hybridfree/eevblog-posts huggingface dataset:
What is this rubbery stuff inside this electrical box? (pic) - Page 1
Forum section: electronics / beginners

author: Jay112
author_rank: Regular Contributor
timestamp: July 31, 2018, 10:14:14 pm
content: Can you please tell me what is the rubbery stuff that's half-filling this electrical box?https://ibb.co/iSP8veWhat is it for? Is it just to hide the components underneath? Or maybe is it to prevent arcing?Thanks

author: amyk
author_rank: Super Contributor
timestamp: August 01, 2018, 12:33:41 am
content: https://en.wikipedia.org/wiki/Potting_(electronics)
What is this schematic symbol? Arrow with a circle around it - Page 1
Forum section: electronics / beginners

author: cdevidal
author_rank: Regular Contributor
timestamp: March 12, 2024, 02:16:10 am
content: It's found on page 1 ofthe datasheet for the LM386 audio amplifier schematic. I doubt it's a current source, which I've only ever seen depicted as adisconnected arrow inside a circle. But I'm open to correction on that.

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 12, 2024, 02:18:35 am
content: It's a current source.

author: golden_labels
author_rank: Super Contributor
timestamp: March 12, 2024, 03:56:11 am
content: As SiliconWizard said, but don’t treat it as a specific discrete component. For integrated circuits schematics depict behavior, not the actual implementation. In practice it’s likely an output of a current mirror.

author: sparkydog
author_rank: Regular Contributor
timestamp: March 12, 2024, 04:56:31 pm
content: Quote from: golden_labels on March 12, 2024, 03:56:11 am...or an LED driver. Or itcouldbe a discrete component, e.g. an Onesmi NSI series CCR. Not saying it'slikely, but it's possible...

author: golden_labels
author_rank: Super Contributor
timestamp: March 13, 2024, 02:32:22 am
content: LM386 is a 8-pin PDIP/SOIC package. I’m pretty certain it doesn’t contain a discrete component. In particular not a DPAK package, which is physically larger.

author: tooki
author_rank: Super Contributor
timestamp: March 15, 2024, 01:02:20 pm
content: Quote from: sparkydog on March 12, 2024, 04:56:31 pmYeah, no. Zero percent chance it’s a discrete component here.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 15, 2024, 02:20:18 pm
content: LM386 is one of those parts old enough to 1. have a fairly representative schematic in the datasheet already, but even more so, 2. have been decapped and reverse-engineered; you can inspect the physical transistors on die at your leisure.I don't remember it exactly, but a typical implementation in those days, was lateral PNP current mirrors. The "lateral" detail is important because it's a cheap way to make poor quality PNPs -- hFE is quite low, which has consequences for how the mirror is designed. For sourcing bias current into other (mostly NPN based) circuits, they're perfectly suited.Related:http://www.righto.com/2020/06/reverse-engineering-and-comparing-two.htmlI don't actually find a die photo offhand, but this isn't too surprising as the subject is very poorly represented by Google Search.Tim
What is this sensor & where to buy - Page 1
Forum section: electronics / beginners

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: October 10, 2016, 02:49:27 am
content: Attached find sensors used in Milk fact detection machines. Many companies uses it likehttp://www.ekomilk.eu/products/ekomilk-standardmultra-proWhere to buy these sensors?

author: Habropoda
author_rank: Regular Contributor
timestamp: October 10, 2016, 03:18:24 am
content: It's an Ekomilk Milk Analyzer Sensor and you can get them from PK Enterprises56, ANDIYUR POST, DIST- KRISHNAGIRI, Uthangarai - 635307, Tamil Nadu, India, Mr. Pream Kumar P (Proprietor)I have on hooked up to my Arduino and it works great.

author: ebclr
author_rank: Super Contributor
timestamp: October 10, 2016, 03:25:00 am
content: How this sensor works ?

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: October 11, 2016, 10:03:44 am
content: @Habropoda , how does this sensor works on arduino. I have also arduino card, I can use.

author: Habropoda
author_rank: Regular Contributor
timestamp: October 12, 2016, 12:31:07 am
content: The part about having the sensor and using it on the Arduino was a joke. I do not own one of those sensors. Sorry, I suppose I should not do that in the beginners' section.I found the info about the supplier here:http://www.tradeindia.com/fp3142203/Ekomilk-Milk-Analyzer-Sensor.htmlThey list the phone number as +919789252195. You might want to contact them. People like that are often happy to discuss the operation of their equipment.
What is this smd component next to 5.8 antenna - Page 1
Forum section: electronics / beginners

author: Erwin Ried
author_rank: Regular Contributor
timestamp: February 06, 2020, 12:01:21 am
content: Hi, I have a small camera with a 5.8ghz transmitter that was not working properly (very weak signal) and trying to adjust the antenna ground, I desoldered (and lost) a component by mistake. Can anyone help me identify which component did I remove?:As shown it is connected to the central pole of the antenna.More images:https://www.banggood.com/Eachine-TX02Pro-TX02-PRO-with-Smartaudio-AIO-5_8G-40CH-200mW-VTX-700TVL-14-Cmos-FPV-Camera-NTSC-p-1421133.html?rmmds=myorder&cur_warehouse=CNThanks a lot!

author: xrunner
author_rank: Super Contributor
timestamp: February 06, 2020, 12:12:34 am
content: Might be an inductor ... hard to really say.

author: Erwin Ried
author_rank: Regular Contributor
timestamp: February 06, 2020, 12:24:52 am
content: One hint: it is not a 0 ohm resistor. I connected one and the board gets really really hot fast.

author: tautech
author_rank: Super Contributor
timestamp: February 06, 2020, 12:33:38 am
content: Most likely as it's unmarked a RF coupling cap. Leave it there.

author: PA0PBZ
author_rank: Super Contributor
timestamp: February 06, 2020, 08:41:08 am
content: Quote from: Erwin Ried on February 06, 2020, 12:24:52 amThen it must be a capacitor, but the value is anyone's guess. If it is just coupling 100-1000 pF should work but if it is also for impedance matching it could be anything from a few pF's to 50 pF and critical.

author: Erwin Ried
author_rank: Regular Contributor
timestamp: February 06, 2020, 10:18:35 am
content: Quote from: PA0PBZ on February 06, 2020, 08:41:08 amI think you are correct!. I am not sure if I would be able to measure its value from a replacement I already ordered but thanks
What is this SMD component soldered in my microphone? - Page 1
Forum section: electronics / beginners

author: zirconx
author_rank: Contributor
timestamp: March 24, 2019, 09:39:47 pm
content: I salvaged a mic element from a USB headset. I might use it in a simple amplifier-speaker circuit, or to visualize sound on my oscilloscope (when it arrives, it's in the mail). I'm aware this kind of mic needs a +5v signal to operate, and that I'll need to filter that back out with a capacitor.I see what looks like a surface mount device soldered onto the bottom of the mic. What do you think this is?I did some googling and found this image fromthis site:So maybe it's that resistor? I don't see this on all microphones though (looking at photos on the internet).Thanks.

author: Brumby
author_rank: Unknown
timestamp: March 24, 2019, 11:24:45 pm
content: A photo of the actual component might be better for identification.We understand that it will be small and possibly difficult to photograph well, but that doesn't mean it won't be helpful.

author: zirconx
author_rank: Contributor
timestamp: March 25, 2019, 12:04:42 am
content: Doh! I had carefully taken a photo but then completely forgot to attach it. Here it is. Looks like a diode, right?

author: zirconx
author_rank: Contributor
timestamp: March 25, 2019, 12:43:18 am
content: So what would that be for, why would there be a diode here?

author: Jwillis
author_rank: Super Contributor
timestamp: March 25, 2019, 12:48:22 am
content: Looks like a diode and a cap (look between the solder joints)in parallel. To dampen switching spikes?
What is this SOT23 Transistor? - Page 1
Forum section: electronics / beginners

author: cube
author_rank: Newbie
timestamp: December 03, 2024, 10:07:37 pm
content: Hi all.I'm having trouble working out what's wrong with the PWM circuit that controls the heated insoles for my ski boots. And I'm new to SMD components.There are a couple of SOT23 transistors marked 4Gt 64 which I think are BC860C and do the PWM, the collector of one of these is connected to the base of the transistor that does the actual switching for the heater element - this switching transistor is also a SOT23 package and marked A6DA5. I just can't work out what this is. I think it's where the fault lies because it measures 4 ohms from base to emitter. It has to switch about 400ma. When I look up A6D for SOT23 package I find MMUN2114 but that is only rated to 100ma collector current unless I read it wrong.I've attached a picture of it. Anyone got any suggestions on what this SOT23 A6DA5 could be?Thanks.

author: thm_w
author_rank: Super Contributor
timestamp: December 03, 2024, 10:22:22 pm
content: Can you tell what the the bottom left and right side pads go to? Might help to determine the part.The top left is obviously base or gate.It doesn't seem to match the silkscreen of a MMUN2114.Have you measured the heater wire resistance and verified that part is still OK?

author: cube
author_rank: Newbie
timestamp: December 03, 2024, 10:41:00 pm
content: Thanks for replying. Yes, checked the heater element on another battery pack and it's ok.The +ve from the 4.8v battery back goes straight to one side of the element.The other side of the element goes to the middle-right of A6DA5 - guessing this is the collector.The bottom-left of A6DA5 goes to -ve of the 4.8v battery pack, so A6DA5 switching the connection from the element to -ve.Hope that helps, I can post some more images or diagrams if needed.Thanks!

author: thm_w
author_rank: Super Contributor
timestamp: December 03, 2024, 10:55:43 pm
content: OK so low side switched.Should be alright to put in a suitably rated N channel FET (2A+ 20V+), and see if it works as expected? Assuming you've already removed the old part and the 4 ohm is on the part itself.

author: fzabkar
author_rank: Super Contributor
timestamp: December 04, 2024, 05:37:52 pm
content: IRLML2402TR, International Rectifier / Infineon, n-channel MOSFET, 20V, 1.2A, 0.25 ohm RDSon, SOT23, marking Aywlc:https://www.infineon.com/dgdl/irlml2402pbf.pdf?fileId=5546d462533600a401535664e5ef25fahttps://www.aliexpress.com/w/wholesale-IRLML2402TR.html(photos)http://markingcodes.com/search/c/a6

author: cube
author_rank: Newbie
timestamp: January 01, 2025, 01:42:26 pm
content: Sorry for the delayed reply and thanks very much for your help @thm_w and @fzabkar. I was really busy just before Christmas then away.I found some A2SHB SOT23 N MOSFETs on ebay rated at 20v 3A. I bought some of these and soldered one into each PCB to replace the faulty one, and was delighted it fixed the problem so I had nice warm feet while away skiing!So a big thank you for your help, I've not done much SMD work or diagnosing faults like this, great result.
What is this steel type/finish ? (cd/floppy drive enclosure style) - Page 1
Forum section: electronics / beginners

author: ratatax
author_rank: Regular Contributor
timestamp: September 04, 2020, 10:05:18 am
content: Hi,I'm looking to make a product which would have a sheet metal enclosure, matte gray color, but I struggle to find the name of the finish I need.I noticed most CD/floppy drives use the kind of sheet metal I'd need (see attached pic), but the perfect finish confuses me, there are no processing/sheet bending scratches. It doesn't seems to be painted (acetone does nothing on it). However, scratching the surface reveals the more shiny/reflective nature of the raw steel.Do you know what is it ?

author: Psi
author_rank: Super Contributor
timestamp: September 04, 2020, 10:16:21 am
content: I always assumed it was some sort of anodizing.

author: westfw
author_rank: Super Contributor
timestamp: September 04, 2020, 10:38:33 am
content: “Powder coating”?Electrostatic tools are used to distribute a fine coat of pigmented power over the surface of a conductive base material, and the they go into the oven to fix and melt the polymer powder and adhere it to the base.Alternately, they’re painting processes are better than you are used to. two-part Epoxy aor urathane paints are pretty common and harden to solvent-resisting finished. Or UV-cured.

author: RoadRunner
author_rank: Frequent Contributor
timestamp: September 04, 2020, 10:46:15 am
content: Some sort of Zinc plating over sheet metal. I guess.

author: nali
author_rank: Frequent Contributor
timestamp: September 04, 2020, 10:51:41 am
content: Zintec - Mild steel with zinc electroplate

author: ratatax
author_rank: Regular Contributor
timestamp: September 04, 2020, 12:39:33 pm
content: Seems to be Zintec right ! It must be plated after processing though, to have a perfect finish. I'll check with my local sheet metal supplier if they can do that

author: rdl
author_rank: Super Contributor
timestamp: September 04, 2020, 12:51:02 pm
content: If it's metallic appearing it may have zinc plating, but matte gray as you describe is most likely coil coated or prepainted steel.

author: exmadscientist
author_rank: Frequent Contributor
timestamp: September 04, 2020, 05:13:50 pm
content: Sounds like you're looking for SECC steel or one of its JIS G3313 relatives. This is a very common material type in Asia, but its specification is written differently from those used in the US or Europe, in more than cosmetic ways, so it can confuse Western engineers.You might also find this vendor propaganda interesting (for reference only, no endorsement):https://www.jfe-steel.co.jp/en/products/sheets/catalog/b1e-003.pdf
What is this symbol called? - Page 1
Forum section: electronics / beginners

author: Carabus
author_rank: Contributor
timestamp: November 07, 2021, 06:10:28 pm
content: It is in a test. Possible answers are(translated from Lithuanian)a) Magnetron (Magnetronas)b)Gaussotron (Gausotronas)c)Hallotron (hall effect) (Holotronas)https://freeimage.host/i/5ExmQ4

author: spicey
author_rank: Newbie
timestamp: November 07, 2021, 06:15:21 pm
content: Hall sensor.Source:https://studfile.net/preview/5303340/page:3/

author: Carabus
author_rank: Contributor
timestamp: November 07, 2021, 06:17:42 pm
content: Thanks

author: jesuscf
author_rank: Frequent Contributor
timestamp: November 08, 2021, 07:15:07 am
content: Interesting! I didn't know it could be drawn like that. Always seem it as a square with a giant X in the middle.
What is this symbol in schematic?  - Page 1
Forum section: electronics / beginners

author: sephtron
author_rank: Newbie
timestamp: March 16, 2020, 08:26:53 am
content: Hello! I'm a beginner to PCB design and this is my third project - making a version of the Chronio DIY Watch.I've been trying to re-create the schematic in KiCAD but have hit a road block.What is this symbol (please see circled in red)? How do I go about adding it in KiCAD?I've attached the Chronio DIY Watch schematic and my work-in-progress version.Thanks!

author: Siwastaja
author_rank: Super Contributor
timestamp: March 16, 2020, 08:34:49 am
content: Based on the context, specifically the use in the "Programming Connector" area, someone's own way to describe a connector pin, maybe. Maybe it tries to resemble something physical if you zoom in? At that zoom level, looks like mess.

author: Dave
author_rank: Super Contributor
timestamp: March 16, 2020, 08:37:38 am
content: Exposed pads on the PCB for using withpogo pins.The schematic symbol is showing just that, a pogo pin. Personally, I'd draw a simple circle to indicate some sort of contact, as the pogo pin is not actually part of this circuit, but to each their own.Here's the image of the board, you can see the five exposed pads which are labelled "Programming Connector" in your schematic.https://hackaday.io/project/12876/gallery#940b5e62214c2c979266ebd52c3ad9dd

author: Nusa
author_rank: Super Contributor
timestamp: March 16, 2020, 08:43:06 am
content: You can also see the SI/SO/SCK pads on the top side of that same picture. With solder on them.So in this case the symbol referred to pogo pin pads on the board. Can't say I've ever seen that symbol before, but it was obvious enough from the context.

author: Siwastaja
author_rank: Super Contributor
timestamp: March 16, 2020, 08:54:35 am
content: Oh yes, makes sense. Of course, the symbol is wrong because the watch PCB likely isn't supposed to use the pogo pins - it's the connector jig which uses the pins. The correct symbol to denote a PCB pad for programming with pogo pins is the test point symbol. A few different kinds are commonly used, as listed in a reply here:https://electronics.stackexchange.com/questions/254828/diamond-symbol-in-schematic

author: sephtron
author_rank: Newbie
timestamp: March 16, 2020, 09:06:48 am
content: > So in this case the symbol referred to pogo pin pads on the board.Yeah I just took a look at that image and that does makes sense. Thanks for your input guys!
What is this that came with my new fluke 87-V? - Page 1
Forum section: electronics / beginners

author: IonizedGears
author_rank: Regular Contributor
timestamp: January 23, 2013, 03:35:00 am
content: N/A

author: Stephenniall
author_rank: Contributor
timestamp: January 23, 2013, 03:53:39 am
content: I'm guessing they're just protective covers for the Banana jacks, Whilst shipping.They're probably to stop dust/debris getting into the Jacks.Stephen

author: IonizedGears
author_rank: Regular Contributor
timestamp: January 23, 2013, 03:56:22 am
content: But wait, they came in a separate bag, like if you were to buy components from a retailer such as radioshack. Not pre installed. The problem also is that i tried to get them to fit on the bananas of the probes but they are a tight fit and they wont even go into the input on the meter.

author: nanofrog
author_rank: Super Contributor
timestamp: January 23, 2013, 06:07:46 am
content: You want a tight fit on the probes (banana end) IMHO, as they'll loosen up over time.

author: Wytnucls
author_rank: Super Contributor
timestamp: January 23, 2013, 07:51:18 am
content: They are earplugs actually, for the day you want to measure 1000V, with the leads in the wrong jacks.

author: nanofrog
author_rank: Super Contributor
timestamp: January 23, 2013, 08:07:30 am
content: Quote from: Wytnucls on January 23, 2013, 07:51:18 amThanks for that.

author: SeanB
author_rank: Super Contributor
timestamp: January 23, 2013, 04:27:29 pm
content: Could be feet for the holster.

author: psycho0815
author_rank: Regular Contributor
timestamp: January 24, 2013, 09:23:59 am
content: I'd say they're propably plugs to cover the two inputs you're probes aren't in, to keep dust and maybe moisture out.I've gotten some plugs like that with a meter of mine. they look fairly different though.

author: EEVblog
author_rank: Unknown
timestamp: January 24, 2013, 11:35:11 am
content: Yep, plugs for the unused jacks. For use in more extreme environments.Dave.

author: IonizedGears
author_rank: Regular Contributor
timestamp: January 25, 2013, 12:41:16 am
content: Thanks guys.

author: rsjsouza
author_rank: Super Contributor
timestamp: January 25, 2013, 12:12:08 pm
content: IonizedGears, I was reading your post and must say that you are starting on the right track with absolutely one of the best tools in your hands!Welcome to electronics and happy "hobbying"!

author: SLJ
author_rank: Frequent Contributor
timestamp: January 25, 2013, 01:04:53 pm
content: Wow, an 87V and your 15? That's a great start. Those plugs are a good idea. My 87V/E2 kit did not come with them. Guess I'll have to find some.
What is this thing? - Page 1
Forum section: electronics / beginners

author: antlord
author_rank: Newbie
timestamp: September 11, 2013, 02:55:06 pm
content: Hi, complete beginner here. Wasn't sure where to post this, but does anyone know what this thing is?https://docs.google.com/file/d/0B96ZKoQO2CBjYnRaakZqQ2pLejQ/editCan't find any datasheet, only some schematics on a paid site that I can't view. Yanked it out of an old cassette for fun.Thanks.

author: Kjelt
author_rank: Super Contributor
timestamp: September 11, 2013, 03:06:19 pm
content: Yanked it out a KXW-S70 ? Looks like another custom Yamaha chip, who knows, might be a microcontroller with special peripherals?

author: Kjelt
author_rank: Super Contributor
timestamp: September 11, 2013, 03:19:29 pm
content: Ok you can download the service manual here:http://www.owner-manuals.com/KXWS70-service-manual-YAMAHA.htmlAnd in it you can find that the XL987B00 is in fact a LC65204A-4B83 a microcontroller and you can see it is a 4 bit yes no typo microcontroller and its pinout. Not sure what you want to do with it but there it is.

author: antlord
author_rank: Newbie
timestamp: September 11, 2013, 03:24:26 pm
content: Wow, many thanks. I'm also unsure of what to do with it, to be honest.

author: Kjelt
author_rank: Super Contributor
timestamp: September 11, 2013, 03:29:34 pm
content: Well it is not gonna be easy to find a compiler or other tools for this old microcontroller. Chances are that this micro was programmed directly in assembli, probably OTP so can not be erased. So unless you know someone with a defective KXW-S70 or like to hang it on the wall for decorative purposes I can't think of anything to do with it. But nice to see this old kind of elektronics pop up
What is this thing on processor? - Page 1
Forum section: electronics / beginners

author: canol
author_rank: Contributor
timestamp: March 31, 2014, 01:41:04 pm
content: Hello, this screenshot is from one of the videos of Dave. I wondered what the black thing on the processor is and why it is used?

author: Kjelt
author_rank: Super Contributor
timestamp: March 31, 2014, 01:51:58 pm
content: That is aCOB: chip-on-board; a bare silicon chip, that is usually an integrated circuit, is supplied without a package.Since it has no package it would be extremely vulnerable so the manufacturers put a blob of stuff on it that could be anything from epoxy to resin.Here is what it kinda looks like without the blob

author: canol
author_rank: Contributor
timestamp: March 31, 2014, 02:16:15 pm
content: Thank you very much. Why do they prefer chip-on-board? Is it cheaper?

author: N2IXK
author_rank: Frequent Contributor
timestamp: March 31, 2014, 02:18:36 pm
content: Cheaper, and non-repairable...

author: mariush
author_rank: Super Contributor
timestamp: March 31, 2014, 02:25:11 pm
content: Have a look at this video, from 15:00 onwards. It shows how a chip used to be put into the classic shape of a DIP package :It was a lot of work. Now the technique is a bit faster and easier.The chips (dies) are usually made in one place, shipped to some other place where the dies are briefly checked to make sure they're good and then it takes time to solder the wires to the leads of the package, then you put the whole thing in plastic or epoxy and then companies test the package again, sometimes even doing some long tests to make sure they run at various temperatures according to specifications.The dies are cheaper because the manufacturer sends them directly with less checking and there's less costs (no need to ship them to be packaged and tested) and some companies will even send the dies untested and estimate a percentage as bad and you simply test them and throw away the non working ones. Or, in the case of some microcontrollers for example, you can buy dies that have a part of them faulty and use these microcontrollers in products that don't use that feature (for example ADC or UART not working, which won't matter in a "blink leds" toy)
What is this thing? - Page 1
Forum section: electronics / beginners

author: shane_95
author_rank: Regular Contributor
timestamp: July 04, 2012, 04:08:17 am
content: I got this out of a 12v power supply that I killed what is it?

author: IanB
author_rank: Super Contributor
timestamp: July 04, 2012, 04:19:49 am
content: Can you make a picture with brighter lighting and better focus?Also, what kind of "12 V power supply" exactly?

author: shane_95
author_rank: Regular Contributor
timestamp: July 04, 2012, 04:22:59 am
content: It's a 12v ac/dc supply for model trains.thats the best i can do for the picture at the moment, it was taken from an ipad sorry

author: pickle9000
author_rank: Super Contributor
timestamp: July 04, 2012, 04:26:47 am
content: It looks like a self resetting breaker. Are there contacts inside?...mike

author: shane_95
author_rank: Regular Contributor
timestamp: July 04, 2012, 04:30:14 am
content: is this any beater

author: pickle9000
author_rank: Super Contributor
timestamp: July 04, 2012, 04:32:39 am
content: It's a breaker, it has contacts....mike

author: shane_95
author_rank: Regular Contributor
timestamp: July 04, 2012, 04:33:52 am
content: what do they do then?

author: IanB
author_rank: Super Contributor
timestamp: July 04, 2012, 04:40:30 am
content: One of the contacts is on a bimetallic strip. If things get too hot inside the power supply due to overload the metal strip heats up and bends away, breaking the circuit and cutting off the power. After things have cooled down again it remakes the contact and the power comes back.

author: shane_95
author_rank: Regular Contributor
timestamp: July 04, 2012, 04:41:33 am
content: oh ok
what is this type of wire called? - Page 1
Forum section: electronics / beginners

author: josephpate
author_rank: Contributor
timestamp: June 19, 2018, 03:25:09 pm
content: I've been obsessed with retractable audio cables recently, but all of them seem to be TRS, and I need one that is TRRS. I was thinking of making my own, which means I need a four conductor super flimsy wire. I could modify a USB cable, but I think I want some of this wire to use in future projects.Is there a specific term to search for to find this stuff?for the record this is what I'm talking about:https://smile.amazon.com/I2R-Strikeline-Retractable-Certified-Lightning/dp/B00B3ISAMS/ref=sr_1_17?ie=UTF8&qid=1529421542&sr=8-17&keywords=retractable+cable

author: mikerj
author_rank: Super Contributor
timestamp: June 19, 2018, 10:09:07 pm
content: TRRS retractable cables are uncommon, but they are available:Male to maleMale to female

author: oPossum
author_rank: Super Contributor
timestamp: June 19, 2018, 10:09:17 pm
content: Tinsel wire

author: josephpate
author_rank: Contributor
timestamp: June 20, 2018, 02:37:28 am
content: is there a specific name for this flat type of tinsel wire? google search just shows really thin wire.
What is this Voltage, "Vtouch" meaning - Page 1
Forum section: electronics / beginners

author: Freshman
author_rank: Regular Contributor
timestamp: May 22, 2024, 09:16:03 am
content: In this product manual,https://www.megger.com/sites/g/files/utfabz201/files/acquiadam_assets/2022-07/EVCC300_UG_en.pdf?changed=1669681566the definition of "Vtouch" voltage is not given and not sure how to use it.Can someone tell me what is the meaning of Vtouch voltage, between which points it is measured and when should I use it?

author: soldar
author_rank: Super Contributor
timestamp: May 22, 2024, 09:31:15 am
content: See if this helps:
What is this Zener doing? - Page 1
Forum section: electronics / beginners

author: capella_ben
author_rank: Newbie
timestamp: April 02, 2022, 07:56:39 am
content: Hi,I'm trying to understand the circuit for a treadmill motor controller. I have traced through the main part of the circuit in the attachment.It has the usual rectifier then a couple of 500V, 8A mosfets in parallel (I have not done all the stuff to drive these).It all makes sense except for the 15V 1W zener and the 2 10K 7W resistors. Can anyone tell me what this does? Or perhaps I have missed something in my reverse engineering...

author: hamster_nz
author_rank: Super Contributor
timestamp: April 02, 2022, 08:07:33 am
content: Something to discharge the cap to 'safe' levels when it is powered off?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 02, 2022, 08:35:41 am
content: Sure there's nothing attached to it? Could be like a high-side supply to go with the shunt resistor.Tim
What is this zilog part? - Page 1
Forum section: electronics / beginners

author: makerimages
author_rank: Regular Contributor
timestamp: November 18, 2013, 05:01:34 pm
content: Hey, aquired an unnamed(seriously, nothing on there except the reverse R tied into a U symbol) board for parts.On it I found the thrill-giver, a Zilog part, might be good since I am currently in the process of making a z80 computer.But, the part nr. on that part turns out empty in google. Can any of you guys guess what it is? And what the board might be?Part and board:

author: Simon123
author_rank: Regular Contributor
timestamp: November 18, 2013, 05:41:15 pm
content: It could be z8 core microcontroller, take picture of connections to it.

author: free_electron
author_rank: Super Contributor
timestamp: November 18, 2013, 06:24:02 pm
content: looks like an old Pay-tv decoder or satellite receiver.Mask rommed Z8 cpu. useless.

author: MrAureliusR
author_rank: Unknown
timestamp: November 19, 2013, 07:18:36 am
content: free_electron is probably right, it's probably a mask ROMed one...you can pick up Z80's on eBay for fairly cheap, I've got a couple floating around from eBay. Also pick up a SIO and/or PIO, DART, or CRC depending on what you're building.I found the Z80 to be a lot of fun to build and work with! I didn't get terribly far but I was interfacing to it with a basic command line 'monitor' running through a serial connection -- pretty cool stuff!

author: amyk
author_rank: Super Contributor
timestamp: November 19, 2013, 12:44:27 pm
content: This pagerelated to satellite TV decoders suggests free_electron is right (search Zilog on that page and note the part numbers.)According to a brief glance atthis documentyou can force a Z8 ROM version to execute code from external memory.
What is this? - Page 1
Forum section: electronics / beginners

author: timelessbeing
author_rank: Frequent Contributor
timestamp: November 27, 2011, 07:35:14 am
content: I found it amongst some bits'n pieces I had.

author: McMonster
author_rank: Frequent Contributor
timestamp: November 27, 2011, 07:49:13 am
content: Possibly some kind of light or color sensor.

author: 8086
author_rank: Super Contributor
timestamp: November 27, 2011, 02:54:28 pm
content: I would agree with above. Possibly light-to-frequency or something seeing as it has some kind of silicon as well as the sensor.What I am more interested in though, is what camera you used to get up close so well to take the picture?

author: ndictu
author_rank: Regular Contributor
timestamp: November 27, 2011, 03:30:59 pm
content: Quote from: 8086 on November 27, 2011, 02:54:28 pmFrom the Exif data:Quote

author: timelessbeing
author_rank: Frequent Contributor
timestamp: November 28, 2011, 10:26:24 am
content: It's an ordinary point&shoot camera in macro mode. It took some time to set up the shot and adequate lighting without too much reflection. I think the most important trick was to set the camera down and use a timed shutter to achieve a still shot. But I don't think it turned out THAT great. It's rather grainy, the highlights are blown out and the depth of field is very shallow (leads are out focus).

author: metalphreak
author_rank: Frequent Contributor
timestamp: November 28, 2011, 12:33:28 pm
content: I've seen some tiny solar cells that look similar to that. I doubt thats what it is though.

author: sonicj
author_rank: Frequent Contributor
timestamp: November 28, 2011, 11:15:03 pm
content: i have this same camera and imo, it takes OK macro shots. like timelessbeing mentioned, it takes a bit of setup and a timed shutter release or remote to acquire good results.that is a cool looking package, whatever it is!-sj

author: Psi
author_rank: Super Contributor
timestamp: November 29, 2011, 12:46:36 am
content: Here's the best macro shot i can get...with my PHONE!(Nokia N900)The chip in the background is a sensor from an airport Xray machine, basically an array of photodiodes.It's supposed to have a white phosphorescent block on top to convert xrays into light but i remove it.
What is USB Enumeration? - Page 1
Forum section: electronics / beginners

author: MrOmnos
author_rank: Frequent Contributor
timestamp: April 06, 2016, 04:47:22 pm
content: Someone please explain to me what is USB enumeration like I am five. Books are too vague and not helping. Also What are Endpoints?Here are some of the Things I understand about USB.General Packet fields except for EndpointsPacket TypesData flow typesThings I don't Understand about USBWhat are the mysterious Layers of Protocol of USB?EndpointsPipes

author: zapta
author_rank: Super Contributor
timestamp: April 06, 2016, 04:49:32 pm
content: Think of enumeration as 'mounting'.

author: rstofer
author_rank: Super Contributor
timestamp: April 06, 2016, 05:05:28 pm
content: A worthy reference:http://www.amazon.com/USB-Complete-Fourth-Edition-Developers/dp/1931448086

author: mazurov
author_rank: Frequent Contributor
timestamp: April 06, 2016, 07:01:32 pm
content: When (any) USB device resets it answers to address zero. Enumeration is giving a device an address different from zero.

author: danadak
author_rank: Super Contributor
timestamp: April 06, 2016, 07:05:24 pm
content: http://www.ftdichip.com/Support/Documents/TechnicalNotes/TN_113_Simplified%20Description%20of%20USB%20Device%20Enumeration.pdf

author: bson
author_rank: Unknown
timestamp: April 06, 2016, 09:11:56 pm
content: Bus enumeration means scanning all devices on the bus and creating a table to manage them. If a device is a hub, then it will enumerate the hub independently. All hubs and controllers sit under a logical host root node, so form a device tree according to how they're connected. Enumeration is the process of mapping this out and is done for any bus to discover what's attached to it. When you type lsusb in Linux it lists all known devices, with -t it dumps the whole bus tree.
What is wrong with this simulation? - Page 1
Forum section: electronics / beginners

author: MacIntoshCZ
author_rank: Regular Contributor
timestamp: September 28, 2024, 09:51:20 am
content: Really dont know what i am missing but there is plenty of time for inductor current to go to reach zero when switching is off.But it just wont happen. Ignore there is no gate resistor, there should be 5R, but it has no impact current anyaway.V(n008) is output of V1

author: MacIntoshCZ
author_rank: Regular Contributor
timestamp: September 28, 2024, 10:56:59 am
content: There is nothing wrong with simulation. I had the wrong approach. I realized that at the moment when the switching is off, the current will be preserved, but I did not realize that the wattage will be different, with the voltage being so large that the magnitude of the current is preserved....

author: temperance
author_rank: Super Contributor
timestamp: September 28, 2024, 12:40:10 pm
content: R5 is way to small in value.The V x s (Volt second product) product during the off time must at least equal or larger than the V x s applied during the on time. Otherwise the transformer will staircase into saturation.Instead of a resistor and a diode you can use a zener diode with a zener voltage higher than the supply voltage.
What kills all the output transistors when one shorts? Can it be prevented? - Page 1
Forum section: electronics / beginners

author: Deactivated-1
author_rank: Frequent Contributor
timestamp: August 25, 2023, 03:33:07 am
content: Is the exact reason all the other output transistors in a push pull amp usually short when just one shorts?Is it that the Collector to Emitter shorts and then the other transistors exceed the -Vbe breakdown? is it that the Collector to Base shorts and it exceeds max base current?Couldn't you prevent both by putting like a 1V zener diode from base to emitter of each transistor? In a fault the diode will probably short because of exceeding the current trough whatever base resistor there is. But as long as it protects the output transistor... Or some other type of crowbarOr much better - a current limiter for each output transistor, Or even better yet, separate drive transistors for each output transistor.

author: Kim Christensen
author_rank: Super Contributor
timestamp: August 25, 2023, 05:33:39 am
content: Usually it's the negative feedback circuitry than deals the final death blow.Image that the top rail output transistor goes shorted:As the output voltage rises, the negative feedback circuitry will cause the lower rail output transistor to turn fully on.High current will flow, until the lower rail output transistor self destructs.

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: August 25, 2023, 02:03:02 pm
content: In RF transistor amps, there is frequently a normal diode between the base and ground to prevent overvoltage on the base. Keeps bias at .6 V.These are NOT push pull but parallel or just single transistors.In MOSFET Finals a approx 5 volt zener is used.I do not think that these diodes are used in audio amps probably because of distortion, I really do not know however and maybe someone else does.
What kind of 4-pin volumer controllor is this ? Or is it broke - Page 1
Forum section: electronics / beginners

author: lordvader88
author_rank: Frequent Contributor
timestamp: January 18, 2018, 08:13:46 pm
content: I have a volume knob off a panasonic stereo, it has 4 terminals, looks like a pot, however its the type the turns forever in both directions. 2 pins are on the same PCB trace. AS I try to measure the resistance , is either open, or shorted, for every degree of turning basically. And it must have cap in it too, because if its not open or short when I stop turning it, it will be about 4-5 ohms, and start dropping down to zero.So what is it ?

author: Benta
author_rank: Super Contributor
timestamp: January 18, 2018, 08:21:17 pm
content: It's a rotary encoder. Most likely quadrature output. The volume control itself is somewhere else, digitally controlled from the encoder.

author: lordvader88
author_rank: Frequent Contributor
timestamp: January 18, 2018, 09:33:33 pm
content: ok nice...
What kind of antenna is this? - Page 1
Forum section: electronics / beginners

author: digitalnomadjc
author_rank: Contributor
timestamp: July 16, 2015, 06:18:15 am
content: I've pulled apart a wifi access point to better understand it and found a number of internal antennas.It has about 8 that all look like the attached photo, only some are different angles from others.What kind of antennas are these?

author: Psi
author_rank: Super Contributor
timestamp: July 16, 2015, 06:25:20 am
content: It's a cheap antenna. One they can punch out in massive quantitiesProbably has a name but it looks more or less like a dipole that has been folded over

author: digitalnomadjc
author_rank: Contributor
timestamp: July 16, 2015, 06:45:13 am
content: The others look like this.

author: Dago
author_rank: Frequent Contributor
timestamp: July 16, 2015, 07:20:25 am
content: It is an inverted-F antenna:http://www.antenna-theory.com/antennas/aperture/ifa.php

author: digitalnomadjc
author_rank: Contributor
timestamp: July 16, 2015, 07:22:25 am
content: Wow thanks
What kind of cables do I need? - Page 1
Forum section: electronics / beginners

author: eeguy
author_rank: Regular Contributor
timestamp: April 09, 2020, 01:41:06 pm
content: Hello, I am looking for two cables. One is the power cable-adapter (the white plug with open ended black and red wires) shown in the photo. It is to supply 12V, 4.5A. Another is some kind of extension cord for the T-connector with two thick gold plugs (I guess one end female to connect to the board and another end male to connect to the LIPO battery).For these two cables, do I need to concern about the type/thickness of the wires? Could you please tell me the name for these two cables and good place to buy them? Thank you.

author: Vovk_Z
author_rank: Super Contributor
timestamp: April 09, 2020, 08:12:29 pm
content: 4.5 A needs something about AWG 22 thickness or thicker (it depends on wire length too).

author: eeguy
author_rank: Regular Contributor
timestamp: April 09, 2020, 08:15:59 pm
content: Thanks. It seems that the white connector is: SMW250-02 made in Korea. How do I find the one that can match it and available in North America?

author: Vovk_Z
author_rank: Super Contributor
timestamp: April 09, 2020, 08:17:33 pm
content: I don't know such connector type, unfortunately (and can't help with USA shops).

author: eeguy
author_rank: Regular Contributor
timestamp: April 09, 2020, 08:19:28 pm
content: Probably it is this one.http://product.ic114.com/PDF/S/SMW250-NN.pdfWhere is no international standard on connectors?

author: Jwillis
author_rank: Super Contributor
timestamp: April 10, 2020, 05:03:17 pm
content: That is a 2 pin JST-XH . Current rating: 3 A AC/DC (AWG #22). The crimps can't really take a wire larger than 22AWG .You get them ready made on Ebay. The "T" connector is also called a DEANS connector.
What kind of cap is this? - Page 1
Forum section: electronics / beginners

author: raspberrypi
author_rank: Frequent Contributor
timestamp: February 05, 2017, 05:15:36 pm
content: It goes to my HID shop light. Takes AC 400V . IS there an equivalent that has a smaller voltage rating that is through hole size?

author: PA0PBZ
author_rank: Super Contributor
timestamp: February 05, 2017, 05:18:32 pm
content: Quote from: raspberrypi on February 05, 2017, 05:15:36 pmOf course, but please do tell what you are trying to accomplish.

author: madires
author_rank: Super Contributor
timestamp: February 05, 2017, 05:28:06 pm
content: That cap is for compensating the phase shift caused by the ballast and has to meet some safety standards. Yes, they are huge (metallized film, a few µF).

author: David Hess
author_rank: Super Contributor
timestamp: February 05, 2017, 05:58:32 pm
content: It is a 24uF 400V metalized plastic film capacitor. I am not sure what its ESR is or its ripple current capability is but watch out for these if you try to build a replacement. I doubt a bunch of leaded film capacitors in parallel will be less expensive than a real replacement.

author: raspberrypi
author_rank: Frequent Contributor
timestamp: February 13, 2017, 07:48:20 am
content: I was just curious as to what kind it was. It actually says the ESR on the label. I thought this was for striking the bulb to turn on the arc when it was cold. Whats interesting is you can't turn the light off then back on until it is cold. It will just make a tiny blue spark when you try to turn it on when its hot.
What kind of circuit simulator is this? - Page 1
Forum section: electronics / beginners

author: Beamin
author_rank: Super Contributor
timestamp: December 22, 2019, 12:53:37 am
content: Seems like a step up from the free web based one I was using and would be helpful for learning or estimating values of parts.

author: JackJones
author_rank: Regular Contributor
timestamp: December 22, 2019, 03:23:22 am
content: Looks like this one:http://everycircuit.com/appIt doesn't start up for me for some reason though.

author: Nerull
author_rank: Frequent Contributor
timestamp: December 22, 2019, 05:07:00 am
content: EveryCircuit uses Google's "Native Client" (NaCl) which is a sandbox system that allows webapps that use native code, a while ago an update disabled its use by apps that aren't installed through the chrome store. Everyone is supposed to move to WebAssembly, but every circuit hasn't.There is a way to reenable it - to go chrome://flags/#enable-nacl and hit 'Enabled'. Apparently google laid off its entire Native Client dev team, so who knows if the sandbox is still secure and there seems to be no way to enable it on a site-by-site basis.
What kind of connector do I need here? - Page 1
Forum section: electronics / beginners

author: GUGLHUPF
author_rank: Newbie
timestamp: May 23, 2022, 03:47:13 pm
content: I want to get this module. I do not know what the connector is. Description just says 4 pin 1.25mm. I compared to JST and this looks different. Can someone help?Thank you

author: tooki
author_rank: Super Contributor
timestamp: May 23, 2022, 08:49:00 pm
content: Did you go look on Digi-Key under rectangular connector headers for that pitch and pin count? They don’t carryeverything, but they do carry a lot, so it’s a great first place to look.

author: free_electron
author_rank: Super Contributor
timestamp: May 23, 2022, 09:24:58 pm
content: looks like one of hirose's connectors

author: inse
author_rank: Super Contributor
timestamp: May 24, 2022, 05:24:36 am
content: Redundant post

author: tepalia02
author_rank: Regular Contributor
timestamp: May 29, 2022, 11:03:17 am
content: Have you tried these?https://www.amazon.com/Micro-4-Pin-Female-Connector-Cables/dp/B07T792829

author: janoc
author_rank: Super Contributor
timestamp: May 29, 2022, 02:52:25 pm
content: Try here:https://connectorbook.com/identification.html?st=1&nm=by_traits&bm=by_componSpecifically:https://connectorbook.com/identification.html?st=1&nm=by_traits&bm=by_compon&c=interior_rect_conn&u=wire_to_board_conn&o=discrete_1row_w2b_conn&f=discrete_1row_w2b_conn_1p2
What kind of connector is this? - Page 1
Forum section: electronics / beginners

author: Mp3
author_rank: Frequent Contributor
timestamp: June 28, 2019, 11:07:32 am
content: I'm looking to replace a failing character LCD, but i would prefer to buy a new connector and make a new cable for the replacement display instead of cutting or desoldering the wire from the current display. I can figure out the exact size myself, but what name would i find this sort of connector at a place like Mouser?Specifically the orange 14-pin connector at the end.Many thanks in advance!

author: Richard Crowley
author_rank: Super Contributor
timestamp: June 28, 2019, 11:24:10 am
content: It looks like a bog-standard 0.1 inch (2.4mm) pitch square pin "header" style connection. Widely used in maker stuff like Arduino, etc. Confirm by measuring the pitch between pins.Note also that it depends on the exact configuration of the mating connector. If it is just 14 pins sticking out in the air, then you can use practically any 14x1 shell. But if it is the kind that is "polarized" with a "fence" on one side, then you must find a plug that fits that series of connector. Perhaps Molex KK as @Rigolon suggests. But we don't know without seeing the mating connector.Here are the 14-pin shell and the individual crimp terminals that go into the shell (after you crimp onto your wires). You can order these from a hacker-friendly vendor like Tayda, or you can spend several hours looking for them in Mouser, DigiKey, et.al. And then deal with the minimum-order quantities, etc.https://www.taydaelectronics.com/connectors-sockets/wafer-housing-crimp-terminal/serie-2500-2-54mm/housing-connector-2-54mm-14-pins.htmlhttps://www.taydaelectronics.com/connectors-sockets/wafer-housing-crimp-terminal/serie-2500-2-54mm/crimp-terminal-connector-2-54mm.html

author: Rigolon
author_rank: Regular Contributor
timestamp: June 28, 2019, 06:55:15 pm
content: Here in Brazil it's generally called KK connector.Actually, from what I know, KK is the name given by Molex. Others manufactures uses different names. But you should find it easily using this name.

author: Mp3
author_rank: Frequent Contributor
timestamp: June 29, 2019, 05:26:51 am
content: Quote from: Richard Crowley on June 28, 2019, 11:24:10 amAside from the stellar help, huge thanks to letting me know about Tayda who i never knew about until this momentI think i will be able to find the connector i need, but here is a picture of the receptacle on the main board if it helps.

author: Richard Crowley
author_rank: Super Contributor
timestamp: June 29, 2019, 12:17:24 pm
content: Note that because those PC board connectors are the "box type", the shell I recommended may not fit (or may require modification like removing the "fin keys" on the ends). An alternative may be to use a female header type connector. They are sold in strips and you cut them down to however many pins you need. But they would require to solder the wires onto the little pc pin ends. Not as elegant, but more likely to fit inside the box shell of your PC board connectors.https://www.taydaelectronics.com/connectors-sockets/pin-headers/40-pin-2-54-mm-single-row-female-pin-header.html