hybridfree/eevblog-posts huggingface dataset:
Shenzhen market, recommended buildings w/ prototyping or test equipment? - Page 1
Forum section: electronics / general

author: nez
author_rank: Regular Contributor
timestamp: May 15, 2024, 09:40:29 am
content: I'm visiting a friend in Shenzhen for a week, and I thought I'd browse around the electronics market area. I found countless shops and buildings with consumer electronics, ICs, phone/watch accesories and parts, security products, LEDs, and other things. The scale of the place is amazing!However, so far I didn't encounter any area or store that had prototyping tools/supplies or test equipment (e.g. scopes, VNAs, etc.).It's my first time to visit so I may have a lot of misconceptions.The closest I found were shops that specialized in electronics repair tools (soldering/hot air stations, inspection scopes/cameras, and handheld DMMs). I also saw a few small sales counters with things relating to single board computer platforms.Any suggestions for test equipment? There are too many buildings to explore casually in my available time. Maybe this kind of thing is generally online order only.

author: thm_w
author_rank: Super Contributor
timestamp: May 15, 2024, 09:24:46 pm
content: Don't know if this guide is available anywhere online:https://www.crowdsupply.com/machinery-enchantress/the-new-essential-guide-to-electronics-in-shenzhenThe older version is here:https://bunniefoo.com/bunnie/essential/essential-guide-shenzhen-web.pdfDid you ask anyone at SEG Electronics Market if you went there?

author: Hedy
author_rank: Newbie
timestamp: May 16, 2024, 10:05:35 am
content: I actually have a shop in Huaqiangbei where I sell chips and other electronic goodies. It’s pretty cool that you’re exploring the area! If you need some pointers or want to check out some gear, feel free to swing by my shop or hit me up. I’d love to help a fellow electronics enthusiast out!

author: nez
author_rank: Regular Contributor
timestamp: May 17, 2024, 06:59:09 am
content: Quote from: thm_w on May 15, 2024, 09:24:46 pmThanks for the guide links, although it is beyond my personal scope it’s a good reference!I asked around at a few places in the area but they weren’t sure (or the translation app results confused them). I don’t think I asked in SEG, if I remember right.Quote from: Hedy on May 16, 2024, 10:05:35 amThanks for the offer, I’ll send a direct message for the details and stop by when I have the chance!
Measurement of temperature on/besides Mosfet  - Page 1
Forum section: electronics / general

author: eTobey
author_rank: Super Contributor
timestamp: May 12, 2024, 06:09:52 pm
content: Hi,i am wondering where i can get the most accurate measurement for the temperature of the mosfet. Besides (B) or on the case (A)?There are 4 layers of 2 oz copper and the vias go to the back side to a heatsink. There is much copper around, but not directly connected.

author: PwrElectronics
author_rank: Regular Contributor
timestamp: May 13, 2024, 06:18:59 pm
content: If the fet has an exposed case tab, what I have done in the past is solder a type "T" thermocouple to that tab. T thermocouple has 1 copper wire so it will take solder. Only do this if its not at a hazardous voltage. I have done this with 50VDC things OK but some thermocouple meters do not like if if the fet is high frequency PWM.If you go to the PCB, there is a temperature gradient through the solder and also the lateral heat flow. Temperature there will be cooler than at the case tab. But, the error is probably not a lot, depending...

author: Coordonnée_chromatique
author_rank: Frequent Contributor
timestamp: May 13, 2024, 06:37:21 pm
content: Hello, this is perhaps stupid, but could you tell why it is impossible to use the internal diode of a mosfet to track the die temperature ?

author: tom66
author_rank: Super Contributor
timestamp: May 13, 2024, 08:25:51 pm
content: You can't use the internal diode normally, as the diode doesn't conduct unless the MOSFET is reverse biased. Whilst it would be possible to design a circuit that allowed the diode to be biased in reverse to test the diode forward voltage and measure temperature it would involve numerous additional parts to do so, hardly worth it.However, you can use the RDS(on) change with temperature, provided you know the current you can back-calculate for temperature against a lookup table. This requires a current sensor or a load with a known constant load characteristic.

author: eTobey
author_rank: Super Contributor
timestamp: May 13, 2024, 09:08:40 pm
content: Since i put some redundant current sensors in, this would be an interesting thing to achieve. But i would have to calibrate this.I have looked at some thermal images. It would be then more accurate, to measure it on the case. But only if it does not have leads that are to big.

author: PwrElectronics
author_rank: Regular Contributor
timestamp: May 13, 2024, 11:56:51 pm
content: At work, we usually give a thin coat of flat white paint (I have used black but our tech lab said white is better) over the board to improve the emissivity when using a thermal camera. Especially if there are reflective metal surfaces.

author: thm_w
author_rank: Super Contributor
timestamp: May 14, 2024, 12:53:34 am
content: Quote from: PwrElectronics on May 13, 2024, 11:56:51 pmBlack paint has better emissivity (0.94 vs 0.84) but maybe they are worried about improving the thermals of the test board, or have a camera thats already calibrated to 0.84.https://www.thermoworks.com/emissivity-table/If OP had a thermal camera I suspected they'd already be using it.
Digikey asks for "What is your physical address for your file?" - Page 1
Forum section: electronics / general

author: terrance
author_rank: Contributor
timestamp: April 29, 2024, 08:05:34 pm
content: Hi,I ordered some parts on digikey. Then they sent an email asking the question. What even does "your physical address for your file" mean?

author: thm_w
author_rank: Super Contributor
timestamp: April 29, 2024, 09:02:59 pm
content: Probably just want your business or home address.Why not just respond to them instead of posting here?

author: terrance
author_rank: Contributor
timestamp: April 29, 2024, 09:19:12 pm
content: When I ordered something I already filled in my addresses ...

author: SmallCog
author_rank: Frequent Contributor
timestamp: April 29, 2024, 10:28:54 pm
content: They likely have fields for your business address as well as your delivery address in their system and one of these fields is blank so they've asked you for some more information.These addresses may well be the same place for you, but for others the businesses registered address may be different from the facility where the parts are to be delivered.Some large businesses may well get parts delivered to lots of different facilities/offices/workshops etc.

author: Psi
author_rank: Super Contributor
timestamp: April 29, 2024, 11:37:08 pm
content: They recently changed their system with regard to addresses.Previously i could select my shipping address from a list but i always had to manually type out the billing address every time i did an order.'(billing addr is my home addr but i always get stuff shipped to work office)But last time i placed an order that issue was fixed, it just knew my billing address for once.So its probably part of that change that caused them to ask you for an address.

author: SiliconWizard
author_rank: Super Contributor
timestamp: April 29, 2024, 11:47:17 pm
content: Quote from: Psi on April 29, 2024, 11:37:08 pmProbably, but the sentence still sounds a bit odd.

author: ejeffrey
author_rank: Super Contributor
timestamp: April 30, 2024, 03:52:52 am
content: Yeah, it's probably an email sent by an actual human who was being sloppy or made a mistake.Reply and ask which address they need, billing or shipping.

author: edpalmer42
author_rank: Super Contributor
timestamp: April 30, 2024, 04:42:03 am
content: Maybe they're dealing with new tax or security regulations that insist on a physical location rather than a billing or shipping address which might not be the physical address of the person or business. e.g. the billing address could be a P.O. box while the shipping address could be a remailer or a P.O. Box.

author: Halcyon
author_rank: Unknown
timestamp: April 30, 2024, 01:02:25 pm
content: My view is, they don't need to know except for delivery purposes. (Unless you have a credit account.)

author: terrance
author_rank: Contributor
timestamp: May 09, 2024, 09:56:29 pm
content: Thanks so much for all your thoughts, folks!I was using credit card, also filled in billing address.I just replied "...it the same as my shipping address...", and the business went smoothly.
salvaging a cheap bench grinder from off the street - Page 1
Forum section: electronics / general

author: jonovid
author_rank: Super Contributor
timestamp: May 09, 2024, 04:01:27 pm
content: after salvaging a cheap 150 watt AC bench grinder from off the street curbside rubbish that had a thin broken Zinc die cast base plate.I found it worked but the broken base problem was maybe caused by poor axle balance.after replacing the broken base plate with my own made up wooden base with rubber matting for its feet. -see imageit still had some vibration. also added a buffing wheel to one end of it. for aluminum polishing work.recessed all the bolt heads in to the green painted timber base.-see the image of the original bench grinder as sold with its thin Zinc die cast base.

author: jpanhalt
author_rank: Super Contributor
timestamp: May 09, 2024, 04:27:31 pm
content: Those tapered spindles are common for quick-change buffing and fine scratch (wire) wheels. I would be hesitant to use them with heavier grinding wheels. Nice job on the wood base. That's what I would have done with a hardwood like birch or maple. Cherry is also quite hard.Does it vibrate about the same with nothing attached? If so, are the bearings sleeve or ball/roller? Can they be replaced? Armatures can be balanced, but I have never tried doing that.

author: Gyro
author_rank: Super Contributor
timestamp: May 09, 2024, 04:36:23 pm
content: Wow, that's thin.You might find that you can address the vibration by re-centering the grinding wheel. You should find there's (should be) a little play on the spindle - it should never be a tight fit on the spindle. Whilst you have the off, put a screwdriver through center and gently tap the edge with thehandleof another one. If it doesn't ring like a bell, it's cracked and dangerous. Don't over-tighten the nut and ensure that the card shims are in place on both sides of the wheel.Ultimately the way to stop vibration caused by a grinding wheel it to use a Diamond wheel dresser on it. One like this but local...https://www.amazon.co.uk/Silverline-263215-Diamond-Wheel-Dresser/dp/B002QRSP3ONice repair.
1SS86 Hitachi Diodes Source? - Page 1
Forum section: electronics / general

author: W4PJB
author_rank: Regular Contributor
timestamp: May 08, 2024, 07:25:50 pm
content: I'm looking for some 1SS86 diodes to build some lectenna's. I'm told the Hitachi's are the best but are no longer in production.There seems to be a few sellers of these on the 'ol AliExpress, but I have only slightly more faith in getting genuine articles from AE than I do from Wish.Does anyone have experience buying these from AliExpress, or have a trustworthy source for these?I'd be open to other Schottky diodes as well, but from what I understand these are the most sensitive.

author: BrokenYugo
author_rank: Super Contributor
timestamp: May 08, 2024, 08:13:06 pm
content: Mouser or Digikey, LCSC for direct from China, you'll probably find through hole selection limited. 1N5711 might work.Assume cheap eBay/Amazon/Ali small signal diodes are all 1N4148.If you want sensitivity a high efficiency LED is probably equally important.
a program that sends a text file from China to Europe without getting blocked - Page 1
Forum section: electronics / general

author: cedric!
author_rank: Contributor
timestamp: May 05, 2024, 10:26:26 am
content: I have a PC in China that does a final test on a device in an assembly line. Each time the tests runs, a text file is created with the test results.I would like to automatically send this text file to a PC in Europe.Both PC's are running Windows.I have administrator rights on both PC's.What options are there that are not blocked by the great firewall of China?Can I setup a VPN between these two PC's? Do I need to make the VPN traffic look like something else?Do need to resort to TOR or freenet?I found these options to connect to tor in china:https://support.torproject.org/censorship/connecting-from-china/

author: soldar
author_rank: Super Contributor
timestamp: May 05, 2024, 11:33:13 am
content: Quote from: cedric! on May 05, 2024, 10:26:26 amAre you serious? I send and receive text and other files daily to and from China.I think you might be imagining problems where there ain't.Have you tried? What was the problem?

author: SiliconWizard
author_rank: Super Contributor
timestamp: May 05, 2024, 11:00:00 pm
content: They don't block everything obviously, but they do have a pretty long blacklist.I suppose that depending on your ISP and/or whatever additional service you use, you may or may not hit a brickwall. Resorting to TOR looks like a bit overkill - is your problem getting blocked, or are you afraid of your data being surveilled?

author: tom66
author_rank: Super Contributor
timestamp: May 06, 2024, 09:30:15 pm
content: You can just make a HTTPS request to a server you operate. Secure, uninterceptable, and if you use a client and server that supports DNS-over-HTTPS then it is pretty much impervious to blocking (other than China just blocking all DNS-over-HTTPS stuff, which might happen eventually, but would be a big step.)

author: langwadt
author_rank: Super Contributor
timestamp: May 06, 2024, 10:38:35 pm
content: just send an email

author: S. Petrukhin
author_rank: Super Contributor
timestamp: May 07, 2024, 09:43:57 am
content: There are so many ways to transfer data.It depends on your means and knowledge.Having a compiler in service and knowing how to use it, you can transfer files using several protocols, starting from opening a socket and ending with sending an e-mail recommended above.Or database entries, ftp, etc.Are you ready to program or do you want to find a ready-made tool?
I need to find the male plug for this connector - Page 1
Forum section: electronics / general

author: firehopper
author_rank: Frequent Contributor
timestamp: March 08, 2018, 04:30:09 pm
content: its used in pride/curtis/quantum power chairs as the charging port/programming port.

author: ebastler
author_rank: Super Contributor
timestamp: March 08, 2018, 05:55:15 pm
content: Indicating the size of the connector might be helpful. Is it a DIN-sized diameter, or something larger? (I found a few high-current DIN connectors, but with 4 pins max.)

author: firehopper
author_rank: Frequent Contributor
timestamp: March 08, 2018, 06:02:26 pm
content: dang it, knew I forgot something, its actually xlr sized.

author: ebastler
author_rank: Super Contributor
timestamp: March 08, 2018, 06:40:22 pm
content: Hmm, that one is more elusive than I would have thought. I'm afraid my Google-fu is not strong enough -- plenty of military-style hybrid connector but none of them looks quite right. I'll keep my fingers crossed that someone finds this thread who has actually seen those connectors in the wild before!

author: firehopper
author_rank: Frequent Contributor
timestamp: March 09, 2018, 01:25:20 pm
content: found a cable with the connector I need.. yay!https://howlandtechnology.com/store/1313-cable-xlr.html

author: firehopper
author_rank: Frequent Contributor
timestamp: March 09, 2018, 03:06:09 pm
content: but yeah apparently its a propitary plug or something, really frustrating to try and find..

author: German_Engineer
author_rank: Newbie
timestamp: May 06, 2024, 05:34:49 pm
content: I had the same problem with a Pride Quantum Q-logic 3 wheelchair. The connector is an XLR plug with 3 pins (Mainly for audio applications). It has two additional pins with a smaller diameter for the CAN bus interface. The pins are at a non-standard position. I searched the catalogues of known XLR plug suppliers without success - this must be a custom design. In the end, I put together a standard 3-pin XLR plug and two wire ferrules (white, outer diameter 1.5mm) as shown in the pictures. Some patience with a key file and epoxy did the job. The pinout (CAN-H, CAN-L , GND) is also shown in the pictures.I figured out the CAN messages for the joystick and for the speed of the left and the right wheel (see attached DBC file and two screenshots from MATLAB CAN Explorer). I am interested in any information about other CAN messages or CANopen OD/EDS/DCF of this or similar wheelchairs with Curtis Instruments hardware to help a university project for automated driving functions. It would be great if you could point me to a forum dealing with such topics.
is this a linear CCD? - Page 1
Forum section: electronics / general

author: spam_4_tea
author_rank: Newbie
timestamp: May 12, 2024, 06:08:57 pm
content: Hey guysI am reverse engineering an optical scanning system (best in it field) - came across this device being used to measure height of an item (Lazer source, 600mm distance, 400mm active range, Plano-Convex lens + air gap + filter in front of CCD)Anyone else think this is a Linear CCD? - recognize the device?

author: switchabl
author_rank: Frequent Contributor
timestamp: May 13, 2024, 01:10:08 am
content: Hamamatsu linear CMOS sensor, I think:https://www.hamamatsu.com/us/en/product/optical-sensors/image-sensor/ccd-cmos-nmos-image-sensor/line-sensor/for-industry/S13131-1536.html

author: spam_4_tea
author_rank: Newbie
timestamp: May 13, 2024, 07:32:07 am
content: Thanks you switchabl! - you are spot on - can I buy you a virtual beer lol
Is there a meaning to colors on a transitor? - Page 1
Forum section: electronics / general

author: RAPo
author_rank: Super Contributor
timestamp: May 04, 2024, 12:06:47 pm
content: I've got a whole collection of (unclassified) transistors.I'll know that a dot on it can mean it is a matched pair.But I also have transistors with several colours.Do these colours have a meaning?

author: Psi
author_rank: Super Contributor
timestamp: May 04, 2024, 01:01:43 pm
content: Yes, its just the part number without the prefix, like 2N etc..Colors are the same numbering as resistor colors. So red red red red would be 2N2222 etc...https://www.instructables.com/From-Resistors-to-ICs-Color-Codes/

author: RAPo
author_rank: Super Contributor
timestamp: May 04, 2024, 01:33:56 pm
content: Ah, thanks. That makes the classification job easier. Topline color = first digit?

author: Benta
author_rank: Super Contributor
timestamp: May 04, 2024, 08:54:49 pm
content: Please show the other side of those transistors. The "colour-code" hypothesis is not really credible to me.

author: floobydust
author_rank: Super Contributor
timestamp: May 04, 2024, 08:58:42 pm
content: I know those coloured stripes as ranking for hFEor IDSS, not the actual part number.

author: RAPo
author_rank: Super Contributor
timestamp: May 05, 2024, 11:29:57 am
content: I think you are right. There are several A06's but they have different colours

author: RAPo
author_rank: Super Contributor
timestamp: May 05, 2024, 11:31:27 am
content: Do you have more info on which colour is used for which property?

author: madires
author_rank: Super Contributor
timestamp: May 05, 2024, 01:03:06 pm
content: There are also BJTs with a dab on top to indicate the hFE range.

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: May 05, 2024, 01:22:58 pm
content: Many transistors were sorted for some spec, this is the way they were marked.Whether they were marked by the transistor manufacturer or the company using them in manufacturing could be found out by asking the transistor manufacturer if possable, if not, I do not know of another way.Although not as common this process is still used today.Jeff

author: RoGeorge
author_rank: Super Contributor
timestamp: May 05, 2024, 01:32:05 pm
content: There was a time when Ge transistors where binned by beta, or by fT, and each category was a dot of different color.

author: Benta
author_rank: Super Contributor
timestamp: May 05, 2024, 08:41:13 pm
content: MPSA06... I remember those.You have two different things here:1: the thin horizontal stripes are production codes for lot/year/week whatever. Done by Motorola.2: the "colour blobs" can be anything, but certainly not OEM.

author: Kleinstein
author_rank: Super Contributor
timestamp: May 06, 2024, 09:13:44 am
content: Japanese JFETs (e.g. 2SK...) often come with IDSS grading via a color code, even with the same system used on different parts. With modern part the color may have changed to a letter code representing the color (e.g. R, O Y GR BL ) not just for ordering.
When browsing Youtube in private mode, did they get rid of the AutoPlay button? - Page 1
Forum section: electronics / general

author: BrianHG
author_rank: Super Contributor
timestamp: May 04, 2024, 02:33:14 pm
content: When browsing Youtube in private mode, did they get rid of the AutoPlay button?Yes, is my private browser, not logged into Youtube, the option is missing and the auto-play is forced on meaning if I stated a video and left the room for a few hours, youtube will play indefinitely eating up my precious MB/Month limit.

author: MK14
author_rank: Super Contributor
timestamp: May 04, 2024, 02:50:10 pm
content: No, I still get the auto play slider.I assume you know (IIRC) it (auto play slider) moved position, at some point, not that long ago, also it doesn't seem to appear, if your playing window is too small.

author: BrianHG
author_rank: Super Contributor
timestamp: May 04, 2024, 03:10:48 pm
content: I think it may just be a bug in my FireFox. I doubt Youtube is trying to push more non-stop ads to anyone who just left their computer alone..

author: MK14
author_rank: Super Contributor
timestamp: May 04, 2024, 03:24:11 pm
content: Actually, there does seem to be a problem.I found this, very recent (around 2 days old) thread:https://www.reddit.com/r/youtube/comments/1ci9xfo/youtube_autoplay_button_and_setting_is_gone/

author: SiliconWizard
author_rank: Super Contributor
timestamp: May 04, 2024, 11:08:57 pm
content: I've noticed YT tends to re-activate the autoplay on its own if you're not connected to a YT account.I've encountered this behavior on a tablet using Opera. But the button is still there.The fact the button doesn't appear may be a Firefox bug, but the fact YT handles the autoplay feature as they please when you're not logged in is nothing new, and in private mode (where cookies are normally not used?), things are usually "worse" regarding YT options. They give you default options as they see fit.

author: BrianHG
author_rank: Super Contributor
timestamp: May 05, 2024, 12:55:41 am
content: It's not that the default option is auto-play, I already know it is. It's that the button itself has vanished.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 05, 2024, 01:05:38 am
content: Have you made sure that autoplay is disabled in the browser settings?
HART Modem Texas Instruments DAC8742H is it suitable for new Design ? - Page 1
Forum section: electronics / general

author: Dingle
author_rank: Newbie
timestamp: May 02, 2024, 12:20:13 pm
content: HiMy name is Dingle ,works for a small electronics company in Manchester UK. We manufacture scinetific instruments for water industry.I am thinking of using Texas instruments DAC8742H Hart Modem chip into our existing 4-20ma current loop based on XTR116.It is meant to do that job, I bought their EVM kit from Farnell and evaluated it and suitable for the purpose.My question is the availabilty of TI chips through Farnell and RS in UK / Europe market. I don't see much TI chips in Farnell / RS , though many are avilable in Mouser / Digikey. It is the same case with DAC8742H. According to Texas Instruments it is a an active chip and they do reccomed it for new designs.Is Arrow.com being used my PCBmanufacturing/assembly people in UK/ Europe ?, they have facility in London. Arrow is one of the distributors of TI chips in UK. TI being one of the giants and specialised chips comes from them mainly, but why Farnell / RS don't sell their stuff ?Let me know your expert opinion in this regard..Thank youDingle

author: tom66
author_rank: Super Contributor
timestamp: May 02, 2024, 12:58:36 pm
content: You will have little difficulty sourcing TI chips from DigiKey/Mouser/Arrow if you are using a CEM (contract electronics manufacturer) - they will deal with these guys every day.That said, TI are generally much less friendly to smaller companies than others, and this led a lot of engineers I know to design out their parts as they were too difficult to source during the semiconductor supply crisis. The situation has massively improved and most TI parts are available now, but there are still a fair number of bitter feelings left.TI also don't offer any product support any more directly to SMEs. You have to hope you can get it via your distributor, but this also often isn't available for SMEs.

author: Dingle
author_rank: Newbie
timestamp: May 02, 2024, 01:01:30 pm
content: HiThanks for your quick response and appreciate your time.kind RegardsDingle

author: nctnico
author_rank: Super Contributor
timestamp: May 02, 2024, 03:09:45 pm
content: Quote from: tom66 on May 02, 2024, 12:58:36 pmRest assured that TI availability will be non-existent when the next crisis hits. TI does make create parts with good documentation, but part availability is frugal at best.

author: tom66
author_rank: Super Contributor
timestamp: May 02, 2024, 03:18:29 pm
content: Quote from: nctnico on May 02, 2024, 03:09:45 pmFor sure, we respun several products during the shortage and went for smaller companies where we could maintain direct contact with the factory/design labs and they could work with us on getting smaller quantities of parts on an adhoc basis. Most TI parts in our designs have been removed now. TI doesn't care about the small guy -- so I don't care about TI.
How does this stuff work? - Page 1
Forum section: electronics / general

author: amir.razzaqi
author_rank: Contributor
timestamp: April 30, 2024, 02:41:08 pm
content: HelloThe following pictures are related to the disassembled parts of the speaker inside the handset of an old desktop phone (Belgacom maestro 350)The diaphragm of the speaker is made of two thin metal sheets that act as a 62nf capacitor.Behind the speaker diaphragm, there is a coil (with gap) that one pins common with diaphragm first pin and the other pin of coil connected to second pin of diaphragm trough a 1K8 resistor.Does anyone know how this speaker works?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 30, 2024, 02:52:31 pm
content: Piezo disc I guess?I suppose the coil would be loading, compensation for the disc capacitance, then. I mean, you have the parts in front of you, you can trace the circuit -- then measure the coil, and see what the impedance of the whole thing is at audio frequencies.POTS was 600 ohm, wasn't it? Should have a peak or valley impedance around that, in the phone range (500-3000 Hz).Tim

author: Andy Watson
author_rank: Super Contributor
timestamp: April 30, 2024, 03:08:07 pm
content: My guess would be that the 62nF disc is the piezo "speaker" - producing sound. The coil is probably there to be used with hearing-aids which have an induction coupling option.

author: SiliconWizard
author_rank: Super Contributor
timestamp: April 30, 2024, 09:19:14 pm
content: Quote from: Andy Watson on April 30, 2024, 03:08:07 pmYes.
How George Hotz Hack iPhone (the Hillary behind it?) - Page 1
Forum section: electronics / general

author: Mechatrommer
author_rank: Super Contributor
timestamp: May 04, 2024, 12:30:18 pm
content: while killing time, it usually started with some random youtube on my channel wall... what was meant only took couple of minutes can turn into couple of hoursit started with youtube title "Sony Attacked Anonymous And Immediately Regretted it" YT id: 66A4zcJaPLk... and then came the name George Hotz, clueless about who he is (yeah you can say i'm living in a cave), so the google investigation started, after reading some links i thought wow this guy could be the 2nd Kevin Mitnick! so then trying to google how this "geniusity", his 1st hack that made his famous is exactly this thread's topic and what i typed in google hunt (excluding whats inside the bracket)... so the politics behind it revealed (including Elon Musk's)...Reminder that geohot wasn't the first person to jailbreak an iPhoneif its true, then its quite hilarious as equally quite typical (we usually rely on the works of others) except he's quite lucky he started too young than most of us... probably his father bought him a good PC and he was living in a conducive hacking environment.another thing is OpenPilot the only post mentioning his name in this forum is thishttps://www.eevblog.com/forum/beginners/non-reprogrammable-gate-array-as-aposed-to-field-reprogrammable-gate-array/msg3914087/#msg3914087(this thread will be the second i guess) so his name is credited to this great self driving software, but OpenPilot is based on OpenAI isnt it which is created by a bunch of pHD holders in IT, so not so much wonder there, you and i can probably make some script on top of OpenAI and create something wonderful too right? given enough time and courage...with all this mumbling, its not actually my point.. my point actually is.. then i look up in google if there is any picture of his room probably i can get some idea how he worked on hacking the iphone, i cant get any from google, but it turned out the picture is available (although he is a little bit older in the picture) in the first video i mentioned above with the id (minute 4:51)... i thoughtWHAT?! NO OSCILLOSCOPE?!how easy it is to hack iphone IC's communication protocol without a scope? just some fancy boxes and monitor, and some retro/vintage AC/fan unit at behind and whats that next to it? a nitrogen tank? probably the real persons who actually did the real work on jailbreaking the iphone, ps3 or samsung android are those the unsung heroes living under the rock with some power line wires poking in... ymmv.so here it is, few hours wasted.... cheers.
JWST Takes a new photo of the horse head nebula - Page 1
Forum section: electronics / general

author: JustMeHere
author_rank: Frequent Contributor
timestamp: April 30, 2024, 08:31:36 pm
content: Main Article:https://science.nasa.gov/missions/webb/webb-captures-top-of-iconic-horsehead-nebula-in-unprecedented-detail/The magnification of this thing over the Hubble is damn impressive.https://science.nasa.gov/wp-content/uploads/2024/04/webb-miri-stsci-01hwdbrbh7r86c2m8n7kqaz8jr.png?w=2560&format=webpFull Rez photos:https://science.nasa.gov/wp-content/uploads/2024/04/webb-miri-stsci-01hwdbrbh7r86c2m8n7kqaz8jr.png?w=2560&format=webpWrong linkhttps://webbtelescope.org/contents/media/images/2024/119/01HV4BAFBCNVV1VFQ4XMASPGV9?news=true

author: Sal Ammoniac
author_rank: Super Contributor
timestamp: April 30, 2024, 08:59:33 pm
content: Amazing how many galaxies are visible in this image!

author: BrianHG
author_rank: Super Contributor
timestamp: May 01, 2024, 12:44:24 am
content: The full res images linked above are false, low-res and the MIRI ones. This is the true Webb NIRCam image link where you get the true full res:https://stsci-opo.org/STScI-01HV4CG0EACM1MC07E10X19KNX.pngSo be warned, it's 20mb.Source page:https://webbtelescope.org/contents/media/images/2024/119/01HV4BAFBCNVV1VFQ4XMASPGV9?news=true

author: JustMeHere
author_rank: Frequent Contributor
timestamp: May 01, 2024, 01:39:21 am
content: Quote from: BrianHG on May 01, 2024, 12:44:24 amYeah, whoops the last link is wrong...edited

author: JustMeHere
author_rank: Frequent Contributor
timestamp: May 01, 2024, 01:43:29 am
content: Quote from: Sal Ammoniac on April 30, 2024, 08:59:33 pmI can only speculate at the field of vision in the NIRI cam. Probably smaller than a pin head with an outstretched arm. Hubble images are, supposedly, the size of half a thumb nail at arm's length.

author: JustMeHere
author_rank: Frequent Contributor
timestamp: May 01, 2024, 01:54:14 am
content: Quote from: JustMeHere on May 01, 2024, 01:43:29 amJust looked it up....it has 2 x 2.2^2 arc minute cameras. The moon is about 30.

author: Halcyon
author_rank: Unknown
timestamp: May 03, 2024, 05:25:14 am
content: Stunning.Shots like that make me forget about all the fuckwits in the world for just a short moment.

author: Gyro
author_rank: Super Contributor
timestamp: May 03, 2024, 01:58:03 pm
content: Quote from: Halcyon on May 03, 2024, 05:25:14 amIt also brings a sense of reality to how insignificant they, and the rest of us, are in the 'grand scheme'.
Keychain bling, solder failure - Page 1
Forum section: electronics / general

author: joeqsmith
author_rank: Super Contributor
timestamp: April 28, 2024, 09:02:11 pm
content: I cut out some brass to make a custom keychain using an FPGA that I had used. These were well over $1000 back then and I had reballed this part twice before scrapping it. It's looking pretty rough now.https://www.ebay.com/itm/223223126383
The strange case of phase angles - Page 1
Forum section: electronics / general

author: ballsystemlord
author_rank: Frequent Contributor
timestamp: April 27, 2024, 04:21:58 am
content: Hello,I was doing some practice problems in my textbook and came upon a parallel RLC circuit. I calculated the phase angle using the impedance but my value differed from the answer key.Puzzled, I tried obtaining it from the amperage and power vectors successfully. I tried reviewing my math, but can't figure out why my impedance vector doesn't yield the same result as the amperage and power ones. Which is correct? I thought I could try and build a circuit to test this, but the fact that this is a textbook circuit makes it unrealistic so I can't make one.Attached are images of the problem, my calculator with results, and the answer key.So, what's the correct phase angle? Why do the impedance and amperage/power vectors differ in their angles?Thanks!

author: strawberry
author_rank: Super Contributor
timestamp: April 27, 2024, 08:44:45 am
content: simulate in Qspice

author: ballsystemlord
author_rank: Frequent Contributor
timestamp: April 27, 2024, 11:45:44 am
content: Quote from: strawberry on April 27, 2024, 08:44:45 amLearning Qspice is in my next book. But I could wait.EDIT: So far, I've done all calculations for all circuits by hand with a calculator, pen, and pencil.

author: Andy Watson
author_rank: Super Contributor
timestamp: April 27, 2024, 12:54:55 pm
content: The impedance of the capacitor should be combined with the impedance of the inductorin parallel; you appear to have combined them in series.

author: tooki
author_rank: Super Contributor
timestamp: April 27, 2024, 02:39:20 pm
content: And what that means is that to solve it trigonometrically, you can’t use the impedance (vector addition of resistance and reactance), but rather the admittance (vector addition of conductance and susceptance).As an aside: as someone who sucks at trigonometry, I just use my calculator’s ability to work with polar complex numbers. So calculating IT, for example, I just type:0.02 + 0.008∠-90 + 0.01571∠90and get0.02143∠21.1.

author: sicco
author_rank: Regular Contributor
timestamp: April 28, 2024, 05:49:43 am
content: The voltage source has an output impedance of zero ohms. It thus dictates a voltage on both the R, the L and the C. No matter what the values are for R, L or C. So no way that L, C, or R can ‘see’ each-other and form a LC resonator or so.The phase angle from voltage to current through each component leg is zero for R, 90 and -90 for L and C. The current from the source is the sum of I_R, I_C and I_R. So subtract L and C currents because they are 180 deg apart. Then atan the imag and real. So something like atan((I_L - I_C) /I_R) for the phase difference from V_source to I_source.
Philips Technical Review and index - Page 1
Forum section: electronics / general

author: Circlotron
author_rank: Super Contributor
timestamp: June 10, 2018, 11:20:32 am
content: Includes a list of ~1900 individual download urls you can put into your favourite download manager.

author: Circlotron
author_rank: Super Contributor
timestamp: June 10, 2018, 11:23:27 am
content: next

author: Circlotron
author_rank: Super Contributor
timestamp: June 10, 2018, 11:24:03 am
content: next

author: Circlotron
author_rank: Super Contributor
timestamp: June 10, 2018, 11:24:52 am
content: next

author: AlfBaz
author_rank: Super Contributor
timestamp: June 19, 2018, 01:41:02 pm
content: Just finished downloading all 1948 pdf files spanning from 1936 to 1988. What an eclectic mix of articles!Was just thinking an index for all these articles would be good. Searched for this thread to thank you again and I forgot that you posted index files as well

author: LaserSteve
author_rank: Super Contributor
timestamp: June 19, 2018, 08:30:54 pm
content: Thanks Again,Wonderful reading...Steve

author: cat87
author_rank: Regular Contributor
timestamp: June 20, 2018, 03:00:18 pm
content: Thanks. This is awesome.I visited the Philips Museum in Eindhoven a couple of weeks ago. The guys at Philips really were doing some cutting-edge stuff back in the day. This is another confirmation

author: Bill_at_PEARL
author_rank: Newbie
timestamp: June 03, 2019, 04:10:59 pm
content: Hello:About mid-May 2019 I visited this linkhttp://www.extra.research.philips.com/hera/people/aarts/_Philips%20Bound%20Archive/and pulled down a couple of items and going back on June 1st found the archive no longer there. I dug all over Philips, finally going to the WayBack where it says it's a blocked URL.If you could provide me with a link to your downloads, if there is one, or if you could provide the lot on a DVD (for which I'll pay) I'd host of my sitewww.pearl-hifi.comwhere >10,000 documents are available.Thank youBill

author: Bill_at_PEARL
author_rank: Newbie
timestamp: June 04, 2019, 03:01:30 am
content: With thanks for the off-list help, I now have the lot upped here:https://www.pearl-hifi.com/06_Lit_Archive/02_PEARL_Arch/Vol_16/Sec_53/Philips_Tech_Review/with the index reworked and at the very bottom of the directory listing. Over the next while I'll OCR the lot, re-up, and advise.There were several other directories, now vanished, that contained the full issues and the supplement issues all complete with covers etc. Did anyone score those ? ?Finally for the moment: is there a way to crater that yappy string of stupid emoticons that live atop of the message composition box; bloody distracting nonsense that reminds me of all those 1973 web pages we love to hateBest,Bill

author: andymok
author_rank: Contributor
timestamp: April 28, 2024, 04:31:11 am
content: Hi Bill, Thank you for hosting the Philips Technical Review. I was researching the fundamentals of CD-DA for quite some years, your collections helps a lot. Would you consider hosting them in archive.org, or would you mind if someone upload them?Thank you so much!
Looking for reverse osmosis with less than 25% waste  - Page 1
Forum section: electronics / general

author: Miyuki
author_rank: Frequent Contributor
timestamp: April 26, 2024, 06:53:09 pm
content: Are there any people with knowledge about reverse osmosis?I know some industry-scale systems can do this. But I want it with a small (medium) system with a rate of demineralized water of about 1 l/min.It will be fed with relatively highly mineralized ground water (plenty of Mg and Ca). And I do not like to throw plenty of water to waste.Do any of you have some experience with it?

author: thm_w
author_rank: Super Contributor
timestamp: April 26, 2024, 09:27:32 pm
content: From what I read, typical system wastes 70-90% of the water. So 25% waste would be incredibly hopeful.Is it necessary to remove the minerals?https://www.reddit.com/r/WaterTreatment/comments/iiatn5/zero_waste_reverse_osmosis_system/

author: strawberry
author_rank: Super Contributor
timestamp: April 26, 2024, 10:10:43 pm
content: to collect Mg and Ca much faster use two membranes and separate ore with compressed air at the same time cleaning memrane

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 27, 2024, 02:25:03 am
content: Drinking water is a small part of residential water use. Just use the "waste" water for other stuff?

author: m k
author_rank: Super Contributor
timestamp: April 27, 2024, 07:45:14 am
content: How much per day?You can always recycle it and hope that your tank is concentrating the heavy stuff.Shaping the tank and creating a vortex in it may help.You must also measure what you get so few more sensors are probably acceptable.E,If output is not enough you have two possibilities, more power or less recycling.Industry usually has no space problems, so they use reservoirs, if possible.You can also cascade the process, but since it's a forced operation you need more pumps.Measuring apparatus can be just one that is selected between different membranes, if final quality is not absolute.After process has started it is very stable, if recycling is only partial.Measuring apparatus can of course adjust the flow constantly also, if needed.The scale of expenses is probably few thousands, that's many qubes of raw water, but only "a drop" if need is constant.
EEPROM Marking codes - Page 1
Forum section: electronics / general

author: zesti
author_rank: Newbie
timestamp: April 22, 2024, 10:42:48 am
content: Hi all,New to this web site. I'm eltronics repair business and playing also with eeproms. Now I cam accross eeproms with starnge marking codes. And its hard to find them online. So need help, if any one could help out, like this eeprom with marking code AAY2F and Q935 below. Image is attached.Thanks.

author: wraper
author_rank: Unknown
timestamp: April 22, 2024, 10:52:24 am
content: image is broken.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 22, 2024, 12:21:46 pm
content: File size shows as 0KB, something's wrong!

author: zesti
author_rank: Newbie
timestamp: April 22, 2024, 12:51:57 pm
content: Sorry for attachment. I think I unplugged my mobile while tranferring. Thanks for notifying.

author: amyk
author_rank: Super Contributor
timestamp: April 23, 2024, 02:00:40 am
content: How sure are you that it's an EEPROM?

author: zesti
author_rank: Newbie
timestamp: April 23, 2024, 06:49:25 am
content: Quote from: amyk on April 23, 2024, 02:00:40 amThat's on an HP printer drum unit life counter PCB.

author: thm_w
author_rank: Super Contributor
timestamp: April 24, 2024, 08:31:54 pm
content: If it can't be found online, most likely its a custom part number chosen by HP. Since they order mass amounts of these.What you could do is connect to it with an eeprom programmer and try to detect what IC it is. Some have that functionality. Or map out the pinout and choose a similar part that matches up, then up the size until you start seeing the data loop and repeat.I don't know if this is relevant:https://h30434.www3.hp.com/psg/attachments/psg/Printing/2868898/1/111reset.pdf

author: DavidAlfa
author_rank: Super Contributor
timestamp: April 24, 2024, 08:46:20 pm
content: Probably custom so you can't simply plug it to a CH341 and reset it.

author: zesti
author_rank: Newbie
timestamp: April 25, 2024, 09:23:57 am
content: Yes , I was thinking the same. Will try and let you know. At least I can guess with pin layout of chip.The link in not relevent, thanks anyways.
piano switch - Page 1
Forum section: electronics / general

author: vivi-d
author_rank: Regular Contributor
timestamp: April 29, 2024, 02:16:04 pm
content: Hi, I found this neat looking switch on digikey. I read the datasheet, but it is unclear whether this is a momentary switch or not.How can I tell? Does anyone know?It's part number CKN10346-ND on digikey.https://www.digikey.com/en/products/detail/c-k/BPA01B/2641381

author: reboots
author_rank: Regular Contributor
timestamp: April 29, 2024, 02:27:28 pm
content: This is an on-off switch, identical in function to a top-actuated DIP switch. The datasheet doesn't explicitly state that, but the listed typical applications are a clue: "Address switch for industrial controls" and "Logic switching for computers and peripherals" would not ordinarily use a momentary switch.Datasheets will call out "momentary" or "MOM" for a momentary switch. Another convention is to use parentheses to denote a momentary function. For example OFF-ON and OFF-(ON) would indicate two switch variants, with the latter being momentary.I have never seen a momentary switch of this type. The best I can suggest is a tactile pushbutton switch.

author: vivi-d
author_rank: Regular Contributor
timestamp: April 29, 2024, 03:00:03 pm
content: Thanks for the great explanationI'll watch for clues like that in the future.
product design and anonimous data collection - Page 1
Forum section: electronics / general

author: strawberry
author_rank: Super Contributor
timestamp: April 24, 2024, 08:58:49 pm
content: what happen if some company buy data from google ... and use data to find innovative product ideaswhen companies can make profile of some person by buying peaces of data..similarly as amazon does with its sellersfacebook hold all rights to all data appeared on websitedont know about emails legal stuffbut basically someone sells off its innovation for 1EURnot legal expert nor read all license agreements or terms of use
LinusTT gets to play with an industrial Lumafield CT Scanner... - Page 1
Forum section: electronics / general

author: BrianHG
author_rank: Super Contributor
timestamp: April 21, 2024, 07:47:42 pm
content: Have fun seeing inside electronic gizmos...

author: Jackster
author_rank: Frequent Contributor
timestamp: April 21, 2024, 09:43:17 pm
content: I got to see a demo of a Nikon one of these and it was amazing to see the layers of a 3D print. Such fine detail.Could see the tiny air gaps between the layers and the jitter of the 3D printer.

author: thm_w
author_rank: Super Contributor
timestamp: April 23, 2024, 08:48:19 pm
content: It was a good demo.$75k/year sounds cheap too, for a large company that wants to do a lot of reverse engineering or in depth QC testing. Just that the product has to be relatively small.Not sure if it resolution is capable of circuit board level reverse engineering though?