hybridfree/eevblog-posts huggingface dataset:
The precision one-milliohm short circuit - Page 1
Forum section: electronics / general

author: Vell
author_rank: Contributor
timestamp: May 30, 2019, 09:18:03 pm
content: This happened back in '89 or '90 when I was an electronic midwife, being the first to apply power to newly-assembled switchmode industrial amplifiers. Separate output circuits handled positive vs. negative-polarity outputs, as I recall.One day, a new one had wrongly scaled output, but only for one polarity. Each polarity had a one-milliohm, four-terminal current sense resistor, but the scale factor was off by just about two, exactly -- too high.After probing and measuring, I concluded that the sense resistor was half a milliohm; got and installed a replacement. Same story. Decided to do a four-terminal measurement (as I recall), and both original and replacement were one milliohm.Now, our PC vendor was not one of the best, and we had occasional shorts. Turned out that there was a one-milliohm short across the sense resistor, likely between the current pads. This short was within 3%, or less.

author: MagicSmoker
author_rank: Super Contributor
timestamp: May 30, 2019, 09:23:55 pm
content: Welcome to the forum, but do try to post in the appropriate area. This - and your other posts, actually - really belong in general chat.

author: Zero999
author_rank: Super Contributor
timestamp: May 31, 2019, 07:40:48 am
content: Interesting. I wonder how stable the short was.How much current was the shunt passing?

author: Vell
author_rank: Contributor
timestamp: June 02, 2019, 02:21:48 pm
content: How much current? Sorry, have forgotten, but maybe 5 A.

author: Zero999
author_rank: Super Contributor
timestamp: June 02, 2019, 04:28:14 pm
content: Quote from: Vell on June 02, 2019, 02:21:48 pmPresumably it was a current measuring resistor?5A would have been a voltage drop of only 5mV, across 1mR. I imagine the amplifier would have needed be low offset, probably a chopper stabilised op-amp.

author: Vell
author_rank: Contributor
timestamp: June 02, 2019, 07:07:06 pm
content: As I recall, the op amp was not particularly special. Board layout, though, was probably skilled.
Datasheet needed - Vishay Siliconix SSTP54 - Page 1
Forum section: electronics / general

author: Neomys Sapiens
author_rank: Super Contributor
timestamp: June 02, 2019, 05:55:00 pm
content: Does anyone habe the datasheet for the Vishay Siliconix SSTP54 SMD JFET?The usual sources are all coming up blank! Thanks in advance!
VW Working on Ways to Keep You From Vomiting in Autonomous Cars - Page 1
Forum section: electronics / general

author: Homer J Simpson
author_rank: Super Contributor
timestamp: May 30, 2019, 05:32:42 am
content: https://www.vwvortex.com/news/vw-working-ways-keep-vomiting-autonomous-cars/

author: ebastler
author_rank: Super Contributor
timestamp: May 30, 2019, 06:23:44 pm
content: Very befitting to publish this piece on a site named "VW Vortex".
I just invented a Solar garden :D  - Page 1
Forum section: electronics / general

author: Miyuki
author_rank: Frequent Contributor
timestamp: May 30, 2019, 08:19:01 am
content: I want to show you new break in solar energy.Look how garden is flourishing with solar panels.Everything growing at least 1000% faster and all garden life happily crawling around.Also panels are gently and naturally cleaned by pure and organic cat fur.Make every garden solar powered

author: windsmurf
author_rank: Frequent Contributor
timestamp: May 30, 2019, 08:27:05 am
content: How does that work?

author: Whales
author_rank: Super Contributor
timestamp: May 30, 2019, 08:32:17 am
content: That's ridiculously dangerous. Some of those weeds are already Lichtenberg shaped.

author: Whales
author_rank: Super Contributor
timestamp: May 30, 2019, 08:33:57 am
content: Quote from: windsmurf on May 30, 2019, 08:27:05 amMulti-cellular organisms.

author: Ampera
author_rank: Super Contributor
timestamp: May 30, 2019, 08:34:55 am
content: My parents lied, electricity really does grow on trees.

author: Red Squirrel
author_rank: Super Contributor
timestamp: May 30, 2019, 05:47:06 pm
content: Solar freaking garden!Still more viable than solar road ways.
Look inside of an IGT slot machine and function - Page 1
Forum section: electronics / general

author: darrellg
author_rank: Unknown
timestamp: May 29, 2019, 05:42:13 pm
content: It should be noted that IGT discontinued the S2000 model slot machine at least 15 years ago.

author: tooki
author_rank: Super Contributor
timestamp: May 31, 2019, 11:23:05 pm
content: Quote from: darrellg on May 29, 2019, 05:42:13 pmKinda like how the narrator mentioned it’s obsolete within the first 30 secs of the video?
[Poll] [Teardown] Which one should I film first? - Page 1
Forum section: electronics / general

author: blueskull
author_rank: Unknown
timestamp: May 05, 2019, 04:18:37 am
content: I filmed a video about my recently acquired PXI system, and I hope to restart making videos.However, the filmed version doesn't have in depth teardown of either, and I bet the folks here want to see more detailed teardowns.So I'm redoing the videos, and here comes the question: which one do you want to see first?I will film and edit on the order of poll result.I also have an VNA, and I'm sure that will score the most interest, but I'm not going to mess with RF voodoo, especially considering the fact that I know little about them.If I don't know where not to touch to not to break it, and I can't fix it, I'm not opening it. Sorry for that.

author: vk6zgo
author_rank: Super Contributor
timestamp: May 05, 2019, 04:44:01 am
content: Quote from: blueskull on May 05, 2019, 04:18:37 amJust be gentle with RF stuff, & you won't go far wrong!

author: TheSteve
author_rank: Unknown
timestamp: May 05, 2019, 05:02:53 am
content: You don't want to open the RF shields on your VNA. It likely wouldn't change much, but you'd probably never have the same confidence in it.

author: windsmurf
author_rank: Frequent Contributor
timestamp: May 05, 2019, 07:29:16 am
content: How about an intro video to the whole PXI/e infrastructure?

author: Brumby
author_rank: Unknown
timestamp: May 05, 2019, 08:33:34 am
content: Quote from: windsmurf on May 05, 2019, 07:29:16 amTHIS!Some of us have had sheltered lives and rolling straight into components of an infrastructure leaves us wondering how it is structured and the benefits/challenges it can deliver. The other options are for us to do our own homework - which will still lack direction - or to build up a picture from each video ... which will take time and we would miss out on the significance of some features from earlier videos.

author: nctnico
author_rank: Super Contributor
timestamp: May 06, 2019, 12:36:28 am
content: Quote from: blueskull on May 05, 2019, 04:46:22 amWhen it comes to RF stuff: don't open it unless you are really sure it is broken. The same goes for everything else. Don't take it apart if it isn't broken (if it ain't broken then don't ruin it).

author: virtualparticles
author_rank: Regular Contributor
timestamp: May 29, 2019, 06:52:53 pm
content: What VNA model do you have to tear down?
How to keep scope and other cables out of the way. - Page 1
Forum section: electronics / general

author: soldar
author_rank: Super Contributor
timestamp: May 28, 2019, 11:17:48 am
content: I find it a challenge to keep cables handy but out of the way. Sometimes they all tangle up and it takes a while to untangle the one I need.I usually have the scope and a few other instruments near the right side of the workbench so I can let the cables just hang down the side. This is quite convenient for the few cables I use most as they are always ready for use.Now I have moved my workbench next to a wall and have no space for the cables to hang although they could hang to the front but this gets them more in the way of my soldering iron, drawers, etc. I might move the workbench away from the wall a bit so I can recover that convenient space.Another thing I do is I have fitted most cables with wire hooks and I can hang them from a horizontal wire on the wall. This is also quite convenient.As a last resort I coil them and put them away in a box or drawer but this takes time and I can never find the one I am looking for.Any other ideas or opinions?

author: ajb
author_rank: Super Contributor
timestamp: May 28, 2019, 08:45:07 pm
content: If you've got some wall space (behind a door is a good, usually available spot), Pomona lead racks are nice.https://www.pomonaelectronics.com/products/dmm-test-leads-and-probes/test-lead-holdersThe blue (large) ones are good for most scope and meter probes as well as mains leads, the black (medium) ones for BNC/XLR, and the orange (small) for other banana/crocodile/USB leads.

author: soldar
author_rank: Super Contributor
timestamp: May 28, 2019, 11:03:37 pm
content: Quote from: ajb on May 28, 2019, 08:45:07 pmThanks, those look good. Behind a door is where I already have my wire where I hang cables from. Those holders look like they could go well there.Before I buy them I am going to consider if there is some easy way of building myself something similar, in metal or wood. Probably not easy.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 28, 2019, 11:59:07 pm
content: Quote from: soldar on May 28, 2019, 11:03:37 pmJust take a wood board and screw some blocks to it from the back to create the gaps. Although given how simple it is, there's probably quite a few cheap but good premade ones available.

author: soldar
author_rank: Super Contributor
timestamp: May 29, 2019, 12:27:50 am
content: That or take a flat piece of PVC and cut the slots. That allows slots of different sizes.
China weaponizing rare earths - Page 1
Forum section: electronics / general

author: Reckless
author_rank: Frequent Contributor
timestamp: May 29, 2019, 06:32:57 am
content: https://ca.finance.yahoo.com/amphtml/news/china-gears-weaponize-rare-earths-002041977.htmlIs this something that will affect silicon wafers or pcb manufacturing?

author: SMTech
author_rank: Frequent Contributor
timestamp: May 29, 2019, 08:44:44 am
content: Not so much semis as everything else I think, capacitors in particular.It has been a concern for a while, China has a pretty strong grip on this market to the extent that even where the raw materials are not under their control, the live processing facilities for them are Chinese. Other nations have these facilities but they can't run at a profit at the prices set by Chinas dominance and so are dormant.As the article points out this is a potent but fairly short term weapon, rare earths are not rare; if they use it too bluntly it can lose its potency but prices obviously would go up, and investing in these other plants is somewhat risky as China can always turn the tap back on and drown them.
Diode reverse bias leaking voltage issue - Page 1
Forum section: electronics / general

author: gkmaia
author_rank: Frequent Contributor
timestamp: May 29, 2019, 08:00:08 am
content: Got a switching diode that is allowing voltage to leak on reverse bias, but no current. Just voltage. Attached a video bellow.I tested several of these at 30V/30mA to find any defective one. This one leaks around 70mv and it is out an 100MHZ oscilloscope with a faulty sweep.The diode is a fast switch one and sits between the sweep gate and the inverting amp. Considering that: how a leakage like this could affect the performance of my faulty sweep?
When will a thermal imaging watch be available? - Page 1
Forum section: electronics / general

author: wadizuwaro
author_rank: Newbie
timestamp: May 28, 2019, 11:55:39 am
content: Just a free thought, it would be real cool and useful if we can have a watch similar to Detective Conan, which can help us see in thermal...

author: GlennSprigg
author_rank: Super Contributor
timestamp: May 28, 2019, 12:17:21 pm
content: I firmly believe that within say 20 years, we will have the availability of a 'chip' implant in the Brain.Want to do a mathematical calculation ?? Just THINK of it, and the answer is there !!!!(Let alone just wanting to know the bloody time !!)These current wrist watches for 'Gym-Junkies' will be like the 1st electronic 'Ping-Pong' device.Doctors will monitor your heart-rate, graphs & a myriad of other statistics remotely, any time.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 28, 2019, 12:35:59 pm
content: Shouldn't be too difficult to make one.
Search for flex PCB 700x700mm - Page 1
Forum section: electronics / general

author: generic_username
author_rank: Regular Contributor
timestamp: May 07, 2019, 02:58:17 pm
content: Hello everyone,I'm currently searching for a manufactor in europe/asia for a flex PCB with 700mm x 700mm which is kinda huge.I know of 1 manufactor in germany that can produce that but I want to compare prices to others, so far I couldn't find any.I really just need a flex pcb with copper on it no electronic parts on the flex.So if you know 1 or 2 manufactors that may can produce this, this would be much appreciated.cheers-.

author: qat
author_rank: Contributor
timestamp: May 07, 2019, 03:23:08 pm
content: I get all my PCBs from here:http://www.multek.se/index.php?page=homeThey can get you anything from cheap Chinese trash to space/military grade stuff. Might be on the more expensive side though.

author: Pitrsek
author_rank: Regular Contributor
timestamp: May 07, 2019, 09:49:11 pm
content: Here you go:https://www.trackwise.co.uk/https://www.pcb-tecnomec.com/index.html

author: generic_username
author_rank: Regular Contributor
timestamp: May 28, 2019, 06:44:09 am
content: A little late (sry btw) but Thank you
Prevent SCR latch on MAX1044 capacitor boost IC - Page 1
Forum section: electronics / general

author: Psi
author_rank: Super Contributor
timestamp: May 27, 2019, 05:42:01 am
content: In a product we have this MAX1044 circuit for voltage boost and every so often the chip fails.I saw one MAX1044 get quite hot.And i think i saw one fail and then recover back to normal once.After some probing i found this on pin 2 (CAP+ output). The ringing is pulling the pin 2V below ground.(EDIT this turned out to be bad grounding, it's actually more like 250mV below ground)It looks to me like it's at risk of SCR latchup? or latch down i guess in this case.SCR latch-up is not something i've had to deal with myself, so i thought i would ask here.Would you agree? and what solution do you recommend?I tried to put a 1N5819 diode from pin2 to GND to see if i could clamp it.It made a tiny improvement, maybe from 1.9V to 1.7V.I would have expected a 5819 to clamp it to ~0.4V so i'm not sure why it didn't?(EDIT: This will have been due to actual voltage being much lower)

author: Psi
author_rank: Super Contributor
timestamp: May 27, 2019, 06:02:41 am
content: I decided to double check things and probed it better using the ground spring instead of the ground clip.Most of that 2V was just bad grounding.There is a negative voltage but its more like 250mV.But i'm not sure if this is acceptable or not

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 27, 2019, 07:04:04 am
content: Shorted output will force the CAP+ pin very negative. No idea if that's the problem, but very likely it'll fuck things up when it happens.Could add schottky clamp diodes to the pin and see if it behaves.Also, put a big fat 100uF or more on the supply. Doesn't have to be adjacent, it can be elsewhere in the circuit, but it's probably going to need something somewhere.Tim

author: Psi
author_rank: Super Contributor
timestamp: May 28, 2019, 12:06:58 am
content: Good point Tim,I will add a diode permanently.You mean 100uF input cap? yeah, that's a good idea. Maybe the pulsed load is pulling the input lower than whats stored in the output caps

author: David Hess
author_rank: Super Contributor
timestamp: May 28, 2019, 04:13:05 am
content: This has been a known problem for 30 years on switched capacitor charge pump ICs which are not specifically designed to be immune and you identified it; SCR latchup is possible if a pin is pulled below ground or in the lessor case, it will not start because of minority carriers injected into the substrate.As I recall, the solution is to add an external schottky diode to ground to divert the current.Read some of the early switched capacitor charge pump datasheets from Linear Technology; they describe the problem and list some of the parts affected.
Atom Power - Page 1
Forum section: electronics / general

author: joeqsmith
author_rank: Super Contributor
timestamp: May 28, 2019, 02:40:42 am
content: https://www.atompower.com/QuoteOops, sorry I just killed your working after touching the wrong thing on my smart phone.QuoteIs clearing the 140 year hurdle another way of saying no UL cert?John Ward (YT channel) made a video on AFCI which I also found interesting. I'm not impressed with some of this new fancy technology that can't even do the one basic thing it was designed for.
Name of British YouTube Channel dealing with High Power Stuff - Page 1
Forum section: electronics / general

author: Glenn0010
author_rank: Regular Contributor
timestamp: May 23, 2019, 02:06:55 pm
content: There was this British YouTuber , I think his channel is quite old.Used to do electrical stuff in his house. Just purely electrical, no digital stuff. Used to play with varistors transformers and so on. I can distinctly remeber him burning stuff aswell. He also had classic British dry sarcasm and O think he mentioned he was getting a divorce in one of his videos.Can anyone remember the name of this YouTuber?

author: Psi
author_rank: Super Contributor
timestamp: May 23, 2019, 02:07:31 pm
content: photonicinduction would be my guesshttps://www.youtube.com/user/Photonvids

author: Glenn0010
author_rank: Regular Contributor
timestamp: May 23, 2019, 02:11:13 pm
content: It's totally him. That was quick. Thanks

author: Brumby
author_rank: Unknown
timestamp: May 24, 2019, 02:07:38 am
content: We know him well. He did have some marital problems - not with his lady, but with the British government.Fortunately, they seem to have been sorted.We believe he might be making new videos in the not-too-distant future. It will be good to see him back up and running.

author: EEVblog
author_rank: Unknown
timestamp: May 25, 2019, 05:33:33 am
content: Quote from: Brumby on May 24, 2019, 02:07:38 amYes, I posted a photo of his new backyard experiments a while back. He said he'll get back into videos soon-ish.

author: Towger
author_rank: Super Contributor
timestamp: May 25, 2019, 05:46:25 am
content: Quote from: Brumby on May 24, 2019, 02:07:38 amWife #1 dumped him:https://www.youtube.com/user/PhotonsWife

author: windsmurf
author_rank: Frequent Contributor
timestamp: May 25, 2019, 05:49:02 am
content: Quote from: Psi on May 23, 2019, 02:07:31 pmHe reminds me of FPS Russiahttps://youtu.be/dSp7CipN1pw

author: Arjunan M R
author_rank: Regular Contributor
timestamp: May 25, 2019, 05:54:58 am
content: I have also seen his video but it didn't look like he is british

author: amyk
author_rank: Super Contributor
timestamp: May 25, 2019, 06:07:41 pm
content: Quote from: Arjunan M R on May 25, 2019, 05:54:58 amThe UK has many different accents, maybe you just didn't recognise his.

author: KJDS
author_rank: Super Contributor
timestamp: May 27, 2019, 07:11:59 pm
content: The accent is somewhere between East End and Essex, though I'm sure it's not real.
what is this connector called, who makes them? - Page 1
Forum section: electronics / general

author: innkeeper
author_rank: Unknown
timestamp: May 26, 2019, 04:07:52 am
content: anyone know what is this connector called or who makes them?

author: Brumby
author_rank: Unknown
timestamp: May 26, 2019, 04:42:46 am
content: Looks like the IEC form factor - but withroundpins? Can't say I've come across this.Is it for mains power? What are the basic measurements?

author: Halcyon
author_rank: Unknown
timestamp: May 26, 2019, 04:46:55 am
content: It looks quite small but it's difficult to tell from the image. It reminds me of the old Dell laptop power connectors:

author: innkeeper
author_rank: Unknown
timestamp: May 26, 2019, 07:34:19 pm
content: it is small like the laptop connector for the dell above
looks like EEVblog logo? - Page 1
Forum section: electronics / general

author: mattxcoon
author_rank: Contributor
timestamp: May 25, 2019, 07:14:25 pm
content: I was watching an episode of Midsomer Murders recently (Murder on St. Malley's Day, Series 5 Episode 5, 2002), and a photo caught my eye because it reminded me of the EEVblog logo.Does anyone know what it is? I assume the similarity is a coincidence, or is there some cultural reference I don't get (being from the U.S.)?

author: Zbig
author_rank: Frequent Contributor
timestamp: May 25, 2019, 08:05:22 pm
content: Meh, just the typical "no photos!" gesture where the to-be-photo-subject reaches out to cover/force away the camera lens with their hand but only manages halfway before the actual photo is taken. Nothing to see here, you're reading too much into it.

author: Brumby
author_rank: Unknown
timestamp: May 26, 2019, 02:39:12 am
content: Yes. Quite a common "pose" from people who don't want their picture taken. It just looks like the "Dave hand" image - but I don't believe Dave was indicating "don't take my picture". His looks more like "DON'T do that!!!"

author: bitseeker
author_rank: Super Contributor
timestamp: May 26, 2019, 03:25:12 am
content: Just a coincidence, but amusing nonetheless.

author: Bud
author_rank: Super Contributor
timestamp: May 26, 2019, 03:28:57 am
content: Quote from: Brumby on May 26, 2019, 02:39:12 amIt always looked a staged photo to me. There is something unnatural in the pose.

author: Brumby
author_rank: Unknown
timestamp: May 26, 2019, 04:45:02 am
content: Quote from: Bud on May 26, 2019, 03:28:57 amI think if you could see a video showing the situation when it was taken, it would be less of a mystery.

author: windsmurf
author_rank: Frequent Contributor
timestamp: May 26, 2019, 07:09:18 am
content: Its the univeral "talk to the hand" jesture.https://youtu.be/_O-QqC9yM28
More Shifty Business From Kogan Australia. - Page 1
Forum section: electronics / general

author: Muttley Snickers
author_rank: Unknown
timestamp: May 23, 2019, 05:04:13 am
content: I just noticed a discussion on the OZ Bargain site regarding another instance of Kogan Australia engaging in questionable business practices and dodgy marketing campaigns. The Australian Competition and Consumer Commission (ACCC) have once again commenced legal proceedings against the company but previous fines for similar activity clearly hasn't been a deterrent.Disclaimer: I've never bought anything from Kogan and have absolutely no interest whatsoever in any of their products, marketing wank or lack of customer service.ACCC - Search - Koganhttps://www.accc.gov.au/site-search/koganOZ Bargain - Koganhttps://www.ozbargain.com.au/node/458583

author: wasyoungonce
author_rank: Frequent Contributor
timestamp: May 23, 2019, 05:59:15 am
content: Thanks MuttleyManu people buy one price only and there are many business ready to take advantage. He's always been dodgy I'm glad they are after him but suspect it'll be a small slap on the hand as usual.

author: aargee
author_rank: Frequent Contributor
timestamp: May 25, 2019, 11:55:32 am
content: Not too different from the Ebay sales when having x% off a number of sellers who then jack their prices to compensate.Apparently it's a learned tactic from our politicians and their promises.
NIST Team Demonstrates  Next-Generation Chip-Scale Atomic Clock - Page 1
Forum section: electronics / general

author: Homer J Simpson
author_rank: Super Contributor
timestamp: May 22, 2019, 03:05:52 am
content: https://www.nist.gov/news-events/news/2019/05/nist-team-demonstrates-heart-next-generation-chip-scale-atomic-clockResearch Articlehttps://www.osapublishing.org/optica/viewmedia.cfm?uri=optica-6-5-680&seq=0

author: GlennSprigg
author_rank: Super Contributor
timestamp: May 22, 2019, 10:30:01 am
content: Uhuhh... Uhuhh....Regular 8am alarm.... COFFEE !!!!!!!!!!(sorry)

author: apis
author_rank: Super Contributor
timestamp: May 22, 2019, 11:06:38 am
content: Nice. Now if only they would mass produce them and sell them for production cost + 20% or at least something remotely reasonable.

author: Tomorokoshi
author_rank: Super Contributor
timestamp: May 22, 2019, 05:18:25 pm
content: From theopticapaper:QuoteThat's 26 octaves above middle E!

author: coppercone2
author_rank: Super Contributor
timestamp: May 25, 2019, 01:20:49 am
content: I fee like if this clock is low power it will be some kind of game changer.
Soldering training - Page 1
Forum section: electronics / general

author: blueskull
author_rank: Unknown
timestamp: May 25, 2019, 08:10:36 am
content: Do you guys think an IPC soldering training can help me in any ways?----------------------------Background:1. I have good soldering skills. I can solder any package you can throw at me, down to 0201/0.35mm CSP, but I've never been introduced to proper IPC training, so basically I can get the jobs done, but not to an internationally accepted quality standard.2. I'm moving from US to China, and there I may hire people, and I may have to train them to do soldering properly. I will not hire technicians, and I will only hire university grads, or maybe masters grads, so I expect the technician skill level to be not very good.3. I work exclusively with lead free, ranging from SnBiAg, SAC305 to Sn100e.4. I need to learn PCB laminate repair and underfill/conformal coating removal, which I have no experience.--------------------------It seems like IPC7721/7722 fit my needs, and I may go to an additional BGA module.The question is, is this necessary? And if so, should I consider CIT over CIS?
Experience with Components mart, or where to get DSEP30-12CR? - Page 1
Forum section: electronics / general

author: daqq
author_rank: Super Contributor
timestamp: May 24, 2019, 06:01:42 am
content: Hi guys,I'm trying to get 10pcs of the DSEP30-12CR. No normal distributors have it in stock, nor will they have it within a reasonable time frame. The only distributors that have it in stock are the iffy ones.Do you have any experience with these fellows:https://www.components-mart.com/product/IXYS-Corporation/DSEP30-12CR.html? The price is very low (a high one would not be an issue either), so that's a red flag.Or, you wouldn't have a few DSEP30-12CR laying around that you'd like to sell? Or where can I get some?Thanks,David
Brand-New Kilogram Based on Quantum Physics - Page 1
Forum section: electronics / general

author: Homer J Simpson
author_rank: Super Contributor
timestamp: May 22, 2019, 02:04:26 am
content: https://www.space.com/new-kilogram.html

author: rs20
author_rank: Super Contributor
timestamp: May 22, 2019, 02:14:34 am
content: https://www.eevblog.com/forum/metrology/changing-to-the-2019-si-redefinitions-on-may-20/https://www.eevblog.com/forum/chat/the-method-used-to-redefine-the-kilogram-is-just-insane/

author: xrunner
author_rank: Super Contributor
timestamp: May 22, 2019, 02:16:36 am
content: Thanks to science, now my new 1 kg rolls of PLA for my 3D printer will be more precise!

author: dnwheeler
author_rank: Regular Contributor
timestamp: May 22, 2019, 09:08:51 pm
content: So, how do they use the new standard to verify another weight? With a physical standard, you can at least put them both on a balance.

author: xrunner
author_rank: Super Contributor
timestamp: May 22, 2019, 09:19:02 pm
content: Quote from: dnwheeler on May 22, 2019, 09:08:51 pmAs far as a pound it's just a matter of dividing a kg by a number -Quote

author: rs20
author_rank: Super Contributor
timestamp: May 24, 2019, 01:47:34 am
content: Quote from: dnwheeler on May 22, 2019, 09:08:51 pmPhysical artifacts will still be the way to transport the kg internationally. The difference is that while before, those artifacts were compared against a very carefully maintained hunk of platinum (the "International Prototype Kilogram") before, now they are measured (perhaps indirectly) against the Watt balance. So we could have every single physical artifact on the planet destroyed, but could bring back exactly the same kilogram as before as long as we remember the value for Planck's constant that we decided on: 6.62607015×10−34. In exactly the same way that the length of a metre used to be the length of a particular hunk of metal, but a while back we decided the speed of light to be, by definition, 299792458 m/s, so now instead we can just shine a laser and see how far it travels in 1/299792458 of a second (only conceptually, of course, it's not quite that simple!).The fact that I can define the second, metre and kilogram (not to mention volts and amps and watts etc) by simply giving you a piece of paper and a laboratory, instead of handing you hunks of metal that I hope haven't deteriorated or changed, is a great accomplishment.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 24, 2019, 02:31:07 am
content: The big problem with said hunks, is that they lose mass (e.g., abrasion, desorption..), AND they gain mass (e.g., dust and fingerprints, adsorption). This happens on the order of micrograms per year, IIRC. All the international standards have been drifting apart from each other independently, including the official standard kg itself (of course, since it was defined as the standard, we wouldn't say that it was varying, but, y'know).Tim
Replacing a small LiPo pack in a camera - Wiring question - Page 1
Forum section: electronics / general

author: Halcyon
author_rank: Unknown
timestamp: May 24, 2019, 02:12:52 am
content: I've ordered a replacement LiPo pack for my car dash cam as the original battery has swelled. The replacement battery has 3 leads.The third lead is yellow and marked with a 'T' on the battery PCB. I'm assuming this is some kind of temperature monitoring?It is safe just to connect the positive and negative leads to the dash cam, leaving off the third lead (there is nowhere to connect it)?Since the new battery has a small PCB, I assume this contains protection circuitry in addition to whatever charge management is being done by the dash cam itself.
Fusion 360 under Linux - Page 1
Forum section: electronics / general

author: Mick
author_rank: Unknown
timestamp: May 01, 2019, 03:49:53 am
content: Hi everyone, Not sure if this is interesting to anyone but I'll document my outcome here for anyone wanting to install Autodesk Fusion 360 under xUbuntu 18.04 and maybe other distros of Linux.PrerequisiteCode:curl https://dl.winehq.org/wine-builds/winehq.key -Osudo apt-key add winehq.keysudo apt-add-repository 'deb https://dl.winehq.org/wine-builds/ubuntu/ bionic main'sudo apt install --install-recommends winehq-stablesudo apt install --install-recommends winetrickswinetricks atmlib gdiplus msxml3 msxml6 vcrun2017 ie8 corefonts fontsmooth=rgb winhttp win7winetricks d3d11=disabledInstallationCode:curl dl.appstreaming.autodesk.com/production/installers/Fusion%20360%20Admin%20Install.exe -O7z x -osetup/ "Fusion%20360%20Admin%20Install.exe"curl -Lo setup/platform.py github.com/python/cpython/raw/3.5/Lib/platform.pysed -i 's/winver._platform_version or //' setup/platform.pywine setup/streamer.exe -p deploy -g -f log.txtOnce up and running select DirectX 9 for graphics driver in Fusion preferences and then re-enable d3d11 (DirectX 11) in winetricks.UpdatesSame as installation but flag an update in step 5.Code:wine setup/streamer.exe -p update -g -f log.txtEnjoy, MickRef:https://gist.github.com/probonopd/0fab254aa0b6fc371d8db641822bd530#gistcomment-2799597Keep Fusion 360 up to date with this scriptCode:#!/bin/bashWORKING_DIR=~/FUSION360INSTALL_FILE=Fusion-360-Admin-Install.exe#Make Working Directoryif [ ! -d $WORKING_DIR ]; thenmkdir $WORKING_DIRficd $WORKING_DIR#Download install fileif [ ! -f $INSTALL_FILE ]; thencurl \dl.appstreaming.autodesk.com/production/installers/Fusion%20360%20Admin%20Install.exe \-o $INSTALL_FILEfi#unZIPmkdir UNZIP7z x -oUNZIP $INSTALL_FILE# Patchcurl -Lo UNZIP/platform.py github.com/python/cpython/raw/3.5/Lib/platform.pysed -i 's/winver._platform_version or //' UNZIP/platform.py# Update (may need to wineserver -k once finished)wine UNZIP/streamer.exe -p update -g -f - --quiet# Clean uprm -r $WORKING_DIRexit 0IssuesWorkspace menu on main bar placement wrong (tested multi display systems only)Tool not flowing mouse but placement ok

author: Bicurico
author_rank: Super Contributor
timestamp: May 01, 2019, 09:23:25 am
content: Cool!

author: Mick
author_rank: Unknown
timestamp: May 23, 2019, 12:05:24 pm
content: Quick footnote, Have also installed Fusion on Debian stretch-current (9.9)Had to install using win10 compatibility layer then switch to win7, otherwise wrong library's get installed!!!Code:winetrick win10Code:winetricks win7
US warns of threat from Chinese drone companies - Page 1
Forum section: electronics / general

author: Homer J Simpson
author_rank: Super Contributor
timestamp: May 21, 2019, 08:05:22 pm
content: https://www.bbc.com/news/technology-48352271

author: Stray Electron
author_rank: Super Contributor
timestamp: May 21, 2019, 08:23:25 pm
content: So the US's concern isn't that the owners of the drones could misuse data from them but that the manufacturers will have data sent directly back to them and that they could misuse it. Interesting! But what about the Internet ready refrigerators, door locks, TVs and zillion other "Internet Ready" devices made in China and sold in the US? IIRC there's already been one stuff animal that was taken off of the market in the US after they were found to be "phoning home".

author: magic
author_rank: Super Contributor
timestamp: May 21, 2019, 11:00:05 pm
content: Quote from: Stray Electron on May 21, 2019, 08:23:25 pmSame problem with them in general and not just the Chinese ones.As for the reason why they are singling out drones, I think you have your answer here:QuoteQuoteGovernment doesn't like to share its data when it's spying

author: techman-001
author_rank: Frequent Contributor
timestamp: May 22, 2019, 08:27:35 am
content: Quote from: Stray Electron on May 21, 2019, 08:23:25 pmRemember that little security disaster a decade of so ago when govt spooks were giving away their sooper seekret locations simply by wearing fitness trackers and many of them jogged from home to work ?

author: GlennSprigg
author_rank: Super Contributor
timestamp: May 22, 2019, 10:24:34 am
content: Do 'Huawei' make 'drones' too !! ??Maybe the Chinese Government is WiFi monitoring our latest 'Pizza' deliveries Concept !!!!to take over with a 'Wok-In-A-Box' trial...

author: Kleinstein
author_rank: Super Contributor
timestamp: May 22, 2019, 12:42:03 pm
content: The security thread part could be only political the president does not have to ask congress.I have the feeling the thread is more from economic success, driving US drone companies out of the market, so the CIA may have to buy there small drone in China soon, or get poor US quality.
you don't turn this drive ON - Page 1
Forum section: electronics / general

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: May 21, 2019, 11:06:55 pm
content: you just don't turn it off

author: Nominal Animal
author_rank: Super Contributor
timestamp: May 22, 2019, 11:08:53 am
content: Needs a similar label below, reading 11.
LED display failure mode (vertical stripes) - Page 1
Forum section: electronics / general

author: Axk
author_rank: Regular Contributor
timestamp: May 21, 2019, 08:45:39 pm
content: See the photo.Is this a common failure mode?Why would this happen?

author: Axk
author_rank: Regular Contributor
timestamp: May 21, 2019, 09:30:30 pm
content: Just a bus stop display. Don't know if it is active low.Wonder why would the wires fail.

author: golden_labels
author_rank: Super Contributor
timestamp: May 21, 2019, 09:31:25 pm
content: Uhh, I have removed the post while Axk was writing. Here is the original content:QuoteI have no idea if it is active-low or -high. Just guessing, what could cause that.The wires/connections might be bad for various reasons. Bad soldering? Temperature stres causing something to break? Segments of the display seem to be physically damaged, so perhaps the same event caused wiring problems? Or, posibly, something is shorting due to water ingress, condensation or tin whiskers — though I can hardly see how would that cause the whole column to be affected without causing a short that would damage the controller (but possibly it is current-limited internally and can survive shorts).

author: ucanel
author_rank: Regular Contributor
timestamp: May 21, 2019, 10:31:20 pm
content: Could you add a short videoand which driver did they uselinsn or C80 or etc. are there any hubs(hub75) in the system?Did anyone changed anything about the Driver PC?Is there any physical damage water or by hit,could you show inside of it?It look very messy poorly designed from the look of it.

author: Axk
author_rank: Regular Contributor
timestamp: May 21, 2019, 10:36:59 pm
content: Physical damage could explain that.I didn't notice it was damaged.I can't open it and see what's inside.There are quite a lot of these throughout the city, this is the only damaged one that I saw.

author: Yansi
author_rank: Super Contributor
timestamp: May 21, 2019, 10:38:02 pm
content: As it is mostly from the top, I'd guess water ingress and damage.

author: ucanel
author_rank: Regular Contributor
timestamp: May 21, 2019, 11:20:45 pm
content: I thought you need to fix it.
Can flux be rejuvenated - Page 1
Forum section: electronics / general

author: jonovid
author_rank: Super Contributor
timestamp: May 21, 2019, 05:26:42 am
content: Can dried up rosin solder flux be rejuvenated?I find my 2 yr old rosin solder flux in a tub, it has more viscosity.drying out.

author: ataradov
author_rank: Super Contributor
timestamp: May 21, 2019, 05:53:45 am
content: When I was young we only had solid rosin, and we made flux paste by grinding it up and adding alcohol to it. It worked perfectly.But I'm not sure how alcohol may interact with whatever solvent is already there.

author: jonovid
author_rank: Super Contributor
timestamp: May 21, 2019, 06:05:23 am
content: here is, I need time to go in to ithttps://www.amplifiedparts.com/sites/default/files/associated_files/sds_-_s-crsf-r80-2_and_s-crsf-r80-8g.pdfthis is the flux I usebottom label is missing !

author: ataradov
author_rank: Super Contributor
timestamp: May 21, 2019, 06:20:58 am
content: Well, it looks like it uses thishttps://en.wikipedia.org/wiki/DEG_monobutyl_etheras a solvent. I'm no chemist, but I think it should work fine with IPA. Try on small quantity first. In the end flux is not a very expensive item, and it is worth a try.

author: newbrain
author_rank: Super Contributor
timestamp: May 21, 2019, 06:22:12 am
content: Yes it can!All you need is a flux capacitor...sorry, it was too rich an opportunity.

author: jesuscf
author_rank: Frequent Contributor
timestamp: May 21, 2019, 08:29:41 am
content: Quote from: ataradov on May 21, 2019, 05:53:45 amAbout a year or two ago, just for the fun of it and nothing else I 'made' some rosin. This is what I did: first I located some pine trees in my neighborhood, I think they are white pines. From them I collected both some dried up and fresh sap; this is easier if the pines have been recently pruned which was the case. Tip, look around on the ground, sometimes the sap collects there as well. I collected the sap along with whatever was stuck to it into an small plastic bag (I should had used disposable gloves!). At home I placed the content of the bag into a can and added about 250 ml of 99% isopropyl alcohol. I waited several days for the sap to dissolve steering the mix once in while. Then I filtered the liquid with a paper towel. I left the liquid outside in a small container for several days to let the alcohol evaporate. When it was solid I broke it into small pieces and melted it with a heat gun into a mold made with aluminum foil. I have used that rosin both in a violin bow and for soldering. It also smells great! I seem to have misplaced it, but when I find it, I should upload a picture.
No space in a PDF file? - Page 1
Forum section: electronics / general

author: nctnico
author_rank: Super Contributor
timestamp: May 18, 2019, 06:57:36 pm
content: I just spotted this text in a datasheet from Murata:This PDF data has only typical specifications because there is no space for detailed specifications.

author: ataradov
author_rank: Super Contributor
timestamp: May 18, 2019, 07:15:13 pm
content: I think it is a part of their lawyer approved template. That text is present on every Murata document, and even though it appears to be a footnote, it does not really apply to any specific parameters, it is just there.

author: Benta
author_rank: Super Contributor
timestamp: May 18, 2019, 10:13:01 pm
content: I disagree, it has nothing to do with legal/lawyer issues.It's a marketing issue in a positive sense.All suppliers need to get an idea of what to develop, design and produce for the market, and the only way is to ask the customers.For the big, direct customers, this is no problem. But how do you handle SMBs?The teaser "this datasheet is incomplete" is a way to get feedback from SMBs through callbacks asking for more info, and thus getting inputs for new products.

author: soldar
author_rank: Super Contributor
timestamp: May 19, 2019, 06:59:33 pm
content: QuoteWhatever the reason the wording is pretty bad. If they want prospect customers to contact them it would be better to say something likeQuote
CR2032 cheap source - Page 1
Forum section: electronics / general

author: PerranOak
author_rank: Frequent Contributor
timestamp: May 19, 2019, 11:50:51 am
content: Does anyone have a favoured source for cheap CR2032 batteries please?They're in everything so I need loads but I've had bad experiences with really cheapo ones not lasting five minutes.Cheers.

author: Psi
author_rank: Super Contributor
timestamp: May 19, 2019, 11:57:33 am
content: how cheap is cheap.Panasonic CR2032 are 24cents in 100 qty at digikey.I consider that pretty cheap and Panasonic is a good brandhttps://www.digikey.com/product-detail/en/panasonic-bsg/CR2032/P189-ND/31939

author: james_s
author_rank: Super Contributor
timestamp: May 19, 2019, 06:28:05 pm
content: I've bought a few random batches of them from DealExtreme in the past, never really had any trouble.

author: MosherIV
author_rank: Super Contributor
timestamp: May 19, 2019, 08:49:51 pm
content: I get some from Poundland. Only use them for non critical stuff though.So far no problems.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: May 19, 2019, 09:01:03 pm
content: You might want to edit your title as it appears that cheap is only one of your requirements.If you get creative you can find really cheap 2032s. The cheapest I ever found was by buying remaindered electronic candles after Halloween and removing the included 2032. As I recall those were about a nickel each with an LED and really low quality battery holder thrown in.I haven't noticed big differences in quality from various sources, though I haven't paid enough attention to really tell. My experience has been that quality of the battery holder, and quality of the equipment design (low peak and average current draw) has more effect on the life of these batteries than the battery quality. YMMV.

author: Bicurico
author_rank: Super Contributor
timestamp: May 19, 2019, 09:43:39 pm
content: I buy mine at Ikea...https://m2.ikea.com/pt/pt/p/plattboj-pilha-de-litio-80291156/Regards,Vitor

author: bob91343
author_rank: Super Contributor
timestamp: May 19, 2019, 10:06:09 pm
content: I just ask ebay to list them in price order and buy from China. I haven't had a problem so far, just a few cents per cell. I also bought battery holders, very cheap.China is an excellent source for me; I rarely have a problem. Or at least, any problems I do have are no worse than when I buy from so-called reputable sources. The down side, beside long wait time, is inability to inspect the product and see if it fits, etc. And should I ask a question, the person on the other end doesn't really have the ability to communicate well in English.

author: PerranOak
author_rank: Frequent Contributor
timestamp: May 21, 2019, 06:12:04 pm
content: Cheers all.Yes, I should have said "cheap and long lasting"!

author: tkamiya
author_rank: Super Contributor
timestamp: May 22, 2019, 05:51:15 pm
content: I buy in bulk from Amazon. Cheap ones are from third party vendors though. Results has been hit and miss. I test them with my battery tester.
Anyone with experience: AMI BIOS customization / AMIBCP ? - Page 1
Forum section: electronics / general

author: DDunfield
author_rank: Regular Contributor
timestamp: May 15, 2019, 05:30:39 pm
content: I'm trying to enable access to a "Primary Display" selection option in an AMI BIOS. Looking at it with AMIBCP it appears in an unnamed sub-menu which appears under the "Main" menu in the menu tree, however there does not appear to be an item to link to in within "Main".Having not done this before, it's not clear to me how to enable access to this menu. I've seen screenshots from users who have "unlocked" the same BIOS showing the "Primary Display" selection, so I'm pretty sure it can be done. Can anyone offer any insight?WHY: I was given a fairly nice MSI I7 laptop in which the NVIDIA GPU has failed. This is on a separate board and can be removed. The laptop works perfectly via the integrated Intel GPU ... except ... the fan goes to maximum and stays there shortly after power-on.Researching, I discovered that the fan is not controlled via the usual OS accessible PWM, but through a monitoring chip configured by BIOS .. there does not appear to be any other way to control or configure the fan. MSI defaulted the "Primary Display" option to the NVIDIA GPU and this causes the BIOS to configure it for monitoring. I'm told that if I can change "Primary Display" to the integrated GPU this will not occur and the fan will operate as it should. But MSI has disabled most of the "advanced" options in the BIOS including anything related to video configuration and hence the need to un-hide it.As changing the default value could lead to an unrecoverable situation, I'd like to enable access to the option so that I can change it, but leave the default in the configuration I know works.Any help would be appreciated.Dave

author: DDunfield
author_rank: Regular Contributor
timestamp: May 16, 2019, 06:23:39 pm
content: Follow-up in case anyone else has a similar problem and encounters this.Viewed in AMIBCP the "main" menu had a blank item at the very end.. I changed it to "USER" access and it appears in the BIOS as an unlabeled selection which takes me to the unnamed sub-menu that contains (among many others) the previously unavailable "Primary display" option. MSI defaulted this to "SC" which I'm guessing means the external GPU card. Changing it to "Auto" did not help (fan still 100%), however changing it to "IGFX" - meaning only the integrated graphics worked a treat! - nice and quiet now.Dave
Inside an electric vehicle battery. - Page 1
Forum section: electronics / general

author: G7PSK
author_rank: Super Contributor
timestamp: May 14, 2019, 09:31:03 pm
content: Came across this where he dismantles an electric vehicle battery from Mitsubishi, The cells appear to be large pouch type or in a rectangular cannister.https://youtu.be/mIDh3yjWKcg
1979 Cadillac Trip Computer - Tripmaster - Page 1
Forum section: electronics / general

author: alpher
author_rank: Frequent Contributor
timestamp: May 15, 2019, 01:50:54 am
content: I still prefer Eldorados, could never afford it then, and probably even now.Missed my chance.

author: floobydust
author_rank: Super Contributor
timestamp: May 16, 2019, 12:56:36 am
content: A $920 option in 1979 dollars... $3,238 today.GM was big into custom Motorola 6800's in those years.I wonder how they figured fuel quantity used. Modern cars have totalizers for injector pulse-width and I think fuel pressure/density as a correction.The Zemco ZT-1 aftermarket trip computer 1980's used an optical positive-displacement flow meter, I think it had rotating vanes inside.These cars are literally a chesterfield/sofa on wheels - the ride is so smooth, you don't even notice a pothole.