hybridfree/eevblog-posts huggingface dataset:
Newbie Rigol DS1050E Question - Page 1
Forum section: electronics / beginners

author: Veramacor
author_rank: Regular Contributor
timestamp: November 25, 2009, 01:13:22 am
content: Fellow Rigol owners, or experienced O-scopers for that matter,I've been trying to zoom in on a 9-Volt battery signal's noise recently. No problem aquiring the signal (around 7.8 volts).The problem I have is when I attempt zoom in on the DC signal, by using the vertical scale knob down to say 100mv/Div, I cannot re-center the 7.8 V signal on the screen as I have reached the scale limit.Is there a way to reference the 7.8V signal on the center of the screen without the vertical scaler repositioning the signal?I'll try to explain again later if I'm making myself unclear,J

author: Zero999
author_rank: Super Contributor
timestamp: November 25, 2009, 01:20:56 am
content: You should use the AC coupling function to view an AC signal suppressed on a DC signal.To measure DC you should use a DVM which is more accurate at DC.

author: Veramacor
author_rank: Regular Contributor
timestamp: November 25, 2009, 01:49:51 am
content: Thanks that was a bit of a stumbling block!V

author: Simon
author_rank: Unknown
timestamp: November 27, 2009, 05:29:04 pm
content: to be honest your going to see more internal scope noise than the noise on a 7.8 power line so if it looks nasty: don't worry
Newbie schematics question - Page 1
Forum section: electronics / beginners

author: cole1234567
author_rank: Newbie
timestamp: February 09, 2022, 02:40:26 am
content: New hereLooking for site to find schematics some vintage.Husband and i were grand piano rebuilders for over 25 yrs. but covid and health issues closed our doors.While dealing with covid and lock downs we began to work on amplifiers , electric guitars and electric pianos.if there is anyone out there who can guide us to the good free schematics, we will be very thankful.This has been one of our major problems.Thank youjulie

author: bob91343
author_rank: Super Contributor
timestamp: February 09, 2022, 04:47:13 am
content: Well it depends. The amount of info out there is very great. You need to make a more narrow request. You can read texts on amplifier design. You can pick any of hundreds of brands and pull up schematic diagrams. There are web sites just for that.For many years I operated a repair shop and ran into an amazing variety of equipment. Some not bad, some bad. I learned troubleshooting and redesign and finding parts and adjusting bias. I worked with tubes and transistors and ICs. I grew up with tubes but enjoyed transistors.I also became a jazz musician and used my electronics knowledge for good; I never liked electronic instruments. I used my engineering degree when working in industry, before I opened the retail shop. I usually tune my own grand piano and repair my woodwind and brass instruments.I would be willing to help as much as you like, as long as you don't bite off more than you can chew.

author: jeffjmr
author_rank: Regular Contributor
timestamp: February 09, 2022, 04:48:05 am
content: See the first Repair stickie. Lots of helpful links there.Jeff

author: Shock
author_rank: Super Contributor
timestamp: February 09, 2022, 10:55:20 am
content: Googling is really the best way. That and sign up to some (non audiofool) forums where they discuss repairing and building amps etc. Then you can connect to others who have collected some over time.As your repair knowledge in electronics increases you become less reliant on schematics. An example of this is people report problems diagnosing faults in low component count circuits. It's possible to measure just about "everything" with a multimeter, oscilloscope and a capacitor esr tester. So in many cases you don't need to understand the circuit in it's entirety, just use the divide and conquer then the brute force approach.
Newbie SMPS repair - Page 1
Forum section: electronics / beginners

author: rusteee
author_rank: Newbie
timestamp: November 16, 2017, 07:22:54 am
content: Hi there.I'm new to the forum, and wondering if someone could possibly help with repairs on a switchmode power supply. The power supply is out of a canon sx80 projector. Everything seems ok, unit will turn on, lamp will glow fans kick in, but once lamp goes to strike, the unit shuts down and flashes 5 times indicating abnormal voltage was detected by the main board (replace power supply according to the service manual). Upon inspection, everything looks ok. Have tested the output voltage according to the manual, I have the 6V, 18V to the main which is in spec. When I test the high voltage, at the rectifier is 316VDC, but at the main filter capacitor its 370VDC which is then output to the ballast board. There is nothing in the diagrams I have got to say whether that is spec or not but I'm assuming that the filter cap should be sitting at 316VDC as well. Please correct me if I am wrong. What would be the next place to test? I'll try and attach a screen shot of the diagram I have aqcuired from the service manual. Sorry for the noob questions, but I'm all about the learningCheers

author: pompom
author_rank: Newbie
timestamp: September 21, 2021, 09:24:27 am
content: Hello, Do you have a service manual for this projector? Im looking for more information about the ballast circuit as well. I would appreciate it if you can share this. Cheers!

author: kripton2035
author_rank: Super Contributor
timestamp: September 21, 2021, 11:44:35 am
content: check the capacitors (for esr). when a smps can't handle the charge, it is often the capacitors
Newbie starting out with electronics. - Page 1
Forum section: electronics / beginners

author: Unknown
author_rank: Unknown
timestamp: March 18, 2010, 07:57:48 pm
content: Good evening everyone! I recently started out building my own "workshop" at home after about 3 or so years of telecommunications studies at my highschool.But, since the educational system in my country is really "down in the dumps" I didn't do so much practical stuff.Just theory and theory...ahh.My mind exploded.I guess that theory is going to help me later on, but I lack some real basic things you get from working with electronical equipment.I just bought myself a soldering iron, a breadboard, a couple of basic and multicoloured LED's as well as the most expensive part of my toolkit, my Arduino board.Since I will be heading towards a polytechnics faculty, and will become a major in this field I'm already studying, I would like to "get my hands" dirty and actually start designing boards, circuits and learning some embedded software languages.What tools/software should I start collecting?I'm guessing C/C++ is the language to go, right?Thanks alot for your time!PS: Please excuse my grammar mistakes since english isn't my main language

author: septer012
author_rank: Regular Contributor
timestamp: March 19, 2010, 07:48:50 am
content: I highly suggest you write simple C programs, then read the disassembly language until you understand the basics of the language that way you can debug harder programs on a broader range of boards without actually just starting with assembly. Check out sparkfun.com for guides and (expensive) but handy electronics and hackaday.com for inspiration.
Newbie - Switching base on bias - Page 1
Forum section: electronics / beginners

author: yosmanor
author_rank: Newbie
timestamp: June 21, 2016, 11:28:16 am
content: I need a switch that will turn on a 5V circuit when the input is zero while the circuit will remain off while the input is 5V.I have minimal education in electronics. Any suggestion is welcome.I experimented on the attached circuit without success (naturally).

author: bitshift
author_rank: Regular Contributor
timestamp: June 21, 2016, 12:25:44 pm
content: You need to use a PNP transistor like this:R2 is there to tie the base of the transistor high (off) when the base is floating.

author: yosmanor
author_rank: Newbie
timestamp: June 21, 2016, 12:50:09 pm
content: Thanks

author: rstofer
author_rank: Super Contributor
timestamp: June 21, 2016, 01:02:45 pm
content: It would be interesting to know how much current is being switched. If it's tens of milliamps, no problem. If it's tens of amps, that poor 2N3906 will go up in smoke.

author: bitshift
author_rank: Regular Contributor
timestamp: June 21, 2016, 01:04:57 pm
content: Absolutely. The 2N3906 is just what was in the first image a quick google search found. Replace with a suitable transistor.

author: yosmanor
author_rank: Newbie
timestamp: June 21, 2016, 01:16:02 pm
content: Thanks guys,The current will be 2A or less.

author: Helen95
author_rank: Newbie
timestamp: June 23, 2016, 12:36:49 pm
content: Forgive me please for butting in but where is the difference. Or rather when should I switch from 2N3906 to something more powerful?

author: bitshift
author_rank: Regular Contributor
timestamp: June 23, 2016, 02:02:32 pm
content: Each transistor will have a maximum collector current which will be listed as "Ic" in the transistors datasheet. The most basic reason to get a "larger" transistor would be when the amount of current you need to pass through the transistor approaches the maximum specified in the datasheet.

author: StillTrying
author_rank: Super Contributor
timestamp: June 26, 2016, 12:05:53 am
content: 2N3906 is 200mA Max. and that will only be if it's properly turned on/saturated, - so well below 2A.A 3A is probably needed, and the correct base current calculated.Random silly question: Are yosmanor and Helen95 both the same person.

author: yosmanor
author_rank: Newbie
timestamp: June 26, 2016, 01:52:36 pm
content: yosmanor and Helen95 are not the same person

author: Audioguru
author_rank: Super Contributor
timestamp: June 26, 2016, 03:38:50 pm
content: In the first post the load is an LED that will go up in smoke if a current-limiting resistor is missing.
Newbie to Electrical Engineering - Page 1
Forum section: electronics / beginners

author: Auggie
author_rank: Contributor
timestamp: February 18, 2010, 11:23:52 pm
content: What do you all recommend as a good multimeter that will help me in my Electrical Engineering major? I noticed in Daves reviews that there are multimeter s designed for different professions like some specifically for electricians and some for electronics. I was thinking of investing in a fluke 87. So any suggestions let me know.

author: EEVblog
author_rank: Unknown
timestamp: February 19, 2010, 12:32:14 am
content: The question is how much do you want to spend?You can get a decent meter that will do the job for say $50.In another thread on here someone got the Amprobe 38XR for $65 or something, a bargain.Dave.

author: rossmoffett
author_rank: Regular Contributor
timestamp: February 19, 2010, 03:58:26 am
content: I have an 87 now and it's nice, but I got through my electronics classes with a very cheap multimeter that didn't measure microamps. I used resistors to find my current, by taking the voltage across them. Still not ideal, but you'll find accuracy is not as important as knowing what you're doing in a university lab. I've been amazed at the grades I got for failed projects simply for thoroughly documenting what went wrong, why and what could be done to fix the situation.

author: Simon
author_rank: Unknown
timestamp: February 26, 2010, 09:33:02 pm
content: well I suppose it's one thing to get it right and another to get it wrong, figure out the problem and know how to get it right next time

author: Neilm
author_rank: Super Contributor
timestamp: March 02, 2010, 07:30:48 pm
content: If you get it right first time you will not learn anything. It is after fouling up and debugging you begin to understand. (says the guy who spent best part of a week trying to debug a circuit where he swapped the input and feedback resistors on an op-amp)

author: Simon
author_rank: Unknown
timestamp: March 02, 2010, 07:41:06 pm
content: thats is true of designing and learning to design robust equipment (I myself learnt a few harsh lessins), but there are many TV repairers that don't know a lot about electronics and could not design a thing to save their lives but they do not have to know because it's more about knowing the brands and model series and the faults inherent to each one, like a good mechanic will know the failures inherent to a particular model of car but he will not know how to design a car
Newbie to oscilloscopes-kind of. - Page 1
Forum section: electronics / beginners

author: cyberwasp
author_rank: Contributor
timestamp: January 01, 2020, 03:02:26 pm
content: I you read my new members intro you'll understand the following.For the past 2 months I've been watching tutorials on using oscilloscopes. Am slowly getting back into electronics via fixing items for friends and neighbor. I've been gathering a lot of 18650 Li-ion cells. I threw together a charger using a TP4056 module.Now to my question. Like I said I'm still learning how to use the scope. However, I watched an old Youtube video of a guy using a scope to monitor the voltage and current of the battery he was charging. I would like to do the same. I can monitor the voltage but can't find the appropriate point for the current. The tp4056 he used doesn't have the protection circuits that mine does.I would have included the link to the video but the previous forum I joined was highly offended when I did that. TIAThank you Blue skull Here's the video I referenced

author: rstofer
author_rank: Super Contributor
timestamp: January 01, 2020, 05:21:53 pm
content: Wouldn't be easier and more numerically tractable to use a pair of DMMs for this kind of thing? Scopes may be as few a 8 bits on the ADC and you may not be using all of them depending on how the front end is built. As a result, any readings you get are of limited resolution.
Newbie & Ultrasonic cleaners: Which brands to buy? - Page 1
Forum section: electronics / beginners

author: Radioman23
author_rank: Newbie
timestamp: September 24, 2021, 08:20:37 am
content: First, I am so very sorry if this has been asked ad nauseaum. I have searched, and maybe I was having a dumb day when I searched, but I didn't find much related to the core of my question.I admit I got started with SMD work Loius Rossman videos, then I found the Australian Genius and here I am, hoping to learn and with gusto. However I got my start in electronics via rebuilding vacuum tube testers & test equipment as I was able.I couldn't really work on the Radios without SOME test equipment... but that's a story for another time. This is relevant: I still work with tubes now and then. So, from Vacuum tubes to 0402( so far) SMd work,to miscellaneous mechanical cleanings, I have a wide swath of needs for an ultrasonic cleaner.When I first started watching Rossmann, he went on and on about Crest brand Ultrasonic cleaners, specifically CP500HT. I keep looking for one, but I do not know why he recommends THAT model, nor have I had much luck finding one on Ebay. SO, between tubes to SMD, as well as miscellaneous cleaning I have the core question I need you kind and intelligent folks recommendations & advice:What brands of Ultrasonic cleaners do YOU trust and/or recommend? If I can't find a crest unit, which brand will suit my needs? Which brand/model would be able to handle the above variety of cleaning needs?I am willing to spend the several hundred( or more) but I'd rather get a unit that I can trust and not second guess. Buy once, cry once.I understand that some BGA assemblies that have suffered liquid or other corrosion can be brought back to working oder with a strong enough Ultrasonic cleaning machine and the right detergent, but the details are noit clear to me. I have also found that aqueous cleaning solutions seem to be the standard, as flammable solvents cannot be safely used in ultrasonic cleaners.I have also heard that you can place a sealed container of flammable solvent & the object needing cleaning in an ultrasonic cleaner & with a water bath, clean the contents of the jar... but I have no earthly clue as to IF that actually works, or how effective it is. My current guess is a strong enough cleaning machine should still be able to clean like that, but I could be very wrong. If you feel like it, please clarify... please?Any advice& comments are sorely appreciated and thank you for your patience. I live in north, north west Georgia, USA if that helps any.Thank you and good night!( I am asking this at 4:15 AM local time).

author: DC1MC
author_rank: Super Contributor
timestamp: September 24, 2021, 08:31:05 am
content: I would say go with what profis are using, and I think Louis Rossmann is profi enough for ultrasonic cleaners, so get a Crest brand, they seem to be OK and not break your bank.Cheers,DC1MC
Newbie with a schematic for review - Page 1
Forum section: electronics / beginners

author: BuzzB
author_rank: Contributor
timestamp: June 17, 2015, 01:57:20 am
content: I'm a newbie, and new to these forums.I've designed a little circuit that will allow me to control my lawn sprinklers with an Arduino YUN.Is this the kind of place I could post the schematic so more experienced players might give me some feedback?Thanks,Buzz

author: Skimask
author_rank: Super Contributor
timestamp: June 17, 2015, 02:45:34 am
content: Only one way to find out.Post it and it'll either get feedback or get deleted.
NEWBIES PLEASE READ BEFORE POSTING - Page 1
Forum section: electronics / beginners

author: EEVblog
author_rank: Unknown
timestamp: December 28, 2013, 10:14:27 pm
content: You've got a beginner question to ask?, great, you've come to the right place!But please help us to help you. Please include as much detail as possible, and what you have already done or investigated to find the answer.Short "How does this work" questions are not proper forum etiquette.School assignment questions are ok, but show what work you have done already.Regulars, please be extra nice to beginners asking questions. Do not deride them for anything, if you can't be nice, don't post.
Newbies Second Board - comments - Page 1
Forum section: electronics / beginners

author: amwales
author_rank: Regular Contributor
timestamp: March 04, 2014, 12:10:09 pm
content: Hi AllThis is my second board in eagle, I'd appreciate some comments.I had this one manufactured by OSHPark ( quick turnaround ), the first version by iteadstudio ( slow ).I'm an electronics newbie, wannabe.The first version had less headers broken out for ADCs/GPIO and was using the internal mcu oscillator. I found the precision of the internal oscillator not quite what I hoped so I added the crystal and the shared clock.2 ( pic18f26k22 ) ICs, I2C and Serial interface ( SPI internal comms ).It's for a 18 servo Hexapod I've been tinkering with for quite a while.I'm too scared to try SMT but I know I have to eventually try it.
Newcomer - Page 1
Forum section: electronics / beginners

author: RCTM
author_rank: Newbie
timestamp: January 03, 2025, 02:22:39 pm
content: Hello everyone and Happy New Year!I'm not sure if I'm posting in the correct section, so... if that is the case, I apollogize and ask the moderator to please place it in the appropriate section.I've joind this group with the intention of learning, how to program/clone (if possible) some IC's I have. attached are some photos...Thanks in advance.Cheers

author: jwet
author_rank: Frequent Contributor
timestamp: January 03, 2025, 03:15:27 pm
content: Welcome- you're in the right spot.The LM393 is a classic, medium speed, low cost comparator. It was originally made in the 1970's by National Semiconductor which is now part of TI. You found an especially good data sheet for it. There were many app notes and guides written by national about parts like these. Experienced engineers call parts like this "jelly beans". They are reliable and very low cost, sourced by many vendors and should be the first part you look at if want to make cost effective equipment. They represent the highest value option usually. If there is something that it won't do- perhaps its too slow, draws too much current, won't operate at very low voltages, etc, you look around. There are thousands of comparators around that push the specs around in different directions for different specific needs.Dave Jones did a good video explaining "jelly beans" and I believe this was one.Good luck on your journey. People here are generally, friendly and helpful- try to make your questions clear and concise and you'll have a great resource.John

author: RCTM
author_rank: Newbie
timestamp: January 03, 2025, 03:21:22 pm
content: @jwet (John) Thanks so much for the warm welcome and confirmation :-)I appreciate thew info provided and will look into it as soon as possible.Cheers,Rod.

author: jwet
author_rank: Frequent Contributor
timestamp: February 01, 2025, 10:12:41 pm
content: Was reviewing my posts and haven't seen any activity. Has some priority grabbed your attention. Here to help.

author: BILLPOD
author_rank: Frequent Contributor
timestamp: February 06, 2025, 02:08:47 pm
content: Good Morning RCTM, welcome to the forum.

author: Laval
author_rank: Regular Contributor
timestamp: February 06, 2025, 04:12:14 pm
content: Welcome aboard !
Newest of the new...need help in design, nomenclature, etc - Page 1
Forum section: electronics / beginners

author: Hhndrsons
author_rank: Newbie
timestamp: March 15, 2025, 11:23:00 am
content: Hello all. First, I deeply apologize for any terminology that I may get wrong in requesting help. After searching extensively, I realize that my lack of electrical nomenclature is just too great. Need some help, and all is appreciated.I have completed a small automotive project, except for the wiring portion.What I've made is a small vacuum pump that will operate on the vehicle's 12v DC electrical system. This pump has an RC car brushless(sensorless) dc motor powering it. This pump needs to be powered at 2 different voltages depending on the state of either pressure or vacuum in the intake manifold of the vehicle's engine. Those voltages being 12v during pressure, and 8v during vacuum.So my question really becomes 2 questions at this point.1. How do I wire this brushless motor with the 12v from the vehicle and have it switch down to 8v when needed from that same 12v power source.2. I had thought of a hobbs switch to activate the vacuum pump originally, but that was when I thought I would just spin it continuously with 12v. Needing to also have it spin slower at 8v seems like it may not be compatible with a hobbs switch. Would I still be able to trigger the vacuum between 12v and 8v with the hobbs switch, or is there a better method that could be integrated to the whole circuit design?Many thanks in advance

author: ahsrabrifat
author_rank: Regular Contributor
timestamp: March 17, 2025, 10:45:09 am
content: Since your vehicle provides 12V, you need a way to drop it to 8V when necessary. A buck converter (DC-DC step-down regulator) is the best solution for regulating the voltage. It efficiently reduces 12V to 8V without wasting too much power as heat. You can install a 12V-to-8V DC-DC converter and switch between the two power sources.
Newbie - ICSP programming PIC16F18446 using TL866ii plus - Page 1
Forum section: electronics / beginners

author: JohnLon
author_rank: Newbie
timestamp: March 18, 2021, 10:47:20 pm
content: I bought some PIC16F18446 (20 pin dip) having thoughts that the TL866 had support for these.I cannot recall where I thought I saw the support but it's not showing up in the tool.This programer has ICSP support.Is ICSP completely standard for all PICs?Given that the TL866 has support for a lot of PIC's is it possible to use the ICSP interface to program any PIC? but specifically the PIC16F18446?I'd rather not have to buy a pikkit3 if the TL866 can be made to work,Can I destroy my PIC by experimenting with the ICSP interface?

author: JustMeHere
author_rank: Frequent Contributor
timestamp: March 19, 2021, 12:01:50 am
content: https://en.m.wikipedia.org/wiki/In-system_programming

author: MikeK
author_rank: Super Contributor
timestamp: March 19, 2021, 12:09:43 am
content: Quote from: JohnLon on March 18, 2021, 10:47:20 pmNo. That's why there's a programming document for each "group" of PICs.

author: JohnLon
author_rank: Newbie
timestamp: March 19, 2021, 12:21:17 am
content: So for example are you saying that the protocol over ICSP to communicate with a PIC16F18446 is likely different to that used to communicate with as PIC16F877?

author: MIS42N
author_rank: Frequent Contributor
timestamp: March 19, 2021, 12:28:50 am
content: Best advice I can give - save heartache and buy a programmer supported by Microchip Technology. I bought PIC16F1455. Thought about using the programmer I had but all looked a bit dodgy. Bought a PicKit3 (probably not genuine) for $25AU including postage and couldn't be happier. The PIC16F1455 wasn't supported by the so called "universal" socket so I had to set it up on a breadboard to program. Now the PIC is in circuit I added a 5 pin connector and can reprogram it any time.

author: JohnLon
author_rank: Newbie
timestamp: March 19, 2021, 12:34:58 am
content: pickit3 arriving from amaxon tomorrow

author: MikeK
author_rank: Super Contributor
timestamp: March 19, 2021, 12:46:24 am
content: Quote from: JohnLon on March 19, 2021, 12:21:17 amIt is definitely different. Those two PIC's are 20 years apart. Check out the programming specs for yourself; they're on the same page as the device datasheets.Quote from: MIS42N on March 19, 2021, 12:28:50 amOr do what I did: Reprogram the PICKit2 to handle new PIC's. I program any PIC I want now.
NFC Credit/debit card data format - Page 1
Forum section: electronics / beginners

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: January 23, 2021, 09:25:41 am
content: I am trying to understand data format and how information is stored? Trying to read it by microcontroller.I found many different formats, is their any good website explaining this the format and background communication protocol?

author: amyk
author_rank: Super Contributor
timestamp: January 24, 2021, 03:44:32 am
content: Start with ISO 7816...

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: January 27, 2021, 06:39:46 am
content: This is one protocol I found in NXP sheet.But the data format exchange is not given, from where I can download this?

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: January 28, 2021, 08:47:59 am
content: move up..
NFC Module  - Page 1
Forum section: electronics / beginners

author: abdullahseba
author_rank: Frequent Contributor
timestamp: September 06, 2015, 05:54:27 am
content: If I get an RFID module will it work for NFC? or do I have to get one that says NFC/RFID module?

author: Maxlor
author_rank: Frequent Contributor
timestamp: September 06, 2015, 06:24:51 am
content: That depends very much on the frequency the module works at. RFID can work in a wide range of frequencies, from 125kHz all the way up to the GHz range. NFC on the other hand always works at 13.56MHz. So if your module works at 13.56MHz, it'll most likely do NFC. If uses one of the other common frequencies (125kHz, 433MHz, 868MHz) then NFC isn't possible.

author: abdullahseba
author_rank: Frequent Contributor
timestamp: September 06, 2015, 09:03:50 pm
content: Quote from: Maxlor on September 06, 2015, 06:24:51 amSo all I have to watch out for is the frequency?
NFC types - Page 1
Forum section: electronics / beginners

author: carbon dude oxide
author_rank: Frequent Contributor
timestamp: May 06, 2013, 04:38:16 pm
content: Hello, im currently going threw several different projects on my list to see what i can have a go at and i have just looked into the use of Near fied communication. Sounds prety good but the downside of it is it general only works 10 cm or under away from eachother. Is there any types of NFC that can do up to a meter? If so it would give me a few projects to look into further.

author: Bored@Work
author_rank: Super Contributor
timestamp: May 06, 2013, 04:53:48 pm
content: If you don't wantNEARfield communication, why do you look at near field communication? Try Bluetooth or some of the stuff based on 802.15.4.

author: carbon dude oxide
author_rank: Frequent Contributor
timestamp: May 06, 2013, 05:06:38 pm
content: im looking for something like NFC that works just like it but at a further distance because bluetooth has to connect to devices first whereas NFC you just wave it over and doneplease correct me if i am wrong here

author: elgonzo
author_rank: Unknown
timestamp: May 06, 2013, 05:26:57 pm
content: Quote from: carbon dude oxide on May 06, 2013, 05:06:38 pmThere are bluetooth modules available that are capable of automatic pairing/connect, so you don't need to worry about manual connection. I guess, similar functions are also provided by modules for different wireless technologies...

author: carbon dude oxide
author_rank: Frequent Contributor
timestamp: May 06, 2013, 05:28:03 pm
content: ok thanks alotim going to look into this further

author: w2aew
author_rank: Super Contributor
timestamp: May 06, 2013, 11:05:56 pm
content: Quote from: carbon dude oxide on May 06, 2013, 05:28:03 pmI know a couple of people that are having a lot of fun with this very low cost wireless device - good for several meters or more, and very inexpensive:http://www.sparkfun.com/products/9582Check to see if it's legal in your locale...
NGD8205N replacement? What to look for comparing IGBTs? - Page 1
Forum section: electronics / beginners

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: March 29, 2017, 05:32:55 am
content: I have somehow ended up with an aftermarket car ECU that requires repairs.Both ignition coil drivers have gone bad, and by bad, I mean they are burnt holes in the board while desoldering themselves.As a result, there really aren't any pads to fit a replacement SMD device, so I'm looking to go TO220, and mount them to the case.But, I'm rather lost when it comes to finding a suitable part, the datasheet for the current part is here:http://www.mouser.com/ds/2/308/ngd8205n-d-304413.pdfAny advise would be fantastic! Thanks.

author: danadak
author_rank: Super Contributor
timestamp: March 29, 2017, 10:59:57 am
content: An excellent resource is usually the vendor website for tech help, especiallythings like substitutions. You need to supply application, environment,and help usually forthcoming. Schematic quite helpful.That being said a circuit design for safe area, drive, and thermal considerationsis not like picking toothpicks out of a box for gum jam relief.I would focus on gate C, Max rated breakdown voltages, operating currentand saturation voltage, speed.Regards, Dana.

author: Zero999
author_rank: Super Contributor
timestamp: March 29, 2017, 11:17:03 am
content: How do you know it's only the IGBTs which have gone bad? If they've failed that catastrophically, it's likely they've taken down other components with them.

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: March 29, 2017, 06:49:57 pm
content: I don't have a schematic, and its pretty difficult to follow traces on the board, which I suspect the manufacturer intentionally did.I don't know that its just the IGBT's, but I don't have an easy way to feed it the required signals to see if everything else is functional.I know it powers up, and will still communicate with a PC via rs232, so that's a start at least.

author: AmmoJammo
author_rank: Frequent Contributor
timestamp: March 29, 2017, 06:59:22 pm
content: I contacted the manufacturer of the ecu, and they said I could use these:http://www.mouser.com/ds/2/389/stmicroelectronics_cd00000023-329627.pdfThey did also end their statement with a question mark and its obsolete, so I'm not so sure...I was considering using these:http://docs-asia.electrocomponents.com/webdocs/13c0/0900766b813c0822.pdf
ngspice(kicad) vs LTSPICE - Page 1
Forum section: electronics / beginners

author: spicey
author_rank: Newbie
timestamp: November 07, 2021, 06:05:55 pm
content: Hello,I'm still trying to deal and understand the results of several SPICE versions and now I have a new problem simulating the same schematic, a common-emitter amplifier based on NPN 2N3904 transistor, on LTSPICE and ngspice (launched from kicad).The schematic is the same, the SPICE model too (except for two values that ngspice does not know what to do with them) but the results both numerical and graphic are very different.kicad schematic:LTSPICE schematic:ngspice(kicad) plotter output:LTSPICE plotter output:ngspice(kicad) log:(𐄂=does not match)Code:vcc = 3.000000e+01 at= 5.000000e-04𐄂 vb_min = 1.080491e-01 at= 1.452800e-04𐄂 vb_max = 5.177824e+00 at= 4.452800e-04𐄂 vb = 2.64294e+00vb_t = 4.19355e+00vin_pp = 4.999807e+00 from= 0.000000e+00 to= 0.000000e+00vin_rms = 1.76777e+00 from= 0.00000e+00 to= 5.00000e-04𐄂 vout_pp = 1.241313e+01 from= 0.000000e+00 to= 0.000000e+00𐄂 vout_rms = 4.48404e+00 from= 0.00000e+00 to= 5.00000e-04𐄂 vout_max = 5.831076e+00 at= 1.312800e-04𐄂 gain_pp = 2.48272e+00𐄂 gain_rms = 2.53655e+00gain_t = -3.60000e+00LTSPICE log:(𐄂=does not match)Code:vcc: MAX(v(vcc))=30 FROM 0 TO 0.0005𐄂 vb_min: MIN(v(b))=1.51887 FROM 0 TO 0.0005𐄂 vb_max: MAX(v(b))=6.58211 FROM 0 TO 0.0005𐄂 vb: ((vb_max-vb_min)/2+vb_min)=4.05049vb_t: (vcc*r2/(r1+r2))=4.19355vin_pp: PP(v(in))=4.99595 FROM 0 TO 0.0005vin_rms: RMS(v(in))=1.76765 FROM 0 TO 0.0005𐄂 vout_pp: PP(v(out))=17.3435 FROM 0 TO 0.0005𐄂 vout_rms: RMS(v(out))=5.95982 FROM 0 TO 0.0005𐄂 vout_max: MAX(v(out))=9.01429 FROM 0 TO 0.0005𐄂 gain_pp: (vout_pp/vin_pp)=3.47152𐄂 gain_rms: (vout_rms/vin_rms)=3.37161gain_t: -3.6=-3.6ngspice(kicad) 2N3904 model:Code:.model Q2N3904 NPN(Is=1E-14 Vaf=100+Bf=300 Ikf=0.4 Xtb=1.5 Br=4+Cjc=4E-12 Cje=8E-12 Rb=20 Rc=0.1 Re=0.1+Tr=250E-9 Tf=350E-12 Itf=1 Vtf=2 Xtf=3)LTSPICE 2N3904 model:Code:.model 2N3904 NPN(IS=1E-14 VAF=100+ Bf=300 IKF=0.4 XTB=1.5 BR=4+ CJC=4E-12 CJE=8E-12 RB=20 RC=0.1 RE=0.1+ TR=250E-9 TF=350E-12 ITF=1 VTF=2 XTF=3 Vceo=40 Icrating=200m mfg=NXP)theoretically this BJT amplifier should amplify a 5kHz 5V sinusoidal signal into a 5kHz 18V sinusoidal signal and, as you can see, everything on LTSPICE looks fine but ngspice(kicad) differs.I have two questions:1) Is there a way to reference component values (e.g. resistors or capacitors) in ngspice or LTSPICE apart from this workaround of adding parameters and defining the parameter name in curly brackets in the schematic? (I'm afraid in a real case this will affect to some others kicad's applications (as pcbnew and such)).2) Why are the plotter output and numerical results so different? Is there anything I'm missing?Any help will be appreciated, thank you.
NI DAQ on a budget - Page 1
Forum section: electronics / beginners

author: NivagSwerdna
author_rank: Super Contributor
timestamp: August 12, 2018, 11:24:35 am
content: A while back I bought a second hand NI DAQ USB 6008 and a couple of days ago I found a use for it.... I just wanted to record an analog signal at 1k samples per second for a period of 50 seconds...I downloaded DAQmx and LabView which together was about a 4GB download! And then a couple of YouTube tutorials later I captured my data all under the 45 days evaluation licence. Job done.I can see LabView is amazing but I just don't have those requirements so after 45 days I'm going to be stuck. (And to be honest I don't really want 4GB of software on my PC)Is there an easy/cheap way to get data out of my DAQ?Thanks in advance

author: JS
author_rank: Frequent Contributor
timestamp: August 12, 2018, 02:51:13 pm
content: I guess the visa commands are open, if you know them you can send via telnet or some other programs and get the answer back, Matlab could be a useful tool, you need an instrument com pakage IIRC, I could look for the package name later. Octave has that same functionality but for free.All that is useful if you are ok with coding, otherwise I don't know an alternative. I've tried with my scope and it was pretty straight forward once pc had everything installed to do so. I guess there must be a way to do it from excel directly as well.JS

author: rstofer
author_rank: Super Contributor
timestamp: August 13, 2018, 02:44:53 am
content: You'll have to do the research but it appears that you can use MATLAB. There is a Home license that isn't terribly expensive but it is not free.

author: JS
author_rank: Frequent Contributor
timestamp: August 13, 2018, 04:40:12 am
content: Quote from: rstofer on August 13, 2018, 02:44:53 amOctave is free and has basically the same functionality, while you miss some extra tools from matlab, it does a pretty nice job.JS

author: NivagSwerdna
author_rank: Super Contributor
timestamp: August 13, 2018, 09:58:06 am
content: I think PyDAQmx might be the way to go. The driver itself, DAQmx appears to be free.I do actually have a temporary (six month) license to MatLab as part of an online course I am enrolled in so I might also investigate that... not sure if my student licence covers "NI-DAQmx Support from Data Acquisition Toolbox"Thanks for the suggestions so far.
Ni-mh battery charger - Page 1
Forum section: electronics / beginners

author: mike_mike
author_rank: Super Contributor
timestamp: October 22, 2022, 04:49:51 am
content: Hello! I built the battery charger from the attached schematic. At the beginning it worked, but now when I turn the 12Vdc power on, the battery starts charging automatically (the red led turns automatically on). I wanted to start charging the battery only when I press on the button. I checked the pcb for unwanted connections but I didn't managed to find the problem.I am using TL082 instead of TL072 and BD244C instead of MJE2955.When charging (red led on) the output of opamp (pin 1) is about 1.8V and when I press the button the output of opamp is about 11.88V (the supply voltage).I use a lab power supply (linear) to power the circuit but I also used a SMPS (12v/2A), and the result was the same, it starts charging automatically the batteries.The circuit schematic is from this link:https://www.eleccircuit.com/automatic-ni-mh-battery-charger-can-make-by-yourself/The pcb is the same with the one from the link above.

author: radiolistener
author_rank: Super Contributor
timestamp: October 23, 2022, 09:45:36 am
content: If I understand correctly, it compares battery Voltage with previously accumulated Voltage on the capacitor C4. So, when battery Voltage starts to drop down, the output of comparator IC1 is changed and Q1 and Q2 are closed to stop the battery charging. It looks like implementation of -dV/dt behavior monitoring which is required for Ni-MH.So, if you want to avoid starting charge at power-on, you're needs to charge C4 before opening Q1 and Q2.
trying to figure out of this film capacitor is good or bad. - Page 1
Forum section: electronics / beginners

author: cresstt
author_rank: Newbie
timestamp: March 09, 2019, 08:57:07 am
content: hi,Im trying to fix a 90s toyota meter cluster. There's this Nichicon film capacitor which has the label "Nichicon .22 J 250 ".Image of capacitor is attached. I already googled the values to no avail.I'm trying to figure out if this cap is good or otherwise. Physically it looks ok and on the ESR meter, it reads 6.77Ω.can somebody help ?

author: cresstt
author_rank: Newbie
timestamp: March 09, 2019, 09:21:14 am
content: from further google image search of these 2 linkshttps://www.amazon.com/Nichicon-QXJ2J224KTPT-Capacitor-Metallized-Tolerance/dp/B01MZAQXZEandhttps://www.goldmine-elec-products.com/prodinfo.asp?number=G20839can I safely deduce that value is .22uf 250v capacitor ? If so, how do I determine if this a a good cap ? On the ESR meter, it reads 6.77Ω.the usual ESR matrix/table matrix smallest value starts with a 1uF and that table values are only for electrolytic caps and not for film caps.Any idea?

author: David Hess
author_rank: Super Contributor
timestamp: March 10, 2019, 04:34:22 pm
content: ESR meters are not intended to operate with such low capacitances because they rely on the reactance at the measurement frequency to be lower than the ESR.0.22 microfarads at 100kHz is 7.2 ohms so your measurement of 6.77 ohms is consistent with a good capacitor.
Nice - Page 1
Forum section: electronics / beginners

author: Unknown
author_rank: Unknown
timestamp: October 13, 2013, 12:20:50 am
content: well..i have to thx all that helped me for some questions i had and i think this blog have all the answer i need for my problems..thx alot

author: ataradov
author_rank: Super Contributor
timestamp: October 13, 2013, 12:41:01 am
content: You understand that posts must be meaningful in order to win, right? Dave is not a computer, he will look at the actual posts.

author: Unknown
author_rank: Unknown
timestamp: October 13, 2013, 12:42:08 am
content: Quote from: ataradov on October 13, 2013, 12:41:01 amin order to win?can you explain that?

author: Dave
author_rank: Super Contributor
timestamp: October 13, 2013, 01:10:15 am
content: This.Quote from: zorkwan on October 10, 2013, 10:53:11 pmNice try.

author: hedgewallace
author_rank: Contributor
timestamp: October 13, 2013, 02:30:37 am
content: QuoteIt is mainly to prevent people from spamming the forums with pointless posts.There are people out there that really want the prizes, and they put in lots of effort writing decent posts.If Dave thinks that the winners posts don't match the criteria, than he may have a redraw.QuoteDave stated this in the first post in the contest. He also stated this on the YouTube video announcing the competition.
Nichicon UCZ question - Page 1
Forum section: electronics / beginners

author: taste_tester
author_rank: Regular Contributor
timestamp: May 29, 2022, 01:20:08 am
content: When looking for surface mount capacitors with a high ripple current, I came across Nichicon UCZ. But I don't understand on the datasheet, UCZ is described as "Chip Type, High Reliability. Low temperature ESR specification."What is Chip Type? I guessed it's for use with microcontrollers and other IC's, but don't really understand why to choose this series of capacitors.I'm buying capacitors to repair a very heavily used (abused?) china made JBC clone, which has some difficulty with power-on recently. I frequently start and stop the iron so I thought maybe frequent power transients are wearing out whatever capacitors are inside. I'm waiting for a spare iron to arrive in the mail before I take this apart to diagnose it.I already found this unit (Best BST-933B) has 3x 470uf 25v, 2x 220uf 16v, 4x 10uf 35v, 1x 22uf 35v

author: Martian Tech
author_rank: Regular Contributor
timestamp: May 29, 2022, 03:01:30 am
content: Chip Type means it's a surface mount device and doesn't have leads (which appears to be what you want).
Nickel strips & AA NIMH ampacity? - Page 1
Forum section: electronics / beginners

author: GerGa
author_rank: Contributor
timestamp: December 08, 2024, 10:35:27 pm
content: Hello,I am replacing the AA NIMH cells in a Hotronic ski boot heater.I want to use Tenergy flat top AA NIMH batterys.https://power.tenergy.com/tenergy-aa-2000mah-nimh-flat-top-rechargeable-battery/?gad_source=1&gclid=Cj0KCQiApNW6BhD5ARIsACmEbkUyff2aXzB_H6VGTd-OJDmU1k4rXBKhZWTJMBxiM_QIdG20eTOIvpYaAn-2EALw_wcBThe old pack had .2x4mm nickel strips, and I don't want to spend a fortune on a spot welder, while the cheaper spot welders don't have the power for 0.2mm strips.I'm wondering if 0.1x4mm strips will work but no idea:A: how to calculate nickel strips ampacityB: how much current my battery pack will be capable of. Cells are 1.2v, 2000mah, pack is 4 in series, so 4.8V, 2000mah. In the link to Tenergy, the cell reads "standard discharge: 380mah to 1.0V. Not sure that means anything for this.Any help on this problem?Thanks

author: BeBuLamar
author_rank: Super Contributor
timestamp: December 08, 2024, 10:52:34 pm
content: The maximum current a battery cell can deliver depends on its voltage (which you know) and its internal resistance (which Tenergy doesn't list). Since NiMH battery has low internal resistance its maximum current is quite high. But for the device that you use it with how much current would that device draw? It may not be a lot.

author: GerGa
author_rank: Contributor
timestamp: December 10, 2024, 08:57:46 pm
content: Quote from: BeBuLamar on December 08, 2024, 10:52:34 pmThanks for the reply.I received the datasheet for the Tenergy battery.It reads:Internal resistance (IEC61951-2 (2017) 7.10.1)Within 1 hour after being standard charged, the internal resistance is not greater than 38mΩ, as tested by 1000Hz AC source.

author: IanB
author_rank: Super Contributor
timestamp: December 10, 2024, 09:07:42 pm
content: You can probably find some tests online for the high current performance of AA cells. It depends a lot on the design and quality of the cell, but most good quality AA cells should manage 5 A comfortably, and some can get up to 10 A. But at that discharge rate the cells are quite stressed and will also get warm. Consumer products are unlikely to run to such high discharge rates, since if you did run a 2000 mAh cell at 5 A discharge it would barely last for 20 minutes. Not very useful if you want to wear the ski boots for a few hours.Your best estimate would be to divide the battery capacity by the run time and use that to estimate the current draw. And I imagine the thinner nickel strips would be fine.

author: thm_w
author_rank: Super Contributor
timestamp: December 10, 2024, 10:56:52 pm
content: You can see some data here:https://envodrive.com/blogs/articles/lithium-ion-battery-pack-how-is-it-madeIf its 380mA discharge then thats fine.

author: GerGa
author_rank: Contributor
timestamp: December 10, 2024, 11:29:44 pm
content: The simple Ah divided by hours..the heater specifies it will last 2.5 to 4 hours at the hottest setting.2Ah/2.5 = only 0.8amps
Nifty tools (ideally open source) - logic simplification BASED ON STOCK! - Page 1
Forum section: electronics / beginners

author: py-bb
author_rank: Regular Contributor
timestamp: August 25, 2023, 01:39:12 am
content: By "based on stock" I mean for example I have a TONNE of 74'00s, it's weird.I was looking for a quick tool online or something to simplify logic expressions and I really couldn't find much,http://www.32x8.comthis was quite handy....I would have even settled for like a wiki or "catalogue" style page, "here's X made in a variety of different ways" (eg for a mux or XOR gate)If I can't find anything I'll dig out some textbooks and write something(I've got experience from writing compiler optimisations)BUT I'd very much like the reader to post whatever he or she thinks might even be remotely relevantso I can take a look at least at the interface and whatnot and reinvent as little of the wheel as possible.Cheers

author: Ian.M
author_rank: Super Contributor
timestamp: August 25, 2023, 02:22:57 am
content: That was one of the things Logic Friday could more or less do (based on type of gate and number of inputs rather than by IC p/n). Seehttps://www.eevblog.com/forum/projects/74-series-logic-design-equation-optimiser/Seehttps://www.eevblog.com/forum/beginners/line-follower-and-logic-gates-simplification/for an example of using it.Also seehttps://en.wikipedia.org/wiki/Espresso_heuristic_logic_minimizer
Nintendo Gameboy Advance Micro and Sp - In need of schematic circuit diagram - Page 1
Forum section: electronics / beginners

author: recyclednews
author_rank: Newbie
timestamp: May 10, 2014, 12:27:45 am
content: Hi,Thank you for taking the time to read this. I have spent 3 days looking online and I can not find anything. I have 2 Gameboy micros that have short circuits. I am having an extremely hard time figuring out where they are. If I maybe had the circuit diagram that shows the components and current flow. I could determine what is failing and replace it. If you can please help and if I posted this on the wrong location I apologize... Just tell me where to post it.Thanks in advance.

author: Skimask
author_rank: Super Contributor
timestamp: May 10, 2014, 02:46:52 am
content: Quote from: recyclednews on May 10, 2014, 12:27:45 amIf you're so sure the GB's have "short circuits", cut the circuit boards in half and reconnect them with 1 meter long wires.That way the circuits will be much longer.

author: rexxar
author_rank: Frequent Contributor
timestamp: May 10, 2014, 02:57:28 am
content: IIRC, Gameboys have a couple SMD fuses. You may want to check those, but if they're blown, that indicates a bigger problem downstream. Most likely one of the ICs has developed an internal short.I doubt very seriously that there's schematics for any modern Nintendo products. On the GBA they covered the entire circuit board with silkscreen to "prevent" reverse engineering, so it's not likely they released schematics.