hybridfree/eevblog-posts huggingface dataset:
Helper to Configure U-Blox Clone For GPS Clock Project  - Page 1
Forum section: electronics / beginners

author: t1d
author_rank: Super Contributor
timestamp: September 25, 2019, 03:51:18 am
content: Background: I am making a GPS Precision Clock using a U-Blox NEO-M8N (Clone?) Receiver, Pic18F4550 MCU and 2004 HD44780 (Clone?) LCD Display.My objective is to display the UTC Time, Local Time, Day, Month and Year. Future developments will include Battery Powered Portability and Multiple Alarms.Learning how to set the U-Blox configurations is its own large learning curve (400+ page data sheet.) I have so many learning curves already underway - Electronic circuit design, Microchip PIC MCUs, KiCad, Coding in C, etc. - that I thought it actually smart to reach out to someone else that has already conquered the U-Blox U-Center and get some help.I can hear you thinking "Aren't there already turn-key GPS Clock projects out there?" Yes, and know. I can find bits and pieces, but nothing that suits my desires completely.What is so unique about what I want that another program can not do the job? Well, I have not found the first one that addresses (battery) power management and MCU capability management from a GPS Module Configurations basis. Meaning, a whole lot of battery power and MCU processing overhead can be gained by simply turning off a lot of the GPS Module's functions...Examples- The GPS Module may need to keep up with the lat/lon for calculating the local time, but it does not need to display the coordinates.- Maybe only time sentences need to be processed. $GxZDA will work best for this application.- Maybe only one type of satellite group needs to be tracked.- Etc.As you can tell from the examples, I am well into the GPS/U-Blox learning curve. But, I am getting swamped.So, I need a person to help specifically with the U-Center configurations for the project's limited purposes... To simply go through the U-Center Configuration Menu and tell me what needs to be done for each setting, with the stated objectives in mind. That's it.If you are interested in joining in, please send me a private message. I would be glad to give/send/gratis you one of my "Pinquino-stlye" PIC18F4550 Demo Boards (USA/48/Mailing) for use in development (and to just plain keep.)Otherwise, if someone knows of a U-Blox U-Center Configurations "For Dummies" source, please tell me. I will keep trudging along, until a volunteer is found, or the project is finished.Thanks for your consideration.Progress Pictures

author: awallin
author_rank: Frequent Contributor
timestamp: September 25, 2019, 04:39:58 am
content: FWIW on linux with a recent version of gpsd (https://gpsd.gitlab.io/gpsd/index.html) there is a simple tool called "ubxtool" which allows reading/writing settings (over UART aka RS232) on a ublox receiver.This allows scripting of all the settings in a file that you can run e.g. at bootup.For the LCD display you don't need the final tens of nanoseconds of precision that fancy settings might provide - so just using the defaults should work?
Helpful Considerations for a Power Supply - Page 1
Forum section: electronics / beginners

author: LoveLaika
author_rank: Frequent Contributor
timestamp: January 03, 2024, 08:13:47 pm
content: This isn't really specific, but I wanted to get some ideas. Say you have a DC-DC converter. With regards to the input voltage of the converter, what kind of "conditions" would you want to protect it against to not ruin your design and how would you do so in general? Some ideas include below:Overvoltage: too much voltage at the inputOvercurrent: design draws too much current for partsInrush Current: design draws too much current initiallyReverse Polarity Protection: when you put in the batteries in the wrong orderI implemented the latter two in older designs, but I never thought about the first two. How would you take them into consideration? Are there any other conditions that are not on this list but should be?
Helpme to find a Battery charger circuit - Page 1
Forum section: electronics / beginners

author: mmpaaker
author_rank: Newbie
timestamp: September 08, 2018, 04:47:49 am
content: Hi I am very new to transformer winding. I want to make a my own Battery charger to charge the 12V 100Ah Lead acid battery.I hav.e got several MOT transformers and I plan to rewind for 12-0-12v then I try to wind it bifilar type finally I have end with 8v-0v-8v coz no more space to wind.I was use 10.5 AWG (mm 2.44241) Copper cable.Now the transformer giving me exact 16v. 8v-0-8v I hope it tase around 30-40 ampere due to its 10.5AWG copper cable.Now I need a perfect battery charger circuit for this transformer. With Over charge protection.if anyone having a fully working circuit diagram. please Kindly provide me.Regards

author: 6PTsocket
author_rank: Regular Contributor
timestamp: September 09, 2018, 03:27:48 pm
content: First, if you use that transformer in a 2 diode, center tap configuration there will not be enough voltage to charge the battery. Only half the transformer is working at any given time so you have a full wave 6 volt transformer. Forget about the center tap and use a bridge rectifier. With diode drops, even 12 volts might not be enough. A 12 volt battery charger transformer is more like 15 volts. With a regulator, you definitely are low on voltage. On the other hand, a 100Ah battery is best charged at 0.1C which in your case is 10Amps. Hook your transformer up with rectifiers. Try it both ways.Use an ammeter. See what kind of current you get. I think you'll need to rewind with more turns of thinner wire.Sent from my SM-G900V using Tapatalk
Helps with SMD Component Identification - Page 1
Forum section: electronics / beginners

author: fatface
author_rank: Newbie
timestamp: August 02, 2022, 04:24:55 pm
content: I am a newby to electronics, just start out with some simply repairs.I have a 27 inch BENQ monitor, the exact top half (50%) is perfect, but the bottom half has an unstable and shimmer portion of the picture, it is worst from cold but then get better after the monitor has been power on for a few minutes. It never goes away completely.The monitor panel is a M270HTN02.3 and when I place the controllerboard under a Thermal Camera, the component labelled D307 showing up hot, also hot to the touch.I think it is a Zenner Diode but can not track down the value to source for an equivalent replacement. Please refer to the attached photo for the component in question.Thanks

author: rooppoorali
author_rank: Regular Contributor
timestamp: August 03, 2022, 09:12:17 am
content: The numbering is close to this one:https://www.mouser.com/datasheet/2/849/by396-2577293.pdfBut the package does not look similar.

author: Zero999
author_rank: Super Contributor
timestamp: August 03, 2022, 11:01:17 am
content: How hot do they get? Bear in mind that most components are fine up to 100oC, or even higher, so burningly hot might not be too hot.

author: fatface
author_rank: Newbie
timestamp: August 04, 2022, 05:32:36 pm
content: It is very warm to the touch compare to other components nearby. The is what it looks like under a Thermal Camera.I think it is the component responsible for the fault.Thanks

author: Zero999
author_rank: Super Contributor
timestamp: August 05, 2022, 08:22:56 pm
content: Quote from: fatface on August 04, 2022, 05:32:36 pmThat picture doesn't mean much without the temperature scale.Even if the component is getting hotter than it would ordinarily do, it doesn't mean it's faulty. It might be a fault somewhere else which is causing it to heat up.
Henry usage - Page 1
Forum section: electronics / beginners

author: AardvarkM31
author_rank: Contributor
timestamp: November 26, 2021, 04:08:51 pm
content: Will the length of the wire used for the coils of a 1.5" diameter pvc pipe set for the AM Broadcast band, give the same performance/requirements/selectivity if this length is wrapped around a 3.5 in form?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: November 26, 2021, 04:25:11 pm
content: What dimensions would the resulting winding have?L and Q will almost certainly be different. Presumably you're working for a design that needs some nominal L, so other values (beyond of say 10% of nominal) will be bad, and lower Q would be bad. Which ones apply, I have no way to guess.Tim

author: TimFox
author_rank: Super Contributor
timestamp: November 26, 2021, 05:38:38 pm
content: In my MRI days, working on relatively low field magnets with correspondingly low RF frequencies (5 to 10 MHz), I found that the dielectric loss in PVC coil forms had a bad effect on inductorQ. Polystyrene, polyethylene, and polypropylene were much better (only polystyrene in that list is glueable), and acrylic (Lucite) was mediocre.

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: November 26, 2021, 05:49:56 pm
content: Here is a formula.https://66pacific.com/calculators/coil-inductance-calculator.aspx

author: Terry Bites
author_rank: Super Contributor
timestamp: November 26, 2021, 05:53:13 pm
content: I used scrap 180mm MDPE Gas Pipe for a LW receiver.The bigger the diameter the fewer turns so less R and more Q and a higher self resonance frequency which is hopefully out of band.

author: AardvarkM31
author_rank: Contributor
timestamp: November 26, 2021, 10:37:32 pm
content: Thanks Tim and I didn't think it would be that easy... Well I guess I will start with the Boys Beginner crystal radio book

author: AardvarkM31
author_rank: Contributor
timestamp: November 26, 2021, 10:39:56 pm
content: Yes, I am not that far along to worry about the materials. Kinda looking for a quick and Relatively easy project. Picked one a bit more complicated than I originally imagined.Thanks

author: AardvarkM31
author_rank: Contributor
timestamp: November 26, 2021, 10:41:44 pm
content: Thanks kind Sir, will give it a go!!

author: AardvarkM31
author_rank: Contributor
timestamp: November 26, 2021, 10:43:48 pm
content: Helloo and thanks, I am now getting the idea that I don't know nearly enough. Wanted to start with grabbed info from TY videos and modify. Not such a good idea.
Herelink vs Taisync vs Viulinx FX – data link stress test? - Page 1
Forum section: electronics / beginners

author: skylogic
author_rank: Newbie
timestamp: July 29, 2025, 11:12:44 am
content: Doing testing on multiple HD video links for fixed-wing drones. We’ve flown with Taisync HD and Herelink, and want to evaluate 10W Viulinx FX.Viulinx FX 10W LinkAnyone done a comparison? Looking at latency, link stability under trees, and aerial handover. Also curious if ground antenna tracking really helps.
Hermaphrodite pin headers - Page 1
Forum section: electronics / beginners

author: jtruc34
author_rank: Regular Contributor
timestamp: May 17, 2019, 08:10:32 pm
content: I'm struggling finding some pin headers like the ones in Arduinos. What I'm looking for is basically a fusion of a socket pin header and a plug pin header, with a socket on a side and a plug on the other side of the board. In other word, it is simply a socket pin header with longer solder pins so that they poke out on the other side. It doesn't seem to exist however.Or else, how could I make one with normal pin headers? How are the commonly made and why are they so hard to find?Thank you.

author: Benta
author_rank: Super Contributor
timestamp: May 17, 2019, 08:16:25 pm
content: They exist. Check Preci-DIP (from Switzerland).https://www.precidip.comNo affiliation.

author: Ian.M
author_rank: Super Contributor
timestamp: May 17, 2019, 08:21:48 pm
content: Try adding the keyword "wirewrap" to your search.Long before Arduino was even dreamed of by its creators, hardware developers built prototypes using wirewrapping, which needed long pins on all sockets, headers etc. protruding through the solder side of the board. Unfortunately, with higher clock frequencies and the gradual death of the DIL IC package, wirewrapping has gone the way of the dinosaurs.

author: Buriedcode
author_rank: Super Contributor
timestamp: May 17, 2019, 08:37:50 pm
content: The phrase you are after is "stackable" or "stacking". Although there is also "long pin header".https://www.rapidonline.com/truconnect-long-pin-header-2-54mm-pitch-single-row-10-way-19-0274The double row version was popular as the PC/104 spec, and a couple of decades ago were all the rage for dev boards with stackable boards on top - I guess they still are as its what the Arduino uses.

author: jerryk
author_rank: Regular Contributor
timestamp: May 17, 2019, 08:52:09 pm
content: I bought these off Amazon to plug raspberry pi directly into a security system board.https://www.amazon.com/gp/product/B01IRRCEBK/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1Jerry

author: ebclr
author_rank: Super Contributor
timestamp: May 18, 2019, 04:19:35 am
content: It's quite easy to findhttps://pt.aliexpress.com/wholesale?catId=0&initiative_id=SB_20190517201851&SearchText=Stacking+Header

author: pwlps
author_rank: Frequent Contributor
timestamp: May 18, 2019, 10:29:46 am
content: I got these from RS: (RS Stock No. 180-9779)https://uk.rs-online.com/web/p/pcb-sockets/1809779/?relevancy-data=636F3D3126696E3D4931384E525353746F636B4E756D626572266C753D656E266D6D3D6D61746368616C6C26706D3D5E2828282872737C5253295B205D3F293F285C647B337D5B5C2D5C735D3F5C647B332C347D5B705061415D3F29297C283235285C647B387D7C5C647B317D5C2D5C647B377D2929292426706F3D3126736E3D592673723D2673743D52535F53544F434B5F4E554D4245522677633D4E4F4E45267573743D3138302D39373739267374613D3138303937373926&searchHistory=%7B%22enabled%22%3Atrue%7D
Hex editor reccomandation. - Page 1
Forum section: electronics / beginners

author: geggi1
author_rank: Frequent Contributor
timestamp: July 23, 2022, 07:53:30 pm
content: Hi!I just got my hands on a Phoenix contacts printer.https://www.phoenixcontact.com/no-no/produkter/utskriftssystem-thermomark-card-20-1085267As this is is a flatbed printer I was thinking about using this for printing PCB.Each kind of media have a definition file. I'm more of a hardware guy and is hoping to be able to just hack the definition to be able to print 100x80mm pcb or even other boards that are 100mm wide.I have opened the definition in notepad, but it is noting directly readable.It looks like some other hex files i have opened in notepad.Any pointers in to a good and user friendly HEX editor to revers engineer the media definition file.Hints for hacking the definition file is also welcomed.

author: Gyro
author_rank: Super Contributor
timestamp: July 23, 2022, 07:56:57 pm
content: A very recent thread...https://www.eevblog.com/forum/testgear/hex-editors/

author: tooki
author_rank: Super Contributor
timestamp: January 09, 2024, 10:18:06 pm
content: Quote from: geggi1 on July 23, 2022, 07:53:30 pmDid you ever figure anything out as far as convincing it to use other media?

author: soldar
author_rank: Super Contributor
timestamp: January 11, 2024, 07:23:03 am
content: I use Hex Editor XVI32. It's old but it works for me.http://www.chmaas.handshake.de/delphi/freeware/xvi32/xvi32.htmYou can download it at other places too.It is about 500K.It is for Windows but I use it with Linux and WINE.

author: eliocor
author_rank: Unknown
timestamp: January 11, 2024, 10:28:05 am
content: HxD:https://mh-nexus.de/en/hxd/it is free and it works very well!

author: Smokey
author_rank: Super Contributor
timestamp: January 11, 2024, 10:39:17 am
content: Notepad++ has a hex editor plugin.

author: RAPo
author_rank: Super Contributor
timestamp: January 11, 2024, 12:43:04 pm
content: I use010 hex editor(pro version) andImhex

author: CaptDon
author_rank: Super Contributor
timestamp: January 11, 2024, 02:15:30 pm
content: I like the HxD also due to its ability to open very large files. I used an older editor back in the DOS / W98 days and although it was an excellent app it could only open files that could fit within the lower 640K of ram. Before BIOs could auto configure to hard drive parameters we would at times have to burn a set of Eproms containing custom hard drive settings which also meant generating the correct checksum so you wouldn't get 'Bios Checksum Error at P.O.S.T. The ASCII text symbols displayed to the right of the hex data is very helpful in locating user messages within the file or device you are working with. Sometimes simply scrolling through data suddenly reveals patterns of either data or text symbols that can reveal other hidden secrets.
Hey I just built a community to drive questions away from r/ElectricalEngineerin - Page 1
Forum section: electronics / beginners

author: renzoms
author_rank: Regular Contributor
timestamp: January 13, 2021, 08:42:58 pm
content: I got the idea from r/AskPhysics and r/learnmath.Follow r/AskElectricCircuits if you’re interested!I’ve started answering math/physics/electric circuits questions I feel comfortable with. Thanks for all the help. No expectations.
HF Transformer 101 - Page 1
Forum section: electronics / beginners

author: hamdi.tn
author_rank: Frequent Contributor
timestamp: November 08, 2014, 12:10:18 am
content: Hi,i have a flyback transformer, with turn ratio 35:2:2:8 , it's supposed to give 12VDC out of 400VDC , i intend to use it as boost , it push-pull topology, (link both secondary and use the central for the push pull )Question is , are HF transformer reversible, so if i give back those 12V with push pull so it will be (24pk-pk) will it give 800 pk-pkthe transformer am talking about is 760895631 from wurthhttp://katalog.we-online.de/en/pbs/WE-LLCR/760895731can someone please explain to me how this work.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: November 08, 2014, 03:11:16 am
content: Direct link,http://katalog.we-online.de/pbs/datasheet/760895631.pdfYes...but...That's NOT a flyback transformer.And if you're not using it in an LLC converter (whether primary or secondary referred), you're going to have nasty problems trying to use it...Tim

author: Marco
author_rank: Super Contributor
timestamp: November 08, 2014, 03:25:33 am
content: Are n1 and n3 even magnetically linked? Isn't that two transformers which just happen to reuse the central bit of ferrite? (But with no closed loop between the two.)

author: hamdi.tn
author_rank: Frequent Contributor
timestamp: November 08, 2014, 07:35:11 am
content: you both right , it's not a flyback but since it's the only category where i found a 200W one , i said why not using in a fb topology , but it's not going to work they don't seem to be magnetically linked.I do have enough powerful smps transformer from an old atx power supply , i tried to use it as a step up and i did succeed but am not sure if this work under load , i cracked open a transformer from a ups unit and it had 62:2:2 turn (i can't find anyone like it too) , but most of flyback transformer i could find have 36:2:2 , am not sure i understand the impact of turn rate

author: TheCommonCathode
author_rank: Contributor
timestamp: November 11, 2014, 01:36:06 pm
content: Looks like a transformer that's supposed to go in older LCD computer monitors to run the back light (Cold Cathodes). In fact, EL-Wire is a very good example.

author: Richard Head
author_rank: Frequent Contributor
timestamp: November 11, 2014, 01:44:37 pm
content: It's a transformer with a controller leakage inductance that is used in resonant converters such as LLC etc. The leakage inductance is resonated with a series capacitance and a variable frequency is used to control output power. The same type is used in the old "electronic transformers" for halogen globes.

author: hamdi.tn
author_rank: Frequent Contributor
timestamp: November 11, 2014, 01:51:08 pm
content: well am not going to use this transformer anyway , i designed my own push-pull transformer (using some application i found ) can't say that am 100% confident of the result this application is giving but it can do better calculation than i can
HF transformer primary volts per turn calculation - Page 1
Forum section: electronics / beginners

author: gkmaia
author_rank: Frequent Contributor
timestamp: February 11, 2020, 12:04:52 am
content: For the following core configurationN27 materialGap = 0.5mmTotal inductance factor of the core: AL = 438 nHEffective permeability of the core: μe = 207Relative permeability of the core material: μr = 2300urFrequency = 60KhzAe = 173 mm2I got 0.05 volts per turn on primary. Is that calculation correct?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 11, 2020, 01:31:57 am
content: What Bmax?I suppose it's not an insanely large core, so 100mT might be fine, 200 even (maybe not 300+ especially being closer to saturation?).In any case, V/N = 4.44*Bmax*Ae*F, or 4.0 instead of 4.44 for square rather than sine wave (volts in RMS in either case). So around 9V/turn.l_g, l_e (not specified) and the mu's have no bearing on this calculation; they are freely adjustable and independent of Bmax. (They set the current required to reach Bmax.)If instead you specify a required Lpri and Isat(min), then these data are necessary.Tim

author: gkmaia
author_rank: Frequent Contributor
timestamp: February 11, 2020, 01:45:44 am
content: Sorry, my previous calculation was a bit wrong.Hopefully this spreadsheet attached has improved. I am trying to keep my Bmax under 1500.So basically the voltage I need my primary to handle is the plot attached.
Hi, am trying to design ON/OFF switching circuit using the same push-button,  - Page 1
Forum section: electronics / beginners

author: nyame
author_rank: Regular Contributor
timestamp: December 04, 2018, 09:52:56 pm
content: Hi, am trying to design ON/OFF switching circuit using the same push-button, i tried using the circuit attached below but it does not work, will appreciate any help. thanks

author: Vtile
author_rank: Super Contributor
timestamp: December 04, 2018, 09:58:22 pm
content: magic search word is "TOGGLE".

author: Wimberleytech
author_rank: Super Contributor
timestamp: December 04, 2018, 10:39:36 pm
content: Quote from: nyame on December 04, 2018, 09:52:56 pmA D flip flop with Qbar tied to D. Resistor pullup on clock. Push button from clock to ground. To address switch bounce, RC delay from Qbar to D.

author: tautech
author_rank: Super Contributor
timestamp: December 04, 2018, 11:42:23 pm
content: First 'toggle switch 555' hit on Google:http://www.zen22142.zen.co.uk/Circuits/Switching/555toggle.htm

author: malagas_on_fire
author_rank: Frequent Contributor
timestamp: December 04, 2018, 11:55:00 pm
content: What about a transistored one?http://danyk.cz/zap-vyp_en.html

author: spec
author_rank: Frequent Contributor
timestamp: December 05, 2018, 02:41:21 am
content: UPDATE#1 2018_12_05 (simpler circuit)Hi nyameThe 555 timer is a good chip but it is not really suitable for some applications. As a result of this, the other members have given simpler and better circuits. But if you must use a 555, attached is schematic for a 555 toggle circuit for you.When the circuit first powers on, the output will be set to 0V, and the LED will be off. The first time you press and release the switch, the 555 will toggle and the LED will illuminate. The next press and release and the 555 will toggle again and the LED will go out...and so on.The circuit has built-in switch denouncing so you will not get multiple toggles each time you press and release the switch.If you press and hold the switch the 555 will oscillate. C3 defines the switch denounce inhibit. C3 also defines the frequency of oscillation when the switch is held on. You can experiment with different values of C3 to tune the circuit to your liking.Notice that the 555 Q output is not involved in the toggle function, so the Q output can be used as you wish.For a low current, low voltage role like this, the switch should have gold contacts, or other contact material suitable for low level signal switching.

author: spec
author_rank: Frequent Contributor
timestamp: December 05, 2018, 08:46:05 am
content: Quote from: malagas_on_fire on December 04, 2018, 11:55:00 pmThis is a clever circuit: so simple.I didn't realise at first that it automatically powers up in the off state and caters for switch bounce.If you hold the switch on, I think this circuit will oscillate too.

author: Zero999
author_rank: Super Contributor
timestamp: December 05, 2018, 10:03:24 am
content: Here's a version which includes a timer and can be connected in series with the load. It's not possible to make this circuit with an indefinite on time, as C3 keeps Tr1 on and there's a limit to how much charge it can hold.
Hi, did i explain the role of each components well in this amplifier circuit ? - Page 1
Forum section: electronics / beginners

author: nyame
author_rank: Regular Contributor
timestamp: September 14, 2018, 03:42:34 pm
content: Hi, please did i explain the role of each component correctly in this amplifier circuit, and please some one should also reference a book for me were i can learn more about this topic

author: Nitrousoxide
author_rank: Regular Contributor
timestamp: September 15, 2018, 01:58:28 pm
content: QuoteThe BJT is fundamentally seen as a current controlled current source in black box form. It is because the base emitter junction is forward biased, that the voltage drop is the same as a PN junction drop. Thus the voltage present on the base pin only need to be higher than this to forward bias the diode (depending on desired operation mode, you may not want this). This can be seen through the use of other biasing techniques that use a single resistor tied to (usually) the positive supply to provide a fixed current.QuoteAs previously mentioned the device can be modelled as a current controlled current source and thus when current passes through a resistor a voltage drop (or differential) is formed, this is the output voltage. It does not limit the collector current, the steady state collector current is a function of biasing (and maximum current gain). The resistor seems to simply be an output load.If you want to find the correct formula for the output/input impedance, you can refer to small signal models for BJT's.QuoteI wouldn't say emitter degeneration is for thermal stability. Again, this is where one equation can speak 1000 words. Derive/prove the correct formula and it should be self explanatory (or with the addition of a justification, much easier to explain).QuoteYes, the input and output capacitors are for DC coupling.Microelectronic Circuits by Sedra Smith is a good textbook.
Hi, did i solve this logic system equation correctly ? - Page 1
Forum section: electronics / beginners

author: nyame
author_rank: Regular Contributor
timestamp: September 15, 2018, 04:00:09 pm
content: Hi, please did i solve this logic equation correctly ? and please i need a reference book for this type of logic systems to help me learn more

author: rstofer
author_rank: Super Contributor
timestamp: September 15, 2018, 04:45:24 pm
content: Looks right to me! It looks like I may have dumped my nearly 50 year old texts. Since nobody is dealing with discrete logic, it is not as important today. Most logic designs will be done for FPGAs or CPLDs and the synthesizer tool takes care of minimization.It is difficult to get minimization from a truth table. You really need to get into Karnaugh Maps and there are videos all over Google. Just watch carefully how they lay out the rows and columns. This is the real way equations are minimized.

author: rstofer
author_rank: Super Contributor
timestamp: September 15, 2018, 05:11:26 pm
content: Re: Karnaugh MapsWhen there are two variables in a Truth Table the adjacencies are easy to see. With 3 variables it is still fairly easy but when you get to 4 variables it is quite difficult to see all the possible minimizations. That's why we use Karnaugh Maps. The adjacencies in logic are adjacent in the map. You just start circling the largest blocks of 1s irrespective of overlap.

author: Benta
author_rank: Super Contributor
timestamp: September 15, 2018, 05:55:32 pm
content: nyame, you've asked for book titles before and you were given answers.
Hi everybody - Page 1
Forum section: electronics / beginners

author: atnokia
author_rank: Newbie
timestamp: June 23, 2021, 10:50:47 am
content: Hi everybody

author: Ian.M
author_rank: Super Contributor
timestamp: June 23, 2021, 11:36:23 am
content: Let me be the first to welcome you to the EEVblog forums user community.The 'New Member, Please introduce yourself' topic is. Its not mandatory, but is recommended.
Hi everyone, does a wall outlet plate need to comply with UL514D? - Page 1
Forum section: electronics / beginners

author: principleo
author_rank: Newbie
timestamp: October 18, 2019, 09:54:08 pm
content: Hi I am developing a product that includes a modified wall outlet faceplate. Upon research, I realized there's a standard called UL514D that sets safety standards for wall sockets, but I don't know if it applies to the wallplate as well (i.e. if I want to sell to big boxes like Home Depot. would they accept something without this standard)I am technically not an electronics professional but is interested in EE, I'm here to learn. Iif anybody knows relating knowledge and can share it with me I'd appreciate it a lot! Thanks!

author: soldar
author_rank: Super Contributor
timestamp: October 18, 2019, 11:19:45 pm
content: Quote

author: rstofer
author_rank: Super Contributor
timestamp: October 18, 2019, 11:20:12 pm
content: Go buy a cover plate, in a package, and see if there is a UL stamp on the plate or packaging. I doubt it!For outdoor, weatherproof plates, I would expect to see a listing. There are two varieties: One that is rated weatherproof when cords are connected and one that is only weatherproof when cords are NOT connected. This will be clearly indicated on the device and packaging.

author: mikerj
author_rank: Super Contributor
timestamp: October 19, 2019, 10:47:52 am
content: The UL-514D standard is titled "Cover Plates for Flush-Mounted Wiring Devices", which is a bit of a giveaway before you even read the the scope section of the document.

author: jackthomson41
author_rank: Regular Contributor
timestamp: October 19, 2019, 02:04:56 pm
content: There must be some standard code for this, why don't you contact some company who are already manufacturing wall plates, you can get the specs etc. It's better to learn thePhysicsof the system.
Hi everyone - Page 1
Forum section: electronics / beginners

author: Syze00
author_rank: Contributor
timestamp: October 13, 2017, 06:26:45 pm
content: I'm new to the community and figured I would say hello properly. I'm located in SE Texas (on the Gulf) around the Beaumont city area. Anyone from my neck of the woods? I'm trying to learn electronics outside of the classroom but I know enough to know that I don't know anything. Current project I'm stuck on: Fixing a Tektronix 465 scope.I think I bit off more than I can chew.....Nice to meet everyoneSyze00

author: sasa
author_rank: Regular Contributor
timestamp: October 13, 2017, 06:52:35 pm
content: You may describe what is the problem with the scope in "Repair" section.However, I would not suggest you (nor I would dare with my own limited knowledge in electronic) to repair old analog scope with CRT -high voltage deadly shock or fire risk!

author: Syze00
author_rank: Contributor
timestamp: October 13, 2017, 07:23:27 pm
content: Yeah, That's what scares me: The CRT power supply. After researching/reading about this scope everyone is saying replace the caps one way or another since they are WAY older than me (36 years). I'm just going to have to take tons of pictures to make sure I can put it back together.
Hi forum       I am having a little problem with my Rigol ds1104Z  - Page 1
Forum section: electronics / beginners

author: barak198
author_rank: Contributor
timestamp: December 17, 2015, 11:35:05 pm
content: I am sampling the voltage from a signal generator in CH1and the voltave over a resistor (10k) in CH2there is nothing else in this circuitthe scope shows the waves as if there is a phase shift !what is the problem ?thank you

author: barak198
author_rank: Contributor
timestamp: December 17, 2015, 11:42:03 pm
content: got it !!the invert button was on...

author: Fat
author_rank: Regular Contributor
timestamp: December 17, 2015, 11:46:28 pm
content: Glad to see I'm not alone.

author: barak198
author_rank: Contributor
timestamp: December 17, 2015, 11:48:12 pm
content: I am still learning how to use it

author: dan3460
author_rank: Frequent Contributor
timestamp: December 18, 2015, 03:53:12 pm
content: Once I spent more than one hour trying to find out why my scope would not give me the trace that I was expecting, instead was giving me this noise and I could see the 60Hz background noise. I pushed buttons, check my source, click the "auto set" several times. I was about to give up when.... ta ta ta taaaamThe probe that I was using to probe the circuit was not connected to the scope, I had grabbed a spare probe!!
hi freq noise in op amp output - Page 1
Forum section: electronics / beginners

author: nikodemus
author_rank: Newbie
timestamp: December 08, 2013, 08:54:06 pm
content: I've just finished building an XR2206 based signal generator for audio stuff. Originally I planned the signal path after the generator proper to be like this:SIGNAL -> pot for amplitude -> cap -> voltage divider for bias -> TL071 as unity-gain buffer -> cap to remove the DC bias -> OUT(OUT goes to both a BNC and 1/4" jack.)Everything was hunky dory as long I was just probing it (1M or 10M probes both), but the as soon as I connected a BNC or an audio cable to the jack, I got a ton of high frequency noise (or maybe a non-noise component, not 100% sure) in the output.Probing revealed that this was confined to the op amp output. The signal itself was uncontaminated. I then discovered that the signal didn't seem to need the op amp at all, and recofigured things like this:SIGNAL -> pot for amplitude -> cap -> OUT...and now BNC and audio jack connections don't cause any unwanted noise in the output.While I've declared this DONE, and am fully intending to leave well enough alone for now, I would dearly love to understand what went wrong.Obviously there are holes the size of airplanes in my understanding, so any hints or "go read about X" would be much appreciated. (A detailed explanation along with some hand-holding would be fine too, but a key term to speed me towards enlightenment via google and literature would already be handy.)

author: Rufus
author_rank: Super Contributor
timestamp: December 08, 2013, 09:03:31 pm
content: Quote from: nikodemus on December 08, 2013, 08:54:06 pmProbably loading the opamp output with the capacitance of the cable. At high frequencies it causes phase shift of the output. Phase shift within the op-amp and the additional phase shift from loading the output combine to produce 180 degrees at some frequency and what was -ve feedback becomes +ve and the amplifier becomes an oscillator.

author: madires
author_rank: Super Contributor
timestamp: December 08, 2013, 09:46:11 pm
content: I think the problem is caused by the output stage behind the OPamp. Do you got any resistor behind the output coupling cap and ground? If not, the cable will act as a nice antenna and since the output of the OPamp is fed back to the input (high impedance) you see a lot of RF noise. To mitigate the problem please try adding a resistor (1k?) at the output to create a low output impedance. That should keep most noise coming in via the output cable away from entering the OPamp stage. The scope prove doesn't cause much trouble because it's grounded by the scope to PE.

author: lowimpedance
author_rank: Super Contributor
timestamp: December 09, 2013, 06:00:44 am
content: As Rufus stated your choice of OPAMP is not good for driving capacitive loads like the cable and it basically takes off and oscillates.A little resistance between the opamp output and the DC cap. may help to isolate the load capacitance but its not the best solution.Either leave it alone as you now have it, (be mindful of what loads you connect), or research for a better buffer amp.
Hi, how can i adjust the gain of this amplifier circuit to be like the original  - Page 1
Forum section: electronics / beginners

author: nyame
author_rank: Regular Contributor
timestamp: September 09, 2018, 04:22:41 pm
content: Hi please how can i adjust the gain of this amplifier circuit to be like the original as indicate with arrow below, i need to adjust the circuit to amplifier correct with the same original gain as indicate in the uncompleted circuit.

author: Audioguru
author_rank: Super Contributor
timestamp: September 09, 2018, 08:58:15 pm
content: They are biased differently with the original collector at half the supply voltage but the new circuit has its collector voltage too high.The new circuit has too much voltage gain which can be reduced by increasing the value of the 386 ohm resistor. When the emitter resistor value is increased then the collector voltage will drop closer to what it should be. The emitter resistor should be about 456 ohms.
Hi, how can i identify where to place my truth table input in K-map cell ?  - Page 1
Forum section: electronics / beginners

author: nyame
author_rank: Regular Contributor
timestamp: July 09, 2018, 04:43:04 pm
content: Hi, for any given truth table how can i identify where to place my input in a k map,

author: Benta
author_rank: Super Contributor
timestamp: July 09, 2018, 06:39:44 pm
content: Do you mean a Karnaugh map? Never heard of a k map.

author: rstofer
author_rank: Super Contributor
timestamp: July 09, 2018, 11:03:13 pm
content: Divide the number of bits by two and use some for the horizontal legend (across the top) and the rest for the vertical legend (down the left side).The trick when assigning values to the rows or columns is to use a Gray Code encoding such that only one bit changes between adjacent rows or adjacent columns.For your example, with just 3 bits, you could lay it out like:Code:AB |C 0 1==============00 | 0 001 | 0 111 | 1 110 | 0 1

author: nyame
author_rank: Regular Contributor
timestamp: July 10, 2018, 04:14:54 am
content: Yes, please I need to understand From basic the technics use to identify where to place input from the truth table, with a practical demonstration to enable me understand better, I mean for a given truth table how can you determine this is were your input should be in the map cell ?

author: Nitrousoxide
author_rank: Regular Contributor
timestamp: July 10, 2018, 05:08:03 am
content: You first draw out a map with Gray code for the appropriate amount of variables. For example, this is a 3 variable map:Notice how there is only one bit changing per adjacent cell. The bits simply correspond to the variables. You can group the variables however you want. i.e. A/BC or AB/C. They will give you an identical result.An example using the truth table you have provided: (please excuse the messy/quick drawing)But, as we can see there are three SOP terms that form the output function:Y = BC + AC + AB

author: rstofer
author_rank: Super Contributor
timestamp: July 10, 2018, 01:55:06 pm
content: Do you understand the minimization that happened in the sketch?Note the column where BC = 11. The vertical encirclement shows that as long as B=1 and C=1, it doesn't matter what A equals. So the output term is B&CThe bottom left encirclement shows that as long as A=1 and C=1, it doesn't matter what B equals. So the output term in A&CThe bottom right encirclement shows that as long as A=1 and B=1, it doesn't matter what C equals, The output term is A&B.Combining the 3 terms (from the 3 loops) we get B&C + A&C + A&BThere are hundreds of videos on the subject plus many other tutorials. Google can help!
HI i am a noob!  and i have a capacitor question - Page 1
Forum section: electronics / beginners

author: mkube396
author_rank: Regular Contributor
timestamp: November 18, 2013, 04:10:49 am
content: Hello Buffalo NY USA....I am new to this forum and have been watching Dave's videos for a long time and decided to join up. So I am restarting my hobby in electronics, Right not I am working on getting test equipment to fix / repair radios CB/ham all so working on my ham license but that's a different topic all to its own.right now I am working a RCI-2990 10 meter Radio that I want to recap before I send it out for a complete alignment. right now it has 5 different manufacturers of electrolytic caps in it.. because this radio is known for needing work I want to put the best caps I can in it.I am guessing I cant go wrong with the flowing caps but how would you guys put them in order from worst to best caps I didn't list are welcome as I can or other people can stay away from them.NichiconUnited chemi-conPanasonicRubyconVishayLelonI just have to say I do have trouble from time to time with spelling and some times don't look over every thing I type so I just have to ask to take it easy on me...ThanksMatthew

author: codeboy2k
author_rank: Super Contributor
timestamp: November 18, 2013, 04:51:41 am
content: Hi, and welcome to the board! Good luck with your return to electronics. It's going to be fun!The question about which caps are good ones has been asked and answered on the forum before.Check this thread...https://www.eevblog.com/forum/beginners/good-brand-caps/Cheers!

author: mkube396
author_rank: Regular Contributor
timestamp: November 18, 2013, 09:42:51 pm
content: Ok will I put an order out for Nichicon caps

author: c4757p
author_rank: Super Contributor
timestamp: November 18, 2013, 10:15:05 pm
content: When I need high quality caps, I don't go strictly by brand. I filter for the brands I am willing to trust (UCC/Nippon, Nichicon, Panasonic, sometimes CDE, sometimes Vishay, sometimes EPCOS), then choose among them, looking more at rated temperature and lifespan than brand. Depending on capacitance and voltage rating, I usually end up with about 50% Nichicon, 30% UCC and 20% Pana. Pay attention to impedance/ESR (anything in a DC-DC converter should have low impedance and high-rated ripple current, and remember that low impedance is notalwayspreferable - many analog circuits, sometimes including linear regulators, are designed to assume that the electrolytics will have relatively high ESR).Quote from: mkube396 on November 18, 2013, 04:10:49 amHello, and condolences from Elmira.

author: mkube396
author_rank: Regular Contributor
timestamp: November 19, 2013, 04:17:20 am
content: Quote from: c4757p on November 18, 2013, 10:15:05 pmO ok thanks that is some thing I was not aware of and ill keep note of..and hello neighbor
Hi, i which to know 2 safety legislation applicable in this type of workplace ? - Page 1
Forum section: electronics / beginners

author: nyame
author_rank: Regular Contributor
timestamp: August 03, 2018, 12:39:54 pm
content: a domestic electrical rewiring operations, Identify 2 health and safety regulations that maybe applicable in this type of work environment with their key features.

author: drussell
author_rank: Super Contributor
timestamp: August 03, 2018, 03:20:57 pm
content: Sounds like you're asking people to do your homework for you... ??

author: nyame
author_rank: Regular Contributor
timestamp: August 04, 2018, 01:50:08 am
content: Not really, but I need some guide lines,on OSHA or HSE regulations that maybe applicable in that type of work environment

author: rstofer
author_rank: Super Contributor
timestamp: August 04, 2018, 10:03:58 pm
content: You have two threads running on this forum.I replied in the other one.

author: Jwillis
author_rank: Super Contributor
timestamp: August 05, 2018, 12:29:06 am
content: Me too.
Hi i which to know if i solved this logic system equation correctly !  - Page 1
Forum section: electronics / beginners

author: nyame
author_rank: Regular Contributor
timestamp: August 25, 2018, 03:24:18 pm
content: Hi, please i wish to know if this logic equation was solved correctly and please can any one recommend a book that deals with this kind of logic systems ?

author: Benta
author_rank: Super Contributor
timestamp: August 25, 2018, 03:56:48 pm
content: Your approach looks OK, the truth table approach works for a limited number of variables, above 4 it starts getting tedious. Not to mention when you start adding storage or sequential logic.My reference book is William I. Fletcher, "An Engineering Approach to Digital Design"

author: rstofer
author_rank: Super Contributor
timestamp: August 25, 2018, 05:30:22 pm
content: I didn't resolve the system but it looks ok to me.Aren't you supposed to write the output equation?Almost any logic design book will deal with this kind of thing in the early chapters. The next step is Karnaugh Maps and that will just about end the discussion of static logic. Following that will be sequential logic and this is where all the real work is done.Then it's on to CPLDs and FPGAs; nobody is using discrete logic for anything of any size.

author: Karlo_Moharic
author_rank: Regular Contributor
timestamp: August 25, 2018, 07:39:36 pm
content: Any book on boolean algebra will do
Hi, i wish to know if i calculate the gain of this amplifier graph correctly  - Page 1
Forum section: electronics / beginners

author: nyame
author_rank: Regular Contributor
timestamp: September 06, 2018, 03:47:02 pm
content: Hi, i wish to know if i calculate the gain of this amplifier graph correctly

author: sdouble
author_rank: Frequent Contributor
timestamp: September 06, 2018, 06:43:21 pm
content: seriously ?

author: Zero999
author_rank: Super Contributor
timestamp: September 06, 2018, 07:02:08 pm
content: Quote from: nyame on September 06, 2018, 03:47:02 pmI told you before. Don't make duplicate threads.I've already answered here:https://www.eevblog.com/forum/beginners/hi-i-wish-to-know-if-this-transistor-amplifier-circuit-simulation-is-correct/msg1804052/#msg1804052

author: Simon
author_rank: Unknown
timestamp: September 06, 2018, 07:06:25 pm
content: Quote from: nyame on September 06, 2018, 03:47:02 pmIf you post another duplicate thread you will be banned by me!
Hi, i wish to know if this transistor amplifier circuit simulation is correct ?  - Page 1
Forum section: electronics / beginners

author: nyame
author_rank: Regular Contributor
timestamp: September 06, 2018, 03:35:54 pm
content: Hi please i which to know if i build and simulated this transistor circuit correctly looking at both graphs

author: Zero999
author_rank: Super Contributor
timestamp: September 06, 2018, 03:45:52 pm
content: What requirements do you have for the gain and source impedance?The most obvious error is the polarity of the 22µF capacitor is backwards, which the simulator probably didn't spot. In real life it won't blow up, but it will upset the DC operating point, because it will conduct DC.

author: nyame
author_rank: Regular Contributor
timestamp: September 06, 2018, 03:52:14 pm
content: the gain requirement is 4

author: Zero999
author_rank: Super Contributor
timestamp: September 06, 2018, 07:25:13 pm
content: The gain will be a little higher than that: about 4.4.Other than that and the polarity of the 22µF capacitor, the circuit is good.
Hi, please how can i simulate this nand gate circuit using my truth table ? - Page 1
Forum section: electronics / beginners

author: nyame
author_rank: Regular Contributor
timestamp: May 15, 2018, 06:13:54 pm
content: Hi, please how can i simulate this nand gate circuit using my truth table ?

author: rstofer
author_rank: Super Contributor
timestamp: May 15, 2018, 08:32:29 pm
content: It seems to me the equation is: B + (A & C') + (A' & C)I don't have a decent way to draw the schematic so I'll write equations with temp outputsNand(A & A) -> temp1 - create A' - invert the 3 inputsNand(B & B) -> temp2 - create B'Nand(C & C) -> temp3 - create C'Nand(A & temp3) -> temp4Nand(C & temp1) -> temp5Nand(temp2 & temp4 & temp5) - create output D3 inverters, 2 2-input NAND gates and 1 3-input NAND gate.I think that's right...

author: nyame
author_rank: Regular Contributor
timestamp: May 16, 2018, 01:27:49 pm
content: Thanks for your respond Sir,please if you can manage to put up the diagram it will help me, i can better understand it with diagram,thanks

author: rstofer
author_rank: Super Contributor
timestamp: May 16, 2018, 01:59:21 pm
content: Quote from: nyame on May 16, 2018, 01:27:49 pmSee attached. You need to verify the Truth Table.

author: nyame
author_rank: Regular Contributor
timestamp: May 16, 2018, 04:53:25 pm
content: thanks it worked
Hi, Please how do i rest fault F0002 in ABB ACS 150 DRIVE - Page 1
Forum section: electronics / beginners

author: nyame
author_rank: Regular Contributor
timestamp: September 23, 2019, 11:38:24 am
content: Hi,Please i wish to know the parameters to enter in other to reset F0002 in ABB ACS150 Drivewill appreciate any help.Thanks