hybridfree/eevblog-posts huggingface dataset:
microcontrolller short circuit?!! - Page 1
Forum section: electronics / beginners

author: poohpary
author_rank: Contributor
timestamp: August 17, 2013, 06:09:59 am
content: hi...i use an atmega32 in my pcb board..my circuit was fine but i dont know what happened that after turning on the supply for (the last time) micro got so hot . with a multimeter in diode check mode it seems tracks of +Vcc and GND are connected (no power is applied to circuit)...and it seems 3 pads of micro that were programed to be input (i have not used them) are connected to Vcc or GND.so i dont know whats wrong...with micro getting hot can i say that short circuit is done inside of micro? and how can i be sure nothing is wrong with my pcb board so the problem will be solved by exchanging micro?is there any body to help me plz?!

author: David_AVD
author_rank: Super Contributor
timestamp: August 17, 2013, 06:31:25 am
content: Is there a chance you applied too much voltage or reversed the polarity - even for a split second?

author: poohpary
author_rank: Contributor
timestamp: August 17, 2013, 06:33:49 am
content: no...not reverse not too much...i am sure...(thanks for your reply )

author: tiborsimon
author_rank: Contributor
timestamp: August 17, 2013, 06:34:51 am
content: I would check the pcb, and the soldering again. If everything is fine, it could be a latchup..

author: David_AVD
author_rank: Super Contributor
timestamp: August 17, 2013, 06:35:23 am
content: Maybe a quick picture of the PCB and setup would help.

author: poohpary
author_rank: Contributor
timestamp: August 17, 2013, 06:44:21 am
content: its kinda complicated...i have 6 different voltage supply in my circuit...but the problem is with +5V and the GND...pcb picture would not help cause it needs a lot of explanation

author: David_AVD
author_rank: Super Contributor
timestamp: August 17, 2013, 06:47:55 am
content: All the more reason to explain it in that case. It quite possibly has a bearing on what caused the issue.
Microlab Solo 9c Tweeter noise - Page 1
Forum section: electronics / beginners

author: Audiomachine
author_rank: Newbie
timestamp: March 10, 2024, 10:12:10 pm
content: Dear audio enthusiasts,I am having since a long time a noise coming out from my Tweeter speaker of a model Microlab Solo 9C.I would describe it as a low wind, but it's hearable from a 3m distance, when the speakers are just powered on. The noise is coming from the main "right" unit, where the mothear board is, even when the left speaker is unplugged with audio input.I have tested it with different power outlets 230V/50Hz.The noise is not present after turning on the speakers. It starts to be audible after a few minutes. I assume, it has something to do with the transformer as it heats up?Could someone of you identify what could be the cause and how to possible get rid of it?It really bothers my when I don't listen to music and I have to turn off the speakers all the time.Sample recording:https://voca.ro/1iFQM1x8LmYKThank you for any kind of constructive feedback.
Micron Technology Component Identification - Page 1
Forum section: electronics / beginners

author: yoda_bear
author_rank: Contributor
timestamp: May 12, 2017, 09:20:55 pm
content: I am having some trouble determining the part number to search here. Can anyone tell me if I have RAM or Flash and how to find some datasheets?

author: yoda_bear
author_rank: Contributor
timestamp: May 12, 2017, 09:25:27 pm
content: The other components I am looking for.

author: chicken
author_rank: Frequent Contributor
timestamp: May 12, 2017, 09:33:54 pm
content: https://www.micron.com/support/tools-and-utilities/fbga?fbga=nw229says part number is: MT29F8G16ADADAH4-IT:D
microphone switching  - Page 1
Forum section: electronics / beginners

author: Flump
author_rank: Frequent Contributor
timestamp: September 18, 2013, 08:44:24 pm
content: i have two ham radio trancievers and want to use one microphonefor both of them so i need to make a switch up to switch thewires from the mic to one or the other radio but not both at the same time.radio ascreenaudiotxrxradio bscreenaudiotxon "radio a" rx and screen need to be linked in recieve modeor there is no speaker audio, this is normally done with apush to talk switch in the microphone.the mic i am going to use has a ptt switch that does rx/screen switchingso that is fine if the selector switch is set for the mic to go to "radio a"but i would like that radio to also recieve when the mic is switched to "radio b"been trying to workout a way of doing all this at the same time and not reallygetting anywherecan anyone sugest any ideas for this ?

author: David_AVD
author_rank: Super Contributor
timestamp: September 18, 2013, 08:51:37 pm
content: Do you want "radio a" to be in receive mode, even when "radio b" is transmitting (and visa versa) ?

author: Flump
author_rank: Frequent Contributor
timestamp: September 18, 2013, 08:57:37 pm
content: yes David i dothey are on different bands which i monitor at the same time

author: David_AVD
author_rank: Super Contributor
timestamp: September 18, 2013, 09:23:52 pm
content: You should be able do that with either a multi-pole switch or some relays.Arrange it so the Rx contact for "radio a" is shorted to the screen when the selector switch is in the "radio b" position and visa versa.The switching for the tx and mic wiring will be straightforward.

author: Flump
author_rank: Frequent Contributor
timestamp: September 18, 2013, 11:09:55 pm
content: how about one of thesehttp://www.ebay.co.uk/itm/5V-8-Channel-Electronic-Relay-Module-for-Arduino-PIC-PLC-AVR-MCU-DSP-ARM-/290915538588?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item43bbead69cwires from mic go to center of four of the relays (tx rx audio screen)then NO and NC goes to the 2 different radios,so no voltage on relay coils = radio avoltage on coils = radio band 4 spare relays means i can add up to 2 more radios later on.will this work ?

author: David_AVD
author_rank: Super Contributor
timestamp: September 18, 2013, 11:15:38 pm
content: You'll also need to arrange for the shorting of rx to screen on the radio that's not selected.
Microscope for SMD soldering and visual impairment - Page 1
Forum section: electronics / beginners

author: rgawron
author_rank: Contributor
timestamp: October 29, 2015, 12:16:18 am
content: Hello,let's say that I have visual impairment X dioptre on left Y dioptre on right (X != Y), both around four (I see correctly on small distances). I would like to buy a binocular microscope (as mentioned in the title) and be able to use itwithoutmy glasses. Is it possible? If yes, what kind of additional factors should I consider before buying the microscope?Thanks.

author: tggzzz
author_rank: Super Contributor
timestamp: October 29, 2015, 12:29:33 am
content: I don't have a visual impairment other than +2.5D reading glasses. Nonetheless I find it difficult to use microscopes, especially stereo microscopes. (My stereo vision is just fine; I've been taking stereoscopic photos for the past 30 years).I suspect you will find it difficult to get a solid answer that is relevant to your condition.Have you tried things likewww.maplin.co.uk/p/rolson-2-led-12x-18x-25x-and-35x-magnifying-visor-n70fk(which are easily available on ebay). There are four strength magnification lenses; I use either of the middle two depending on what I'm doing. Two lenses can be put "in series" for extra magnification, or I would imagine to get different strength for each eye.The visors have the advantage that they are cheap and easy to try and modify.

author: ConKbot
author_rank: Super Contributor
timestamp: October 29, 2015, 01:13:17 am
content: Youre near sighted, so you should be in luck, I'm nearsighted (I forget how bad, but it aint good, 12 point font at around a foot away to be pretty clear). Ive had luck using stereo microscopes both with and without glasses (much more convenient with glasses on, when you have to do stuff thats not under the microscope) I'm not sure about if youre far sighted, so I cant say either way on that. Make sure the microscope has either a diopter adjustment on one eye piece, or at least set-screws to hold the eye pieces in place, you can tweak the position of the eye piece slightly and use the set screw to hold it so they both are in focus. The twist diopter adjustment is obviously preferred. If it has neither, and the eye pieces just drop into place, you could always shim one.

author: electronupdate
author_rank: Regular Contributor
timestamp: October 29, 2015, 02:51:21 am
content: Quote from: rgawron on October 29, 2015, 12:16:18 amFor the differences between your eyes look for a Stereo microscope which has a "Diopter Adjustment".... it allows each eye piece to be set to a different magnification
Microsoldering help - Page 1
Forum section: electronics / beginners

author: joshm101
author_rank: Newbie
timestamp: December 25, 2023, 02:11:09 am
content: Hey I have been working for myself fixing electronics. (Phones, iPads) etc.. But I want to dive deeper and learn the board level repairs for these devices.I am buying a Sugon T26D Soldering Station but I want to use the JBC 210, 245 and NT115 Nano Handles with the JBC Tips.I would like to know if the Genuine JBC Handles can fit this model of Soldering Station? I tried google but I was getting mixed answers and I couldn't find much information.Any help would be much appreciated, thanks.

author: Dan123456
author_rank: Regular Contributor
timestamp: December 25, 2023, 03:33:17 am
content: Hi and welcomeUnfortunately, I am no help to youWith that said, there are heaps of amazing people here so am sure someone here will be able to help or point you in the right directionMerry Christmas and I look forward to seeing you around

author: Wind Tse
author_rank: Newbie
timestamp: December 27, 2023, 07:17:50 am
content: Trying to help.You may figure out these question so you can find the answer yourself.1. If the plug matches?2. If the Watts matches?3. Pay attention to the temp.

author: uli12us
author_rank: Contributor
timestamp: January 12, 2024, 10:55:42 am
content: I have bought 1 year ago an aifen A9, this station can work with all the JBC parts you need. beyond that you can use the C470, but with reduced power because the station only have 120W power. Now you can buy the station in a 2023 version with up/down buttons on the soldering iron, that works like the 2 up/down buttons on the station. And the Holder for it is changeable in the angle. The only disadvantage I found is, with the K insert, you can't use the extractor because the peak is to long for it. I have extended the fork for 1cm, 0,4"

author: liaifat85
author_rank: Regular Contributor
timestamp: January 12, 2024, 02:43:22 pm
content: You can find this video series helpful:https://www.youtube.com/playlist?list=PL4INaL5vWobD_CltiZXr7K46oJ33KvwBt
Microtek 3KVa inverter - Page 1
Forum section: electronics / beginners

author: Mlungu
author_rank: Newbie
timestamp: September 15, 2019, 10:20:58 am
content: I'm looking for a circuit diagram for a Microtek Soho 3KVa inverter. They were made in India around 2007. I need the diagrams for both the main and secondary boards.
Microtest Microscanner remote wiremap - Page 1
Forum section: electronics / beginners

author: EmperiuM
author_rank: Newbie
timestamp: October 19, 2022, 03:57:23 pm
content: Hello, I'm new here and I'm an IT professional from Portugal that doesn't understand much about electronics.But I have this issue that I can´t solve by myself.In my work I need to check utp cables (rj45) many times and I have 2 network testers from Microtest Microscanner (pre-Fluke) the model is TWP (p/n: 2947-4000-01) just like this one I found onebay. my problem is that someone here lost the 2 remote wiremaps adapter a long time ago.that been said, I bought from aliexpress 2 wiremaps adapter, some chineses clones so I hought.This equipment, as some of you might know, have more than one function/modes:Cable Lenght - That is workingSignal Tone - That is also workingOffice - Is also but both the remotes got Office 9Wiremap - the most important to me, not workingthe remote that I bought was this oneI'm tempted to tear it appart to make it work, but I don't know how to and I'm also been searching the web for some blueprints from the original but haven't got any luck so far.Can someone from here can help me ?Thank you very much.img from the original bundle
Microwave oven linear transformer - Primary and secondary winding - Page 1
Forum section: electronics / beginners

author: bitluni
author_rank: Contributor
timestamp: October 18, 2013, 03:15:14 pm
content: I have seen so many people on youtube which take the huge linear transformer and exchange the secondary winding by a thick wire to get high amps.My question is:Does it really matter which is the primary and secondary? Or can I just connect the secondary to mains and get lower volts on the former primary coil?I know, I have to consider maybe the higher resistance of the thinner wire, but from my understanding it really shouldn't matter so I could use this chunky transformerswithout modification to get lower voltage and high amps just by connecting it different way around.I didn't had the luck to get my hands on one of these yet so I wasn't able to do any experiments

author: Kremmen
author_rank: Super Contributor
timestamp: October 18, 2013, 05:13:43 pm
content: Quote from: bitluni on October 18, 2013, 03:15:14 pmYes, it really does matter.QuoteDon't try it. You might live but the results won't be any good.Quote2nd time: it does matter. The induction in the core will be all wrong if you excite it with the secondary winding whose number of turns is so at variance with the true primary. There is more than just the turns ratio to consider, you see. There is the mag circuit that actually transfers the energy between coils and the setpoint of flux in the core should be roughly what was originally designed. Also, the microwave transformers are gapped core so their loss behavior and other parameters are far from ideal.QuoteDo it like the others do: chisel out the secondary and wind your own. That way the mag circuit at least works the way it was supposed to.

author: Zero999
author_rank: Super Contributor
timestamp: October 18, 2013, 05:26:45 pm
content: You could theoretically connect the mains to the secondary to get a much lower voltage but you'll only get a tiny fraction of the design power out. The biggest problem with this is the secondary is bonded to the transformer core at one end so it's a very dangerous thing to do.

author: bitluni
author_rank: Contributor
timestamp: October 18, 2013, 05:51:36 pm
content: Quote from: Hero999 on October 18, 2013, 05:26:45 pmThis was the missing piece in the puzzle.Thanks for the replies!
micsig DP10013 input voltage - Page 1
Forum section: electronics / beginners

author: thedoc298
author_rank: Contributor
timestamp: August 12, 2023, 06:30:34 pm
content: The specs for the DP10013 areMaximum differential test voltage (DC+ACPK-PK): 130V (50X), 1300V (500X) from their siteSo does that mean 130 volts Pk to Pk or 65 volts Pk which in turn would be 46 volts rms so on x50 we have 46 volts rms maxsame 1300 PK to PK = 650 Pk or roughly 460 volts rms so on x500 input is 460 volts rms maxSo why don't they state it like that...? Or am I all screwed up..?

author: m k
author_rank: Super Contributor
timestamp: August 24, 2023, 12:48:02 pm
content: It's differential so potential difference.Forget grounds and signal shapes.
Micsig TO1104 Help - Page 1
Forum section: electronics / beginners

author: ServiceXp
author_rank: Contributor
timestamp: December 09, 2018, 10:57:02 pm
content: I have 2 questions about how to properly use this scope with an AC/DC Amp Clamp.I'm trying to figure out how to use an amp clamp (This Onehttps://www.amazon.com/gp/product/B00QK2QNKS/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1) with the scope in a way I don't have to do any manual math.The clamp is set to 1mV/100mA - The probe type is set to 100x and Current. The problem is I can't reconcile the RMS amperage with the wave form amperage with the actual (taken using a Fluke 30 Clamp Meter).1) Actual ~5.5 amps Fluke2) RMS in screenshot is 6.43A3) Waveform set to 5A/Div4) Same 'error' using 1mV/10mA1) Question: what am I doing wrong?2) Screenshot 2: Why do the level controls disappear with anything over 100ms?

author: ServiceXp
author_rank: Contributor
timestamp: December 11, 2018, 12:41:12 am
content: went another round with it today and still no luck. I'm sure I missing something fundamental..

author: StillTrying
author_rank: Super Contributor
timestamp: December 11, 2018, 11:55:07 am
content: All I can think of is to apply a 100mVpppuresine wave to the Fluke and TO1104 at the same time, and compare the RMS values.

author: ServiceXp
author_rank: Contributor
timestamp: December 11, 2018, 10:18:37 pm
content: Thanks StillTrying. I borrowed a much better True RMS Fluke Amp Meter and have discovered the RMS reading on the scope matches that of the borrowed Fluke, within ~10mv. The waveform, if I'm reading it correctly (5v/Div) is still not representative of actual.

author: Micsig_support
author_rank: Regular Contributor
timestamp: December 12, 2018, 06:04:31 am
content: Hello Question 1,There is no problem for probe setting, can you increase the time base to see at least 4 periods waveform in the screen to see it?question 2， when time base is over than 100ms, the Roll mode is turned on automatically, pls go to Dispaly-Roll-Disable. then you will see the trigger level.

author: ServiceXp
author_rank: Contributor
timestamp: December 12, 2018, 12:40:20 pm
content: Thank You Micsig Support.Q1) Added the requested screenshot.Q2) Perfect, Thank You.

author: ServiceXp
author_rank: Contributor
timestamp: December 17, 2018, 03:51:53 pm
content: Any word on this @Micsig_support ??
Micsig TO1104 automotive reference waveform ? - Page 1
Forum section: electronics / beginners

author: gurusonwheels
author_rank: Newbie
timestamp: April 14, 2019, 11:10:03 am
content: I have a TO1104 i just purchased .Does anyone have a package of Wavform ref files for automotive that they would share ?would love to have them .

author: exe
author_rank: Unknown
timestamp: April 14, 2019, 07:34:04 pm
content: I wonder what this feature actually does.
MID 3D - Page 1
Forum section: electronics / beginners

author: Isaac Newton
author_rank: Contributor
timestamp: December 10, 2012, 10:51:48 pm
content: So, I was looking for a pcb manufacturer here in Brasil and one of them says they are capable of doing MID 3D. Well, what is, exactly, MID 3D? What softweare do they use to engeneere the parts?

author: free_electron
author_rank: Super Contributor
timestamp: December 11, 2012, 01:10:14 am
content: Molded interconnects. Basically putting pieces of copper in plstic to create custom interconnects. typically used for things like car taillights etc...such things are typically designed using Catia CBD
Middlebrook's Method VS Tian's Method VS Middlebrook's General Feedback Theorem - Page 1
Forum section: electronics / beginners

author: promach
author_rank: Frequent Contributor
timestamp: June 13, 2020, 05:51:35 pm
content: Forhttps://sites.google.com/site/frankwiedmann/loopgain, how isTian's Methoddifferent compared toMiddlebrook's MethodandMiddlebrook's General Feedback Theorem?Tian's MethodMiddlebrook's MethodMiddlebrook GFT Theorem

author: promach
author_rank: Frequent Contributor
timestamp: July 11, 2020, 11:47:08 am
content: I have two questions with regards to the two picture screenshots below:1. WhyChain Theorem (CT) does not have Tn as in N-EET?2. Inside the second picture below, why the circled expression "must be the gain when Z = 0" onpage 39 of this document?
Migsic MS210T software for Windows 10 - Page 1
Forum section: electronics / beginners

author: Electronicstarter2024
author_rank: Newbie
timestamp: October 20, 2024, 07:41:39 am
content: Good day,I have a question regarding an oscilloscope, specifically the Migsic MS210T. This is an older model, and possibly because of that, I am unable to find the corresponding software or drivers for the PC. I have already contacted the supplier, Migsic, but the file they provided lacks some necessary drivers and is only compatible with Windows 7. Despite my efforts to get the software running, I have been unsuccessful.Does anyone have experience visualizing the Migsic MS series on Windows 10? And does anyone have the original software that I could try to install? Migsic has stated that they now have a new product line and no longer offer support for the older models.Thank you in advance for your help.Kind regards,Jeroen

author: Solder_Junkie
author_rank: Frequent Contributor
timestamp: October 20, 2024, 11:30:42 am
content: You can run an old operating system as a virtual machine, including USB and RS232 connections. Provided you have a Windows 7 install disk, you can install Windows 7 under Virtual Box by Oracle.https://www.virtualbox.org/I have used Windows XP in a virtual box to run legacy battery analyser hardware/software that connected via USB.Virtual Box is free, as is the extension pack add-on.SJ

author: Electronicstarter2024
author_rank: Newbie
timestamp: October 20, 2024, 08:45:45 pm
content: Thanks for the reaction, I have installed everything. Windows 7 virtually installed and working well. Unfortunately the software does not work. The installation cannot be completed correctly. If anyone has any tips, ideas or suggestions, I would love to hear them.

author: coromonadalix
author_rank: Super Contributor
timestamp: October 20, 2024, 08:59:26 pm
content: would be nice to share a download link to be surei have installed oscilloscope pc software v 1.0.7 with no problems on win 11 x64 and the related visa driversis this the one you talk ?

author: Electronicstarter2024
author_rank: Newbie
timestamp: October 20, 2024, 09:09:16 pm
content: Good day, I received the software directly from Micsig as I couldn't find it available for download anywhere. The file was sent via WeTransfer, but I believe it may be incomplete. Could you possibly resend the software or indicate where I can download the files so I can verify if it works correctly? Thank you in advance for your time and effort.Jeroen

author: Electronicstarter2024
author_rank: Newbie
timestamp: October 29, 2024, 04:49:10 pm
content: "After a few days of installing and trying different Windows versions, it finally works. Migsic acquired new software and discovered through the manual that the system needed to run on a 32-bit version of Windows. This was the reason why the installation had previously failed."
Mikroc pro keypad library proteus error - Page 1
Forum section: electronics / beginners

author: khatus
author_rank: Regular Contributor
timestamp: July 21, 2021, 08:10:00 am
content: Quote from: khatus post_id=311224 time=1626793245 user_id=48839

author: Renate
author_rank: Super Contributor
timestamp: July 22, 2021, 11:35:55 am
content: With the Hitachi protocol LCDs you are supposed to check the busy flag before doing any writes.That should be done in your LCD library.Maybe your library doesn't do that correctly, maybe your simulator doesn't handle the busy flag correctly.Why don't you just try it with real hardware?I don't like your ascii_to_int()First of all, it's really int_to_ascii or even scancode_to_keycode.You don't need a break if you have return.You don't need to set pulsador just to return it, return 55.You shouldn't use ASCII numeric values when a char is clearer, return '7'.A lookup table is shorter, more efficient and clearer:Code:const char keys={'7', 8', '9', '/', '4', '5', '6', '*', '1', '2', '3', '-', 'C', '0', '=', '+'};Edit: I forgot 7.
Mileseey tr256i compatibility with the raspberrypi? - Page 1
Forum section: electronics / beginners

author: NapoleonJones
author_rank: Newbie
timestamp: January 24, 2024, 10:23:10 am
content: I have a school project about a thermal camera that detects pest with the use of AI (YOLOv5). The MLX90640 and the AMG 8833's resolutions are not enough for the project. We plan to buy a Type C OTG Thermal Cam like FLIR and SEEK because there are videos on YouTube that shows there compatible with the Pi. However, they're not available in our country and may not arrive in time for us to use so we opt with the Mileseey TR256i. Would it work if we connect it to the raspberry Pi via a reverse OTG cable?Side note :A person from a different forum said that it would work given that it is compatible with android but we need to put some fair bit of python coding. What python coding or programming would he mean by that??Thank you for your answers and advices.
Mill PCB partially through? - Page 1
Forum section: electronics / beginners

author: shai
author_rank: Contributor
timestamp: April 14, 2019, 05:33:43 am
content: I'm trying to make automatic feeders for PNP using two PCBs as the "walls" of the feeder. I was thinking it would be great to mill into the PCB walls partially to guide the SMT tape. Is it possible to export gerbers and upload to a service like JLCPCB.com so they can automatically mill a certain depth rather than milling all the way through?I know I can probably get a CNC and do it myself, but was wondering if a service provider can be directed to do it somehow? See attached examples of countersunk PCBs I found online.

author: shai
author_rank: Contributor
timestamp: April 14, 2019, 06:14:27 pm
content: Anyone?

author: pwlps
author_rank: Frequent Contributor
timestamp: April 14, 2019, 06:50:15 pm
content: They are definitely able to do that: for blind vias pcb manufacturers often prefer control depth drilling than multiple lamination cycles because it is cheaper. How to code it for a general shape is a different issue.

author: shai
author_rank: Contributor
timestamp: April 14, 2019, 07:08:06 pm
content: So is there a way to do this in Eagle where you tell the PCB manufacturer to do controlled depth milling? or countersunk screws?

author: PartialDischarge
author_rank: Super Contributor
timestamp: April 14, 2019, 07:21:20 pm
content: PCBWay does it. Its called Z milling, but don't know how to specify depth, I guess the area to be milled is just another layer. If you ask them let us know

author: pwlps
author_rank: Frequent Contributor
timestamp: April 14, 2019, 07:43:45 pm
content: Quote from: shai on April 14, 2019, 07:08:06 pmFound a similar question on stackexchange:https://electronics.stackexchange.com/questions/312753/is-there-a-way-to-make-a-drill-hole-only-up-to-half-depth-of-the-pcb-in-eagle
Miller Capacitance ?? - Page 1
Forum section: electronics / beginners

author: shanecy
author_rank: Contributor
timestamp: July 17, 2013, 08:08:14 pm
content: What is the miller capacitance?

author: Bored@Work
author_rank: Super Contributor
timestamp: July 17, 2013, 08:25:52 pm
content: Thanks for informing us that google is currently broken.

author: andyturk
author_rank: Frequent Contributor
timestamp: July 17, 2013, 08:32:56 pm
content: Quote from: Bored@Work on July 17, 2013, 08:25:52 pm

author: Smokey
author_rank: Super Contributor
timestamp: July 17, 2013, 08:49:52 pm
content: Google is broken!!!?!?!?!? OMG can you even imagine. That would ruin my day.The wiki article on the miller effect looks like it could use some more info actually.http://en.wikipedia.org/wiki/Miller_effect

author: andyturk
author_rank: Frequent Contributor
timestamp: July 17, 2013, 09:13:09 pm
content: Quote from: Smokey on July 17, 2013, 08:49:52 pmIn truth, big G seems to be fine. But Digikey is *definitely* down.

author: Smokey
author_rank: Super Contributor
timestamp: July 17, 2013, 09:39:15 pm
content: Quote from: andyturk on July 17, 2013, 09:13:09 pmThat's almost as bad as google being down! Digikey is fine here.

author: andyturk
author_rank: Frequent Contributor
timestamp: July 17, 2013, 09:57:23 pm
content: Quote from: Smokey on July 17, 2013, 09:39:15 pmSeems to be back now. I'm glad it didn't lose the stuff in my current order. Phew!
milliOhm meter vs Impeadence analyzer - Page 1
Forum section: electronics / beginners

author: R005T3r
author_rank: Frequent Contributor
timestamp: December 22, 2016, 10:19:13 am
content: So,Recently, I've been interested about milli-Ohm meters, because simply put: DMMs are not able to measure resistance accurately down to the milli/micro ohm range. The bad news is that low ohm values are really susceptible at temperature changes because when things warm up, they increase the resistance, and if you get a decent gear in a properly set up, it will compensate the result value for precision testing.The point is, I don't understand if milliOhm meters can be replaced with Impeadence analyzer: I know, they surely can measure DC resistance, down to the micro Ohm range, and they can also compensate the temperature. So, what's the deal with having a MilliOhm meter, compared to an Impeadence analyzer (beside, the fact that Impeadence analyzers can measure other parameters?)? What I'm missing?Apparently, also, the test current is much lower with milliOhm meters, and this will prevent the resistance to change.

author: Gyro
author_rank: Super Contributor
timestamp: December 22, 2016, 10:39:42 am
content: Ok, I'll have a stab...1. Cost. A DC milliometer (or microohmeter) will be a lot cheaper than a full blown impedance analyser.2. An impedance analyser will measure inductive component as well as resistance. I'm not sure, but I suspect that it will have difficulty in resolving the two (Inductance will probably dominate), which may not be what you want for DC situations.3. It is sometimes helpful to measure at higher current as it is more representative of actual operation. ie. if the resistance is going to go up at operating current then it's definitely something you want to know about.QuoteOn the contrary, many milliohmmeters are designed to be able to putsignificantcurrent through the test item, I don't think many impedance analysers do this.Better quality milliohmmeters cancel thermocouple effects by reversing the test current, pulsing the test current, subtracting thermal emfs between current applications etc.
Milwaukee M12 Cordless drill repair - Page 1
Forum section: electronics / beginners

author: Arkadius1984
author_rank: Newbie
timestamp: November 27, 2017, 07:17:32 pm
content: Hi all,My name is Ark, and I live in the UK.I'm troubleshooting (or actually struggle with) my milwaukee m12 brushless drill - the component shown on the photo is a diode ( most likely schottky one, as voltage drop across it is only 0.34v) - however I can't find any information online as to it's specs - it has got marking as shown on the photo - I would really appreciate any help with identification. Also that diode is connected straight to the +12v supply as shown, but on it's cathode it only shows around 9.6v after battery is connected to the circuit - any ideas?

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: November 27, 2017, 07:56:07 pm
content: W37 might actually be W3Z for a W3 Zener diode.http://www.s-manuals.com/pdf/datasheet/b/z/bzt52c2v0-bzt52c51_r37-2_diodes.pdfPage 2 item 5 »BZT52C3V3«Just a wild guess though

author: Arkadius1984
author_rank: Newbie
timestamp: November 27, 2017, 08:58:03 pm
content: I was thinking the same - however that 0.35v drop doesn't fit:D unless there are zeners with lower than 0.6-0.7v drop:) even if it is zener, there is still a question of choosing the one with right specs:D

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: November 27, 2017, 09:22:01 pm
content: Would 9.6V be the correct for the circuit? Maybe it is a Zener that should regulate/stabilize at 3.3V but since it is damaged, forward voltage drop is no longer 0.7V and Uz changed to 9.6V - quite odd since I would expect a Zener to be either fried or working correctly...

author: Arkadius1984
author_rank: Newbie
timestamp: November 27, 2017, 09:54:47 pm
content: I forgot to add that I've borrowed a similar drill from my mate, and comparing the voltages, the zener's cathode on his pcb is 11.6V in opposition to my 9.6v. It's really damn hard to troubleshoot electronics without a schematic - especially for someone like me who is a complete beginner
Mimetics Corp. Amigen Repair - Page 1
Forum section: electronics / beginners

author: The Eight-Bit Link
author_rank: Newbie
timestamp: May 02, 2015, 02:30:14 am
content: Hey all,I've got an Amiga Amigen genlocker that doesn't output a good picture, especially when there is an input signal. Not sure where to begin, but it does have tantalum caps, so I may replace them. Any other suggestions or points of focus?
Mimicking a cluster (car dash) circuit to allow for fuel measurement.  - Page 1
Forum section: electronics / beginners

author: zoloft_
author_rank: Newbie
timestamp: December 05, 2019, 11:55:40 pm
content: Hi,In an effort to convert my car's cluster to an arduino controlled system I have run into a problem reverse engineering the fuel level circuit. On first glance it seems to be a simple series? circuit that measures the voltage drop across the fuel sensor to get the data, however when the circuit is probed, pin 5 (highlighted in green) is connected to ground while pin 6 (highlighted in red) reads a voltage between 1 and 8 volts. The fuel level is read by the PCM by connection at two points (highlighted in blue). If a voltage between 1-8 volts is applied to pin 6 (with the cluster disconnected) the fuel level read by the control module can be manipulated and is directly correlated to the voltage applied. Is there any way I could bypass the cluster to allow for the PCM to read the data in its absence? Perhaps I am likely misinterpreting the circuit as I am new to electrical work. Thanks for the help and any additional wiring diagrams or measurements will be provided as soon as requested.Lily
Min capacitance equation for swithcing reg contains both L and uH?  - Page 1
Forum section: electronics / beginners

author: Starlord
author_rank: Frequent Contributor
timestamp: March 19, 2016, 03:40:59 pm
content: http://www.ti.com/lit/ds/symlink/tps61202.pdfOn page 16, there is an equation:Cout = 5 x L x uF/uHFirst, what the heck is L here? uH is the inductor's inductance. Am I supposed to plug in the inductance twice? Why use two different symbols for the same value in the same equation?Second, what's uF? It's not Cout because Cout is on the left side of the equation there. And same question as above, if it's the same thing, why use two different variables?Maybe Cout is in farads and L is in henries? Why use L instead of H? Because the schematic symbol for an inductor is L perhaps? So L is equivalent to Cout; a label not a unit; and both are specified in whole units?

author: Neilm
author_rank: Super Contributor
timestamp: March 19, 2016, 05:04:49 pm
content: The only thing I can think of is that it is to get the correct units for the capacitance.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 19, 2016, 09:33:05 pm
content: Unit conversion. L is in uH so it has to be divided by a constant of 1uH to get rid of it; then C /is/ in uF so the expression has to be multiplied by 1uF.H/F == ohm^2, so they could've used 1/ohm^2 just as well.More particularly, they could've attached a number to that unit, which you will find is related to either the switching impedance (Vsw(pp) / Isw(pk)) or the source or load (Vin/Iin or Vout/Iout), all of which are at least in the same neighborhood. Seemingly, they assume this is around 1; the 5 sounds like a "magic number", such as ripple% (of the inductor current, or output voltage, or their ratio).Tim

author: bson
author_rank: Unknown
timestamp: March 19, 2016, 09:43:06 pm
content: uF/uH is the unit, not a value. If you multiply uF/uH * uH you get uF.
min Vds for automotive use - Page 1
Forum section: electronics / beginners

author: Simon
author_rank: Unknown
timestamp: November 27, 2010, 02:46:13 pm
content: what would you recommend as the minimum max Vds voltage for a P channel mosfet (so already "floating" at 13V) in an automotive situation ? I'm looking for lowest Ron (1-10 mR range) so I'm left with stuff that is usually no more than 30 V. obviously I can include TVS diodes for protection.

author: qno
author_rank: Frequent Contributor
timestamp: November 27, 2010, 10:08:11 pm
content: usually a P channel fet allows -20V.The higer the On voltage the lower the channel resistance.You can limit the gate voltage with a zener.

author: Simon
author_rank: Unknown
timestamp: November 27, 2010, 11:51:41 pm
content: but the question being will the 30V mosfet survive an automotive environment ? thats from source to drain

author: tyblu
author_rank: Frequent Contributor
timestamp: November 28, 2010, 12:10:14 am
content: Really up to the datasheet and your circuit protection. I'm sure you've heard of a load dump (100V+ for ~0.5s) -- so long as you can buffer your system from an event like that, go for it.

author: Simon
author_rank: Unknown
timestamp: November 28, 2010, 08:53:36 am
content: Well I'd only have room for a few TVS diodes or similar sized protection. most of the time the mosfets will be on so any spikes should pass through them with no ill effect although during start up of the vehicle they will e off so I can't bank on that much

author: Zero999
author_rank: Super Contributor
timestamp: November 28, 2010, 09:44:12 am
content: MOSFETs will be able to withstand avalanche energy without failing.If in doubt, connect a zener across the drain and source terminals.Have you considered N-channel? If it's not going to be turned on continuously you could use bootstrapping.

author: Simon
author_rank: Unknown
timestamp: November 28, 2010, 09:53:26 am
content: yes I'd be putting in protection, TVS from both D and S to ground and yea a 20V zenner from D to S is not a bad idea. The mosfet will be on non stop during normal use, I did think of putting in a circuit to boost the voltage for a drive of a high side N channel fet but really not worth the hassle as I can get P channel 5.4 mR 30V mosfets in SOIC8 packages for £0.4 each

author: Zero999
author_rank: Super Contributor
timestamp: November 28, 2010, 10:03:44 am
content: Quote from: Hero999 on November 28, 2010, 09:44:12 amCorrected.FYI avalanche energy is the power dissipated when the VDSrating is exceeded and the MOSFET conducts when it should be in the off state.
Mini air compressor voltage rating, salvaged from soldering station - Page 1
Forum section: electronics / beginners

author: DarkZero
author_rank: Regular Contributor
timestamp: November 24, 2014, 12:25:17 pm
content: Hi All!Anyone knows on what voltage compressor in the attachment works, i salvaged it from Gordak 952-A soldering station, there was no electronics inside so i couldnt figure it out for my self

author: DTJ
author_rank: Super Contributor
timestamp: November 24, 2014, 01:13:11 pm
content: Same coloured wires - maybe AC?Perhaps try 12VAC then 24VAC and see what happens.Is there any name, part number etc on it?

author: SeanB
author_rank: Super Contributor
timestamp: November 24, 2014, 06:04:33 pm
content: It will be the local mains you have, or what was marked on the label on the case. Inside there will be a coil and a magnet attached to the diaphragm, with some reed valves to direct airflow.Measure the DC resistance of the coil, and see what it is, it will probably be around 300R to 2K, depending on how thin the wire is.

author: DarkZero
author_rank: Regular Contributor
timestamp: November 25, 2014, 08:24:21 am
content: Hey All!i couldnt find any markings either in case it was in or on it, i know whole unit was used on 220v and i found some pictures of the electronics and it seems it is turned on by a small relay still cant figure out if relay was taking power from transformer, which is rated 26VAC it seems, or the grid guess ill have to find some AC source of about 24VAC and give it a go. Also i measured resistance between the wires it reads 420?.

author: rauloliv
author_rank: Contributor
timestamp: November 25, 2014, 09:47:20 am
content: It seems a lot like the ones found on Aoyue stations, they are 24Vac
Mini laptop not powering on. - Page 1
Forum section: electronics / beginners

author: frankk22
author_rank: Newbie
timestamp: December 08, 2023, 04:10:53 pm
content: Good day everyone.I have an issue here with my mini laptop that is bothering me. If anyone can help.I was using a wrong charger 5V instaed of 12V. I got hold of a 12V charger double checked voltage first before puggingin. The battery was almost half full and it was on. AS soon as i connected the charge, the light on the charger went off, i then checked the laptop and fount it ws off. Its not switching on anymore.Is there a chance of it getting fixed.Thanks.

author: JustMeHere
author_rank: Frequent Contributor
timestamp: December 10, 2023, 11:21:19 am
content: Try disconnecting the battey.

author: liaifat85
author_rank: Regular Contributor
timestamp: December 10, 2023, 01:03:24 pm
content: Disconnect the charger, remove the battery if it's removable, and hold down the power button for about 30 seconds. Then reinsert the battery (if applicable) and try to power on the laptop again using the correct charger. Also check if there is a sign of any physical damage like a burnt smell or so on.By the way, you can make your own laptop using Raspberry pi :https://www.theengineeringprojects.com/2022/02/introduction-to-raspberry-pi.htmlYou will find many video tutorials on this topic like this one:
Mini-MELF Diode: - Page 1
Forum section: electronics / beginners

author: Mad Professor
author_rank: Regular Contributor
timestamp: August 14, 2016, 11:24:51 am
content: Hi All.This is the 1st time I have had any dealing with Metal Electrode Leadless Face (MELF) components.I think the component is a Mini-MELF Zener Diode. the only markings is a single blue band at one end.I am trying to find details for a component that I think has failed or partly failed.I think this diode is faulty as it seems to be pulling a signal rail up, but not fully.With the diode removed the signal rail is at 0v, but with the diode in place it's at 12.6v, the supply rail is 28.8v.The signal rail is between the output of aCNY17Optocoupler and the gate of aBUZ10Power MOSFET.Thanks for your time.Best Regards.

author: GBowes
author_rank: Contributor
timestamp: August 14, 2016, 05:14:55 pm
content: A little more information might be helpful if you want people to help.I started to make some comments but there is really too little to go on.Can you post a schematic at least of the connections to the opto outputs, the MELF in question, and the Mosfet gate and showing the supply rail and the "signal "railQuote from: Mad Professor on August 14, 2016, 11:24:51 am
Miniature cylindrical can crystals: any gotchas? - Page 1
Forum section: electronics / beginners

author: magic
author_rank: Super Contributor
timestamp: August 08, 2021, 09:03:17 am
content: I recently found that high frequency (MHz) quartz resonators are available in 3x8mm cylindrical cans similar to common 32kHz crystals and in smaller yet 2x6mm cans. The latter has to be really small inside; narrower than even the SMD crystals I have seen.Unfortunately, the 2x6mm cans are only found on auction sites without datasheets, so I'm not entirely sure what to expect. Are those things likely to be drop-in substitutes for common HC49 crystals? Is there any "bigger is better" when it comes to quartz?My need right now: free up a bit of space in a commercial USB device by replacing a 12MHz HC49 crystal with something smaller. Accuracy requirement is a modest 500ppm.I generally always believed that quartz is quarts, nothing to see here, but then one day I discovered overtone crystals

author: Gyro
author_rank: Super Contributor
timestamp: August 08, 2021, 09:44:01 am
content: I'm not sure if it only applies to 32kHz tuning fork crystals in that can size, but I suspect that crystals of that size might have a lower maximum drive capability compared to HC49 packaged ones.Comparing the specs of the smallest SMD crystals ought to give you some sort of indication.

author: magic
author_rank: Super Contributor
timestamp: August 08, 2021, 03:49:51 pm
content: OK, I did my homework.It appears that the smallest SMD crystals out there are actually 1.2×1mm, much smaller than I thought. So 2mm diameter doesn't seem that suspicious anymore. Specs for load capacitance and ESR are similar to the big ones, but maximum drive level is lower indeed - typically 50~100µW instead of 500~1000µW.Drive level is ESR times RMS crystal current squared and some good people helpfully advise that crystal current can be estimated by measuring RMS voltage swing at the input side of the oscillator amp (with a low capacitance probe) and dividing by reactance of the load capacitor plus any stray capacitance.Assuming 19pF total capacitance we get 700Ω at 12MHz. With a pretty high (IME) input voltage swing of 0.5Vrms (1.4Vpp) we get 0.7mArms and it takes 100Ω ESR to get 50µW, while crystals in that range are specified 30Ω max.If my math is right, it seems that even small crystals in the 10~20MHz range are unlikely to be overdriven by a typical MCU oscillator.If those round can crystals don't operate on some completely different principle I suppose they are gonna be good.
Minilab 604 capacitors - Page 1
Forum section: electronics / beginners

author: viorel
author_rank: Contributor
timestamp: July 19, 2022, 05:39:12 am
content: Hi everybody.I have a BWD Minilab 604 V2 and it has this power source (see attached diagram). Many of those caps are tantalum and while I agree there's precious little room on the PCB to work with, I think at these low values it would be easy to swap them for electrolytics. The reason I am considering this is that one of the caps in the picture is blown already (that is how I bought the instrument). I have not yet powered it up so don't know if this affects anything or how. I know that one is blown because it has exploded. Still hanging on to the PCB but it is in a sorry state.The blown cap is BP9 in the diagram. BP10, C6,9, 69 and 70 are also Tantalum. You can find these at the right side halfway up the page.Not sure why some caps are labelled "BP" - bypass maybe?Can someone with a better understanding of electronics please advise if I can use electrolytics here?

author: ledtester
author_rank: Super Contributor
timestamp: July 19, 2022, 01:50:40 pm
content: Well, the TI datasheet recommends a ceramic or tantalum capacitor for BP9 and BP10. See section 9.2.1 of:https://www.ti.com/lit/ds/symlink/lm317.pdfHowever, the suggested value of that capacitor is quite small -- 0.1u to 1.0u. Not sure why they are using 10u there.This stackexchange question suggests that the recommendation of ceramic and tantalum caps at the input have to do with ESR concerns:https://electronics.stackexchange.com/questions/64063/how-do-i-decide-what-capacitor-to-use-in-a-circuitAs for the output capacitors C69 and C70, I'm sure you could replace those with electrolytics.

author: viorel
author_rank: Contributor
timestamp: July 20, 2022, 01:40:02 am
content: Thank you very much.Now I realise I should have checked the datasheet.Seems you're right. And it seems my guess as to why they label some of these capacitors "BP" instead of just "C" was right too.Not sure about why they use a higher capacitance than recommended, maybe shooting for a lower ESR? In which case why not use ceramics?Anyway. Looking for some higher voltage Tantalums I see they get very expensive very quickly. Just trying to cover the possibility that this one blew up due to some higher than allowed transient voltage.