sapiens
author_rank: Super Contributor
timestamp: July 26, 2018, 10:48:31 pm
content: Quote from: Doctorandus_P on July 25, 2018, 03:36:18 pmJust saying.

author: sam1275
author_rank: Frequent Contributor
timestamp: July 27, 2018, 10:54:01 am
content: Sorry for the late reply.Yes it has a capacitor in serial.It's not a high powered one that will hurt me.It had a extremely weak force to rotate, not easy to feel.However everything ended today, after I took off the screws, I pulled it apart, and yes it's really apart, the wire just break completely and everything are in a very aged state that lots of rubber/plastic parts flies everywhere.I think that's because the long time jamming made the motor too hot. RIP...Thank you everyone.
Electronic on/off touch sensors  - Page 1
Forum section: electronics / beginners

author: electronics-whiz
author_rank: Regular Contributor
timestamp: August 08, 2017, 02:21:24 am
content: So a while back I scavenged a pair of Quantum 205.2X170mm date: 03-02-2001, 0171-1741-0330. Touch sensor PCB with lights from an old Apple/ IMAC monitor. I think would be cool to re-use these, but I can't find any info on these. I also think if I wanted something like this I could get something fairly cheap, maybe even that is just a sensor, transistor with on/off that can then drive a relay, or work with an Arduino, etc. Trying to see if these apple boards are worth keeping or if they would be more a pain. Also curios what is out there for simple touch sensors that could trip a relay, etc.
Electronic programmer’s model? - Page 1
Forum section: electronics / beginners

author: Richardcavell
author_rank: Contributor
timestamp: March 04, 2023, 03:02:40 pm
content: For CPUs, there is a concept of a programmer’s model. There are registers, and an instruction set, for example. You program the CPU that is modeled and it should work out.But we know that modern CPUs actually do register renaming, and transform the instruction stream into whatever language they really use internally. So the programmer’s model is maybe a hypothetical thing.I’ve been learning about the signals that go in and out of the CPU. Is there an equivalent of the term programmer’s model for the hardware?Richard

author: tooki
author_rank: Super Contributor
timestamp: March 04, 2023, 03:39:35 pm
content: Block diagram?

author: pcprogrammer
author_rank: Super Contributor
timestamp: March 04, 2023, 05:07:00 pm
content: datasheet?

author: Benta
author_rank: Super Contributor
timestamp: March 04, 2023, 08:23:20 pm
content: Quote from: Richardcavell on March 04, 2023, 03:02:40 pmCPUs have done this forever: microcode in the beginning; instruction breakdown to microinstructions and, and, and...It's totally uninteresting to the user, who will use the normal instruction set (i386, AMD64, 68K. PowerPC, whatever).It's a thing for the chip designers and architects. It's a bit like "I've heard that the pistons in my Austin Allegro uses a certain alloy for the pistons. Should I care?"

author: tggzzz
author_rank: Super Contributor
timestamp: March 04, 2023, 08:40:29 pm
content: Quote from: Richardcavell on March 04, 2023, 03:02:40 pmJust as there is no single software programmers model, there are a number of "layers" in hardware specification, design and implementation.This is astartingpoint:microcoderegister transfer level (RTL), synchronous logicgate level, asynchronous logictransistor and interconnect levelelectron and electromagnetic wave levelThe last is the most physically accurate model, must be used in some circumstances, but is overly complex for reasoning about system behaviour.Each preceding "higher" level is a simpler model of the lower level that abstracts important behaviour which is only valid in some circumstances.Different modelling and simulation tools are used at each level.
Electronic smoke tracing - Page 1
Forum section: electronics / beginners

author: Infraviolet
author_rank: Super Contributor
timestamp: February 14, 2024, 01:06:00 am
content: Is there any common method for finding out where the "magic smoke" escaped from, when the circuit it came from still appaers to be working?I've been working on a slow speed sinusoidal BLDC driving circuit, (a commercial 2A 12V wall wart, no lithium batteries or high current supplies, powers my circuit setup which takes the form of a buck converter like system which recirulates a a much bigger current at lower voltage within the motor's coils) and whilst running it noticed a hint of something that looked like magic smoke drifting in the beam of a desk lamp, no sign of exactly where it came from. And I got a faint whiff of that unmistakable burnt component smell. I cut the power, tried wiping my finger around various components for an "ouch", no heated spots. I gingerly turned it back on again, and it all seemed to run properly, no more smoke visible.But I'm sure it was electronic component smoke I saw and smelled.The circuit is presently on a stripboard (veroboard) with some short single core wire pieces running between different sections.I don't have a thermal camera. Any idea how I might diagnose where the smoke came from, so I can correct the circuit design so it won't happen again, potentially becoming a proper "magic smoke-->dead components" incident if it does. As I said, everything seems to be working still, so I can't just locate a dead component.Thanks

author: Bud
author_rank: Super Contributor
timestamp: February 14, 2024, 01:33:01 am
content: Could be an electrolytic capacitor vented its stuff from below. Can be difficult to locate unless lifted.

author: Manul
author_rank: Super Contributor
timestamp: February 14, 2024, 08:21:59 pm
content: If magic smoke shows up, but the device still works, most of the time it's resistor. Look for discoloration.
Electronic Starter for Metal Halide Lamp 250W with DC? - Page 1
Forum section: electronics / beginners

author: rentner
author_rank: Regular Contributor
timestamp: June 07, 2014, 11:25:59 pm
content: Can you actually run a Starter on DC, or will it destroy something? Also, would it work with a higher voltage? I mean, the average voltage in Germany is 230V RMS. Rectified it gives you 325V. Would that work or overpower the lamp and starter? It has a container with some Transistors and 1 big Inductor with iron core.Do they run with DC? And do they even accept the peak voltage permanent?I just don't like the flickering of it. It makes it almost impossible to use it succesfully as a big room lighting.

author: Legit-Design
author_rank: Frequent Contributor
timestamp: June 08, 2014, 12:00:29 am
content: rectified it will still be 230V average? It will still flicker at same rate if you don't add big amount of capacitance or cut the tops off and turn them into heat. Or did I miss something? The lamp itself will probably work off DC once it's started, the starter will probably need to be replaced to one that works off DC stated so by manufacturer.

author: rentner
author_rank: Regular Contributor
timestamp: June 08, 2014, 02:06:23 am
content: Of course filtered with Caps. So this electronic Starters/Balasts will not work with DC. That answers the question...It must be electronic at least. There is a tiny Box with Input and Output. On the backside just 2 Wires go to the big Box which propably is a huge inductor. How do this Starters/Balasts work?

author: SeanB
author_rank: Super Contributor
timestamp: June 08, 2014, 10:32:36 am
content: The general purpose MH lamps will not run well on DC, as the one electrode along with the glass seals will be destroyed by electrolysis from it. You will need a HF ballast to get flicker free operation ,which replaces the magnetic ballast and the starter. The ballasts are available from most large electrical wholesalers or from Osram or Phillips directly, you just have to ask for a ballast for the particular model of lamp. Will give a flicker free output, but must be mounted quite close to the lamp and with adequate cooling to give best reliability. As a bonus it can generally restrike a hot lamp in a shorter time.
electronic style looking smiles - Page 1
Forum section: electronics / beginners

author: archil
author_rank: Contributor
timestamp: March 16, 2021, 08:17:41 am
content: How about asking for smiles, to add more, but more electronics style?

author: Benta
author_rank: Super Contributor
timestamp: March 16, 2021, 11:48:30 am
content: This is not Instagram.Making posts unreadable by plastering emojis all over them is not productive. Save that for pictures of your food.

author: archil
author_rank: Contributor
timestamp: March 16, 2021, 02:24:25 pm
content: keep your mind away from my food. p.s. i don't have instagram.
electronic switch - Page 1
Forum section: electronics / beginners

author: giorgik
author_rank: Contributor
timestamp: July 23, 2015, 02:48:46 pm
content: Hello to all.I have a circuit of this type (see attachement circuit 1)where I use a resistor of 12K and a photoresistor LDR. The output of the signal is taken at A and sent to the base of a TIP107 (PNP darlington transistor).Is there a way to reverse the polarity of the power supply circuit according to an external signal that presents two voltage values so as to have, as in attachement circuit 2 ?

author: PSR B1257
author_rank: Frequent Contributor
timestamp: July 23, 2015, 02:59:51 pm
content: QuoteWhat are you looking for? This explanation is abitlot confusing.

author: giorgik
author_rank: Contributor
timestamp: July 23, 2015, 05:16:42 pm
content: Yes. To achieve this you can use a mechanical switch (see attachment), however I would like to use an electronic switch controlled by an external signal.

author: PSR B1257
author_rank: Frequent Contributor
timestamp: July 23, 2015, 06:00:07 pm
content: QuoteThats what relays are made for. Or you can use a electronic switch (according to the topic) like a CD4066

author: giorgik
author_rank: Contributor
timestamp: July 24, 2015, 09:26:28 am
content: thank you PSR B1257, I will use the CD4066 that is just what I was looking for.
electronic switching of 120v AC line to one of 4 taps. - Page 1
Forum section: electronics / beginners

author: BlackICE
author_rank: Regular Contributor
timestamp: September 01, 2020, 10:02:42 am
content: I want to use a micro-controller to switch the speed of a blower fan that using a split phase motor with 4 taps for 4 different RPM settings. So I need to connect one side of the AC power line to 1 of the selected taps. Current load is rated at 7 amps. Peak is probably higher but not specified.Using 2 spst relays in series works for 3 speeds. Probably using 2 dpdt can do 4 speeds, but I have to give it some thought. 4 triacs with opto isolators. Any other ideas?This will be used to control a typical blower inside of a HVAC system. Does anyone know the how the power consumption changes with RPM for this type of motor. The desire to control the speed is for lowering the noise and power used when maximum speed isn't needed.

author: Ian.M
author_rank: Super Contributor
timestamp: September 01, 2020, 10:39:49 am
content: Consider using pulse transformers for isolation as multiple TRIACs firing would be disastrous, and if the input side of a pulse transformer is shorted (by its half-bridge driver) its output side will be low impedance, reducing the risk of false triggering. The TRIACs will need a generous voltage rating and probably RC snubbers across them, again to reduce the risk of false triggering.

author: ledtester
author_rank: Super Contributor
timestamp: September 02, 2020, 12:55:13 am
content: What's the motivation for using triacs over the relays?If you decide to use triacs, I would first look into using commercially available solid-state relays -- which are essentially an optocoupler and triac.

author: BlackICE
author_rank: Regular Contributor
timestamp: September 02, 2020, 10:07:12 am
content: I guess I will stick to relays. SSR cost more and need heat sinks. Also read they can fail closed which would be bad.
Electronic workbench - Page 1
Forum section: electronics / beginners

author: Dr.Morgus
author_rank: Newbie
timestamp: May 01, 2013, 12:54:54 pm
content: I posted the other night on how to set up and use the virtual center tap transformer in multism(EWB).when I try to use it no matter how I set the parameters it still does not work

author: MacAttak
author_rank: Unknown
timestamp: May 01, 2013, 05:06:08 pm
content: You should follow-up on the original thread instead of creating a new one. Adding extra forum threads just makes the system more difficult and confusing to use.https://www.eevblog.com/forum/beginners/ni-multisim/msg225287/#msg225287
Electronics Acronym Utopia - Page 1
Forum section: electronics / beginners

author: ADC-1995
author_rank: Regular Contributor
timestamp: January 23, 2016, 06:20:49 pm
content: This site has about every acronym you can think of regarding electronics. I stumbled upon it and it looks very thorough. I posted here as it looks like the proper place to be, but admin please move if needed as this applies to all levels of expertise.http://www.abbreviations.com/acronyms/ELECTRONICS/
Electronics book recommendations - Page 1
Forum section: electronics / beginners

author: fixit7
author_rank: Regular Contributor
timestamp: June 02, 2019, 01:04:45 pm
content: I started reading Understanding Basic Electronics by Larry Wolfgang.He explains well and keeps it interesting.Good chapter on algebra to help with things like Ohms law.I am looking for book recommendations also that have actual circuits, soldering techniques, and other hands on help.Thanks.

author: tggzzz
author_rank: Super Contributor
timestamp: June 02, 2019, 01:32:13 pm
content: Quote from: fixit7 on June 02, 2019, 01:04:45 pmhttps://www.eevblog.com/forum/beginners/electronics-primers-course-material-and-books/Soldering techniques are one of the few topics thatcanbenefit from a video. This lot is succinct and shows how to do it welland badly:https://www.youtube.com/playlist?list=PL926EC0F1F93C1837

author: rstofer
author_rank: Super Contributor
timestamp: June 02, 2019, 01:33:07 pm
content: I think "Getting Started in Electronics" by Forrest Mims does a nice job.Videos re: just about anything you can imagine are on YouTube - including soldering. Look especially at SMD soldering and 'drag soldering'.

author: garethw
author_rank: Regular Contributor
timestamp: June 02, 2019, 01:33:49 pm
content: I'm currently studying Electronic Engineering at uni and have a couple of books that I turn to. Firstly is "Electronics: A Systems Approach" by Dr. Neil Storey.I also have "The Art Of Electronics 3rd Ed" by Horowitz & Hill and the accompanying "Learning The Art Of Electronics" by Thomas Hayes. Hayes' book has circuits to build and study in great depth.The Art Of Electronics (AOE) is possibly the most detailed book out there,but, it has so much in it that it can be a difficult book to read as a beginner. I'm starting to find it more useful at the end of my first year at uni.As far as soldering skills, I don't know of any books. For me personally I like to just get on and have a go. I learn huge amounts by screwing stuff up with my own hands.
Electronics Book - Page 1
Forum section: electronics / beginners

author: majorkuso
author_rank: Contributor
timestamp: October 11, 2012, 10:29:49 pm
content: I have Grob's Basic Electronics 9 editionhttp://www.amazon.com/Basic-Electronics-Student-Multisim-CD-ROM/dp/007827124X/ref=sr_1_6?s=books&ie=UTF8&qid=1349920038&sr=1-6&keywords=Grob%27s+Basic+ElectronicsI am thinking of getting the 11 editionhttp://www.amazon.com/gp/product/0077410092/ref=ox_sc_sfl_title_1?ie=UTF8&smid=ATVPDKIKX0DERbut I would like to know if there is a significant difference between the two other than price before I buy it.
Electronics Calculator Spreadsheet - Page 1
Forum section: electronics / beginners

author: thomasfuhringer
author_rank: Newbie
timestamp: July 03, 2020, 08:26:15 pm
content: I am in the process of learning electronics and put together an Excel workbook that facilitates the most common calculations such as transistor biasing, filter frequencies etc. Maybe somebody finds it useful. To me it is more efficient than using those online calculators (or a pocket calculator for that matter).
Electronics components part number, how does it make sense  - Page 1
Forum section: electronics / beginners

author: sairfan1
author_rank: Frequent Contributor
timestamp: November 24, 2023, 05:36:56 pm
content: I often design PCBs with DipTrace or KiCad there are 100s of built-in (pre-built) patterns available in both of these applications.They have such a complex component name that its really hard to find one that I'm looking for, mostly its way easy for me to design my own rather than searching one.I was thinking to ask you experts if there are some patterns exist in those component names that can help us to findout quickly?

author: ataradov
author_rank: Super Contributor
timestamp: November 24, 2023, 05:54:49 pm
content: Your questions is not clear. Part numbers come from the manufacturers, so you select the part, then you can search for it directly.If you mean footprints, then you typically do the partial search. If your device is in SO-8 package, then you search for variations "SO-8", "SO8", "SOIC-8". You will get multiple matches for different body width or pad styles. Some packages would have exposed pad too. This is something you would have select based on the device datasheet and your needs. It is not that hard to go though them and pick the one you like.That being said, I personally never use standard components. And all my components have default associated footprint, so I don't have to think about it. There are only a few ICs that have the same symbol with multiple possible footprints. In most cases, it is 1:1 match and I define that at the component creation time, so I don't have to think about it later.

author: sairfan1
author_rank: Frequent Contributor
timestamp: November 27, 2023, 05:59:18 pm
content: Sorry I did not explain it well, you are right there are lots of patterns available those are easy to identify and use like MCU and some other ICs.My question was more regarding connectors, headers, terminals and some passive components.

author: ataradov
author_rank: Super Contributor
timestamp: November 27, 2023, 06:11:26 pm
content: For connectors you just have to do your best. There are so many of them and so many compatible version that it is not possible to make an obvious generic naming convention. You can usually filter by the pin count, which would limit the search. And after that just look at all available and see what looks the closest.Again, sometimes it is easier to make your own library with the few connectors you actually use.
Electronics Course/ Resources - Page 1
Forum section: electronics / beginners

author: david476
author_rank: Newbie
timestamp: February 23, 2015, 04:59:35 pm
content: I'm a moderate beginner to electronics and am interested in learning a lot more. Do you guys have any resources, online courses, books, etc... that you would recommend? Thanks!

author: Cliff Matthews
author_rank: Unknown
timestamp: February 23, 2015, 06:58:01 pm
content: Look up good man.. It's no sense to speed read all the way down to the floor.. not much down there anyway..

author: mtdoc
author_rank: Super Contributor
timestamp: February 23, 2015, 07:06:38 pm
content: Bothwww.edX.organdwww.coursera.orghave free online electronics courses - including some with hands on labs - from major universities. Highly reccomended
Electronics Course - Page 1
Forum section: electronics / beginners

author: jeremy1967
author_rank: Newbie
timestamp: February 22, 2011, 08:00:10 pm
content: Hi,I am trying to make a serious effort to get into electronics (after years of false starts with various book) and I am looking for a good resource for learning. I found this -https://www.heathkit.com/cart/index.php/core-technology/master-course-in-electronics-with-40-mhz-oscilliscope/p_11.html- whichlooksappealing due to the interactive, hands-on nature of the learning material.So, a couple of questions. Has anyone tried any of these courses from Heathkit Educational Systems and, if so, how would you rate them? Also, the particular course I've indicated in the link includes a 40MHz oscilloscope (they also offer a 25Mhz scope) but I can find little information regarding the quality. The most information I could find on specs (and not even from Heathkit's own site) was here -http://www.pestingers.net/images/Test_equipment/Oscilloscopes/SO4552_54.jpgSo, any opinions/experiences would be greatly appreciated.Thanks.Jeremy

author: saturation
author_rank: Super Contributor
timestamp: February 22, 2011, 09:30:15 pm
content: I don't know how Heathkit is now, here are some leads:http://electronicdesign.com/article/analog-and-mixed-signal/whatever-happened-to-heathkit-20689.aspxhttp://query.nytimes.com/gst/fullpage.html?res=9E0CE7DB103AF933A05750C0A964958260&sec=&spon=&&scp=1&sq=heathkit&st=cse

author: quirmche
author_rank: Contributor
timestamp: February 22, 2011, 10:47:30 pm
content: I recommend theElectronics Learning Labwritten and designed by Forrest Mims (quintessential electronics guru) for Radio Shack!http://www.radioshack.com/product/index.jsp?productId=3814337It comes with two very good books, one on Analog and the other on Digital Electronics. It comes with quite a few parts and costs about $70, not $1700!Add to that aParallax Basic Stamp 2 Microcontroller Discovery kitand your off and well immersed in hands on experimentation.http://www.parallax.com/Store/Microcontrollers/BASICStampProgrammingKits/tabid/136/ProductID/297/List/0/Default.aspx?SortField=ProductName,ProductNameYou could probably pick these up on ebay for less. Hours of learning.Regarding Oscilloscopes:Enjoy!!!!PS: sorry about the ginormous picture!!

author: Simon
author_rank: Unknown
timestamp: February 23, 2011, 06:36:52 am
content: Quote from: jeremy1967 on February 22, 2011, 08:00:10 pmLooks horribly expensive to me and does not promise much

author: ecowarrior
author_rank: Contributor
timestamp: February 23, 2011, 10:58:43 pm
content: Quote from: Simon on February 23, 2011, 06:36:52 amYeh, I've got a wife like that....

author: Unknown
author_rank: Unknown
timestamp: February 23, 2011, 11:12:04 pm
content: I thought women were the opposite, "It looks terribly cheap to me (the man has to buy it) and it looks so nice on me (aka useless)".You are lucky eco!

author: grenert
author_rank: Frequent Contributor
timestamp: February 24, 2011, 02:47:03 am
content: Wow, the screen updates on the Owon scope in the video look like they're being done by a Vic20!