hybridfree/eevblog-posts huggingface dataset:
Big caps Rattle - Advice needed - Page 1
Forum section: electronics / general

author: ColdPower
author_rank: Contributor
timestamp: September 17, 2021, 12:35:44 pm
content: Hello everyone,it's been my understanding since forever, that if a cap rattles, this can't be good and I always would replace immediately. Have had hundreds of smaller snap-in rattlers replaced, but I just got a brand new Nichicon of series I haven't used before and it has a slight rattle from inside. Anyone used these and noticed this. Could that possibly be normal for them?

author: amyk
author_rank: Super Contributor
timestamp: September 17, 2021, 01:23:24 pm
content: That usually means the capacitor roll is smaller than the can. I would check capacitance and ESR, if it's normal then it might not be a problem.

author: madires
author_rank: Super Contributor
timestamp: September 17, 2021, 02:07:07 pm
content: Measuring is a good advise. Also check the voltage rating. Might be a fake.

author: ColdPower
author_rank: Contributor
timestamp: September 17, 2021, 04:08:59 pm
content: Thanks for the suggestions. The cap measures perfectly fine, but so do a whole box of few hundred old caps that I have, most of which rattle and measure okay. And for those I definitely know they shouldn't rattle when new. So I wouldn't rely on measurement alone, I'm more curious if that's at all possible to be normal for the type or indicates a problem, such as bad seal maybe. If anyone has the same or same type, would be great to share. Shame I only ordered one, so no base to compare.Oh, and I think it's safe to say it's not fake, it comes from DigiKey. Also the date code is 2051 which if I'm not wrong would make it just under an year old, so not a problem there either.

author: Gyro
author_rank: Super Contributor
timestamp: September 17, 2021, 06:02:41 pm
content: I think I'd probably open one up. Even if they aren't fake, rattling innards can't be good for reliability, particularly in an environment that would involve any degree of vibration.I'm sure it wasn't the manufacturer's intention that they would rattle.

author: ColdPower
author_rank: Contributor
timestamp: September 17, 2021, 06:15:19 pm
content: Quote from: Gyro on September 17, 2021, 06:02:41 pmYup, I'm afraid you're probably right here. I'd just email Nichicon and see if they'd reply. DK wasn't very helpful in this case, but they're probably not the right ones to ask anyway. I'd refrain from opening one up for now, as apart from seeing a loose roll inside, I wouldn't know what to look for and if there would be anything to tell me if it shouldn't be.Thank you.
DC Motor Armature Rewinding video - Page 1
Forum section: electronics / general

author: MathWizard
author_rank: Super Contributor
timestamp: September 16, 2021, 10:39:21 pm
content: I wonder what the price of motor repair is where I live? If I had the equipment I could do this, but it's a lot of tedious work for sure.https://www.youtube.com/watch?v=uQq8yWfqIDM&ab_channel=MajedaElectric%26Workshop

author: xrunner
author_rank: Super Contributor
timestamp: September 16, 2021, 11:06:45 pm
content: Day-um. I got to watch the whole thing a little later but it's quite a hole in the wall operation.

author: langwadt
author_rank: Super Contributor
timestamp: September 16, 2021, 11:16:26 pm
content: Quote from: xrunner on September 16, 2021, 11:06:45 pmmuch "worse"https://youtu.be/SqpD4khzqbw
Transformer circular box - Page 1
Forum section: electronics / general

author: xzswq21
author_rank: Frequent Contributor
timestamp: September 03, 2021, 09:24:38 pm
content: HelloI want to produce 1000 transformers so I need circular or simple boxes for our transformers. the material of the box should be heat resistant bcoz I put the boxes in an Oven at 120'C,Actually I'm thinking of a 3D printer but the material is a problem! I really don't know what I should do. Dimensions are 1"x1"x1" and I would prefer a Cylinder with a 1" diameter and a 1" height.Thanks

author: TimFox
author_rank: Super Contributor
timestamp: September 03, 2021, 11:19:00 pm
content: Carbon fiber and FR4/G10 composites are available as 1 inch diameter thin-wall cylinders.

author: David Hess
author_rank: Super Contributor
timestamp: September 04, 2021, 01:05:06 am
content: Quote from: TimFox on September 03, 2021, 11:19:00 pmhttps://www.mcmaster.com/garolite-tubing/FR4 and G10 are likely overkill, but Garolite is available with many compositions. Garolite CE is cotton, Garolite XX is paper, and Garolite LE is linen.

author: xzswq21
author_rank: Frequent Contributor
timestamp: September 16, 2021, 07:41:56 am
content: Can I buy a 3D printer to print such shapes?

author: Zero999
author_rank: Super Contributor
timestamp: September 16, 2021, 10:44:58 am
content: It probably could be 3D printed, the problem is winding the transformer and potting it, so it doesn't arc over. It has to be wound in a careful manner, to ensure the voltage between neighbouring wires doesn't exceed 500V, or so and potted with resin in a vacuum to exclude air pockets. Everything must be kept clean and free from moisture, salt and greese.You could even just use the box as a mould and remove it, after the potting has cured, but you need to ensure that there's enough space between the windings and the mould, so they don't poke out, when it's removed.

author: David Hess
author_rank: Super Contributor
timestamp: September 16, 2021, 12:18:05 pm
content: I would be really cautious about 3D printing a form which is going to rely on potting for high voltage insulation because of air gaps inside the 3D printed form.

author: xzswq21
author_rank: Frequent Contributor
timestamp: September 16, 2021, 06:10:07 pm
content: Quote from: Zero999 on September 16, 2021, 10:44:58 amI have a coil winder and I use cylindrical and segmented bobbin to reduce the wire insulation stress as following: plus I have a Vacuum Oven and a good electrical insulating epoxy resin, now my problem is finding a box,
Some special chips - Page 1
Forum section: electronics / general

author: TerraHertz
author_rank: Super Contributor
timestamp: September 15, 2021, 11:50:20 am
content: Sorting out some recently acquired old ICs, these interesting ones turned up.Pretty ceramic and gold packages. I'd thought they must be something special, but no. The two smaller ones are garden variety CMOS 4013. Well I guess they WERE special when made back in the 1970s. The larger one I don't know. 20 legs says it's not an LM3900. The black specks are dust from ancient anti-statric foam, disintegrating from age. It gets all over everything in the collection.Then there's this EPROM. It was among a pile I was removing labels and cleaning. It's just an old 2716, but it really is 'special'.I only noticed its specialness as I was holding it while wiping the top with a tissue soaked in turps to remove the label gum.Something inside moved! On close inspection it has at least two pieces of debris loose inside, that appear to be a short clipped-off component wire lead, and a drop of solder or something. They are completely loose. If the chip is tilted end up, they sort of disappear under the lip of the ceramic top lid. Holding it level and tapping it gently they bounce around inside. The thin gold bonding wires are looking pretty battered, and maybe some are broken by now.It had a label on it, so presumably it was in use at some time. I bet that made for an infuriatingly intermittent system, whatever it was.Lastly, here's one of many sheets of old black foam with ICs. Spot the mistake someone had made. There's a lot of this kind of mixup in the collection. Someone didn't really know their part numberings lore...

author: PA0PBZ
author_rank: Super Contributor
timestamp: September 15, 2021, 03:03:04 pm
content: Yeah I learned that if it starts with MC it's probably not what you think, and it could be difficult to find out what it is.

author: mawyatt
author_rank: Super Contributor
timestamp: September 15, 2021, 11:21:53 pm
content: Those RCA chips bring back fond memories of the early days of CMOS, RCA even had SOS (Silicon On Sapphire) versions for rad-hard environments. Vaguely remember a SOS version of the 1802uP, and recall Huges had an SOS CMOS fab as well.Thanks for the memoriesBest,

author: Benta
author_rank: Super Contributor
timestamp: September 16, 2021, 05:28:18 pm
content: The Hi-Rel/Space chips in the first pictures are beautiful, thanks for sharing. Gold-capped or white ceramic... Great!And yes, mixing Motorola TTL parts with RCA COSMOS parts is NOT the best idea

author: Benta
author_rank: Super Contributor
timestamp: September 16, 2021, 05:30:24 pm
content: Quote from: mawyatt on September 15, 2021, 11:21:53 pmIIRC, Plessey wastheexpert on SOS rad-hard chips, both as standard product series as well as ASICs.
HA1930-I/SS datasheet - Page 1
Forum section: electronics / general

author: Helix70
author_rank: Unknown
timestamp: February 12, 2020, 09:51:12 pm
content: Does anyone have a datasheet or any information for a HA1930-I/SS? It is found in lithium battery protection circuits, from Microchip, but i can't find any information about it at all.Thanks,Josh

author: conelec
author_rank: Contributor
timestamp: January 04, 2021, 07:25:46 am
content: I just came across the same part in an AEG battery pack. It's probably a PIC16(L)F1933 with factory programmed custom code. I had another different battery pack with the PIC16LF1933. I will try and see if I can read the device ID on the HA1930.

author: amyk
author_rank: Super Contributor
timestamp: January 04, 2021, 09:35:20 am
content: Unlikely to be custom programmed, just an obscure PIC variant for the Chinese market:https://www.microchip.com/forums/m434316.aspx?print=truehttps://www.amobbs.com/forum.php?mod=viewthread&tid=831236

author: haydent
author_rank: Newbie
timestamp: September 16, 2021, 10:56:40 am
content: I have this chip in a ryobi 2.5aH 18v lion battery pack. it seems even after i have replaced a dead cell and charged and manually balanced all cells to not want to work again even though it shows full voltage. likely in fail safe mode.Luckily you can buy replacement bms for these ryobi packs off ebay for $15
UR or URS and ETD Ferrite cores - Page 1
Forum section: electronics / general

author: xzswq21
author_rank: Frequent Contributor
timestamp: September 16, 2021, 07:49:44 am
content: HelloActually I need small size UR or URS and ETD Ferrite cores as following, I have found several suitable cores from TDK but I couldn't find them in online stores:Do you know how I should find them?Thanks
Aluminum PCB safe temperature range without risk of delamination? - Page 1
Forum section: electronics / general

author: XOIIO
author_rank: Super Contributor
timestamp: September 15, 2021, 06:27:42 pm
content: Hi all, so this is a bit of an odd question, but I've been stuck with a new 750w silicone heater for my 3d printer hoping to upgrade the bed for a couple months now.Unfortunately, finding a place to cut a new bed out is difficult, nay, impossible, and the thing I really wanted to do was get a sheet of mic tooling plate, however, it's only available in a thicker size than my current bed, which means that it would weigh 4lb apparently, a good chunk higher than my current print bed, and I was hoping to reduce moving mass, not increase it, since my printer has always struggled with ringing.So, I'm considering just slapping the new heater on top of the old aluminum pcb one that's built into the print bed. This is to help with some adhesion issues with ABS, but also because I want to explore some higher strength filaments with higher temp requirements. Also speeding up heating times is going to be really really nice.Before I risk ruining a $90 heater by making a mistake, I wanted to check as I am a bit concerned, is there much risk of aluminum circuit boards delaminating or separating with extended use at high temps, say up to 150c? The stock bed is rated at a max of 100, but that's likely mainly because it's 24v and struggles to even reach that temp.I'm sure there are different grades and ratings of aluminum pcbs, but I'm having trouble finding what the basically lowest quality ones would be rated at for maximum temperature consistently.

author: thm_w
author_rank: Super Contributor
timestamp: September 15, 2021, 09:40:21 pm
content: Depends on the grade of FR4 they used. Low stuff would be Tg of 130C, mid 140-150C, high 170C+. Garolite (FR4) from mcmaster is specced as 130 C.Looks like this company has 100-180C for example:https://www.epectec.com/pcb/aluminum-circuit-boards.htmlI would be tempted just to use it. Whats the highest, PEEK bed temp says 120C. I can't imagine anything printing on 150C?Could also use glass instead of aluminum.https://www.eevblog.com/forum/3d-printing/
Non-inductively bundling and IEC 61000-4-5 - Page 1
Forum section: electronics / general

author: Gusbert
author_rank: Newbie
timestamp: September 15, 2021, 10:08:53 am
content: There are a few ways of making a non-inductive bundle of long wire (fold in half, coil up; coil up, twist into figure-of-eight, flatten without folding) as required by IEC 61000-4-5. My question is why? I have done several days testing using 20m of coiled wire which I was told was "non-inductively bundled" but which turned out was not, as it had been coiled, twisted into a figure-of-eight, and the two lobes folded onto each other to make a smaller single coil again. Does using an inductively bundled wire like this invalidate the tests? I should have realised something was wrong when the wired jumped at 4kV/880A pulses.
Big Clive reverse-engineering challenge - Page 1
Forum section: electronics / general

author: amyk
author_rank: Super Contributor
timestamp: September 15, 2021, 04:16:02 am
content: In a recent video he took apart a "Buddha machine" which plays various prerecorded audio tracks:He also dumped the SPI flash it has, whose content can be found linked in the video description as well as attached below for convenience. The challenge is to determine the format of the data so that it can be reprogrammed with arbitrary audio.Some commenters have discovered the first portion of the data is a directory table that's been encrypted with a XOR key consisting of at least the sequence 1F 3E 7C F8 F0 C1 A3 67, since applying that will cause a list of offsets and sizes to various "files" in the image to appear (first one being at 600h); not all of them are the audio tracks. The key sequence looks like an LFSR to me, which would be appropriate for such a small size and cost-constrained COB ASIC, but I'm not sure if it could be longer, or the exact form of the feedback.The codec is also unknown, but is unlikely to be MP3 or anything of similar or higher complexity. It's also not known whether the audio data has been encrypted with a simple cipher. My guess is that the ASIC is not a microcontroller, the first few files in the image are tables of codec data and there is no executable code in it, and the audio data itself is encoded in a simple format. I've tried searching for the "CB" byte that seems to occur as the first one of each track, but haven't had as much luck asI did the last time I tried a similar challenge. Maybe others here who know more about ultra-cost-constrained audio codecs and the like may be able to figure it out.
[YT - "tech ingredients"] "DID WE JUST MAKE THE WORLD'S BEST THERMAL PASTE!?" - Page 1
Forum section: electronics / general

author: eti
author_rank: Super Contributor
timestamp: September 11, 2021, 10:41:11 pm
content: The professor is at it again

author: GlennSprigg
author_rank: Super Contributor
timestamp: September 12, 2021, 12:53:10 pm
content: When I was 'repairing' peoples old laptops, the biggest intermittent problem by far, (2nd to the ubiquitous Viruses etc...), wasold dried out Heat-Sink paste!!! causing them to thermally shut down. Modern laptops can run so hot, as they are 'pushed' sofar these days. Oh... I tell a partial lie... And education of laptop 'users' to NOT leave their laptop on top of their Doona/quilt whenin bed!!! The damn intake air is usually underneath, and gets totally blocked!!!

author: rsjsouza
author_rank: Super Contributor
timestamp: September 12, 2021, 01:10:28 pm
content: Quote from: GlennSprigg on September 12, 2021, 12:53:10 pmThis was a constant battle between me and my wife. This lasted until one day when her laptop shut down and she lost some work... Now it has become better - not perfect, but better.
Annual consumer lemming season … RUN! - Page 1
Forum section: electronics / general

author: eti
author_rank: Super Contributor
timestamp: September 09, 2021, 04:41:13 am
content: Oh boy, the annual Apple lemming fest is about to strike… run!!!I have one friend who gets all excited at this time every year, and bores me out of my mind with ONE MONTH of endless messages about every conceive nuance of his thought processes regarding his new iPhone purchase. People are so dumb.I don’t care. And this video sums it uphttps://youtu.be/SbmgV7Oyp0w
Cheapo DisplayPort to HDMI converter issues - Page 1
Forum section: electronics / general

author: eti
author_rank: Super Contributor
timestamp: September 08, 2021, 06:24:31 am
content: Bought a no name, cheapo DisplayPort to HDMI adaptor - it worked after messing around with "xrandr" in Linux (Elementary OS), but then the next day I had issues with green lines and/or flashing green pixels/flashing red pixels.I took it apart - there's a 48 pin (UNMARKED) IC in there, a level shift I am sure, but the solder job on the wires inside the DP end are as seen (attached) - they look barely soldered - the strands do not even appear to be tinned! Is this likely the cause? many thanks.
IEEE Spectrum article - Page 1
Forum section: electronics / general

author: jonpaul
author_rank: Super Contributor
timestamp: August 31, 2021, 09:08:59 pm
content: Hello all: My IEEE Spectrum article about a 1963 cipher machine and a huge espionage case Rubicon just went onlinehttps://spectrum.ieee.org/the-scandalous-history-of-the-last-rotor-cipher-machineabout a years work. Last photo has some HP and TEK equipment.Your thoughts appreciated!Jon

author: rsjsouza
author_rank: Super Contributor
timestamp: August 31, 2021, 10:07:57 pm
content: Jon, I started reading the article and it is a delight so far; I am really enjoying it. Congratulations and merci beaucoup!

author: 2N3055
author_rank: Super Contributor
timestamp: August 31, 2021, 10:21:52 pm
content: WOW Jon,that is very interesting topic, some very interesting and fascinating information and an excellent work on your side.Kudos!Thank you so much for sharing this!!Best,Sinisa

author: mawyatt
author_rank: Super Contributor
timestamp: August 31, 2021, 11:48:23 pm
content: Jon,Fascinating article, well done sirCongratulations on your career, and wonderful assortment of lab gearBest,

author: sandalcandal
author_rank: Unknown
timestamp: September 01, 2021, 06:31:41 am
content: Excellent photography! ...and an interesting article tooThe diagrams are nicely done too.

author: jonpaul
author_rank: Super Contributor
timestamp: September 01, 2021, 08:24:17 am
content: Rebonjour a tout et tous: Many thanks for the notes,Photos by super pro Peter Adams, it took an entire day.I hand sketched the diagrams and te IEEE Spectrum art dep created the neat diagrams.For the lab shot at the end, I had all the TEK 246x opened up for CAL and repair years ago.Ran into deep issues on #5, a 2465B CTT/GPIB/WR with PSU and other problems.With the IEEE article and travel, other projects, these five scopes occupied one bench all these years! Covers, shields and cases are under the bench.In the background you can see the HP spec analyzer, also 4195A, and TEK TM500 CAL sets.This is one of 4 benches setup. One for power electronics, one for audio, one for mechanical work and a bench for measurements, eg inductance, LCR, HyPot, 30 kV insulation....The lab was shot at the end of a very long day.Peter shot 100s over about 2 hours for this ONE shot and I was very tired.Very glad you liked the article!Bon Soiree,Jon

author: EPAIII
author_rank: Super Contributor
timestamp: September 01, 2021, 09:47:25 am
content: A very interesting article. Thanks for posting.

author: PaulAm
author_rank: Frequent Contributor
timestamp: September 01, 2021, 02:38:02 pm
content: Great article, thanks for posting the link.Someday I hope to build a replica Enigma machine, but it's way down on the priority list for now

author: RoGeorge
author_rank: Super Contributor
timestamp: September 07, 2021, 11:52:02 am
content: Wow!Thank you.
Q? What is that in the picture? A. WTC Antenna. - Page 1
Forum section: electronics / general

author: TechMaNac
author_rank: Newbie
timestamp: September 10, 2021, 01:21:49 am
content: behind my friend what is that in the picture?I know what it is and will let you all know Saturday before i leave for work.This should be fun, sad but fun to see what you think.Thank you and kind regardsHowie

author: TerraHertz
author_rank: Super Contributor
timestamp: September 10, 2021, 04:59:48 pm
content: The base of a radio tower, on top of a large building. Like the WTC tower perhaps?And you're posting it now, due to the coming 20th anniversary of the Neocons' brilliant idea.

author: AlbertL
author_rank: Regular Contributor
timestamp: September 10, 2021, 05:09:52 pm
content: Yes, WTC:https://www.facebook.com/WNYC/photos/p.10150601192486080/10150601192486080/?type=3

author: TechMaNac
author_rank: Newbie
timestamp: September 11, 2021, 12:46:32 pm
content: That was the antenna on of the WTC building #1Today 20 years ago I lost a dear friend, His name is Donald DiFranco.Donald used to work for CH 7 ABC He was in charge of changing analog to digital on the 110th floor and the roof.CH 7 ABCMissing Donald today and everyday
Burnt out fan oven element - is the white deposited powder safe? - Page 1
Forum section: electronics / general

author: eti
author_rank: Super Contributor
timestamp: September 06, 2021, 12:53:35 am
content: Hi all.I was heating my oven earlier, and suddenly heard a loud buzzing, arcing sound as you would when using an arc welder, replete with a fantastic white hot firework display inside the oven cavity. No big deal.Our element had burnt out previously, about 5 years ago, and due to their cheap cost (£8 each), I had the foresight to buy two, so the replacement only took 20 mins.Question: there was a very thin white coating on the interior of the oven, and the wire racks, which is assume is the magnesium oxide insulation powder that has sprayed out as it fizzled and buzzed - I’ve given the door and racks a quick wipe down - is this stuff toxic? Google says no.

author: Cerebus
author_rank: Super Contributor
timestamp: September 06, 2021, 01:11:20 am
content: Magnesium oxide is used as a dietary magnesium supplement, so entirely safe.If at all, you probably want to be more concerned about anything else that got sputtered out of its prior containment at the same time, but on such a recent oven it's likely to be fully RoHS compliant. The usual basic precautions ought to be all you need: don't breathe the dust (it's not like a face mask isn't a standard household supply nowadays), many harmless things are still respiratory irritants and give the whole oven a good clean before using it again. I doubt there's anything to fuss over in there but a little caution is never a bad thing.

author: AntiProtonBoy
author_rank: Frequent Contributor
timestamp: September 06, 2021, 01:12:08 am
content: Most metal oxides are non-toxic, but could be alkaline. Wipe with vinegar water, then clean out with soapy water.

author: Ian.M
author_rank: Super Contributor
timestamp: September 06, 2021, 01:14:12 am
content: Magnesium oxide of itself isn't notably toxic, in fact in the form of magnesium hydroxide, its used medicinally as an antiacid and laxative, however the deposit in your oven is likely to be heavily contaminated with various heavy metals from the element and its jacket. If you are concerned about this, (and as there is a possibility the jacket was stainless steel, containing chromium, you probably should be) as magnesium oxide is alkaline, I suggest thoroughly wiping down all surfaces with a generous amount of white vinegar to dissolve as much as possible, then with water to rinse away the residue, then letting it dry with the door open and finally run it at max temperature for min. 20 minutes or run a self-cleaning cycle. Any remaining residue after that should be firmly adhered to the surface its on and unlikely to transfer to your food.

author: eti
author_rank: Super Contributor
timestamp: September 06, 2021, 01:45:26 am
content: Thank you all. Much appreciated.
Simulation of a Flux Capacitor - Page 1
Forum section: electronics / general

author: GeoffreyF
author_rank: Regular Contributor
timestamp: September 01, 2021, 02:47:38 pm
content: OK a Mandlebrot Capacitor with Flux. The youtube author includes C code and other simulations. Now we just need a DeLorean.Geoff

author: rstofer
author_rank: Super Contributor
timestamp: September 03, 2021, 04:48:44 pm
content: The code is worth a look. It is possible to run the simulations and generate the movie - on a Linux box.There are other animations on the author's github.https://github.com/nilsberglund-orleans/YouTube-simulations
Grid Bias Cell.  1st Button-Battery!!! - Page 1
Forum section: electronics / general

author: GlennSprigg
author_rank: Super Contributor
timestamp: September 02, 2021, 12:05:30 pm
content: Well I'll beHornswaggled!!(Look it up... hahaha)... Just when I thought I knew it all !!, (AS IF!), along came the bias-cell.I just watched a tube-radio restoration of a 1937 Howard Radio, and it contained something I've never heard of before!!Negative grid-bias used to, (and later was again!), done using a combination of resistors and capacitors. In 1936, inventor Samuel Rubendesigned the 1st miniature dry-cell to use for this purpose!! (and on old battery powered tube radios, replaced the so-called 'C' battery)...He did a lot of work with/for 'Mallory' at the time. Usually, (as per today's methods/standards), the main body/cup of the device was theAnode, and the carbonized central inner disk on the other side was the Cathode!. (Today, the main-body is also +ve!!). They came in twostyles, 1-v and 1.25-v, though the 1-v was by far the most common. They had spring-loaded mounting clips, as in the following pic...Here's an Ad at the time, for their availability, and a typical cct diag showing their common representation...Evidently, one old radio rejuvenator found a N.O.S. one that still measured .9-v after 50 years!! In use, they literally drew no current, asit was basically a Voltage presence to do the biasing. Evidently, due to the degradation of the 'Connectors' themselves, and not the actualbatteries, they fell into disuse beyond WW-II. Samuel Ruben continued research that led to the development of miniature mercury batteries.These were widely used by the U.S. Army during World War II in portable radios and mine detectors. After the war, Ruben continued to workwith Mallory to develop alkaline batteries. The Duracell brand of batteries was introduced in 1964. Today, Duracell is a div of The Gillette Co.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: September 02, 2021, 01:24:08 pm
content: Never heard of that battery. Pretty cool.
Powered roadway ... by wind - Page 1
Forum section: electronics / general

author: kevinateev
author_rank: Regular Contributor
timestamp: September 05, 2021, 01:14:10 am
content: A youtube vid. about vertical wind turbines on lamp stndards. That is an idea! How do you think it compares to solar roadways?https://youtu.be/gcSnwW5v3f8
We are in for some space weather this week !!! - Page 1
Forum section: electronics / general

author: Beamin
author_rank: Super Contributor
timestamp: August 29, 2021, 05:54:50 am
content: "MAJOR FLARE WARNING: Sunspot AR2860 is big, angry, and it's directly facing Earth. The active region just unleashed a significant M4.7-class solar flare (Aug. 28 @ 0611 UT), probably hurling a CME toward Earth: movie. If current trends continue, a major X-flare could be in the offing, so stay tuned."www.spaceweather.comA solar tsunami went off hitting a sun spot towards earth that released a CME. We already heard the EM over shoerwave.Why doesnt anyone take this stuff seriously? No electricity means no ventilators or emergency services for COVID patients. This is why I cant sleep at night.https://youtu.be/9GTACdnY7ZQ

author: Beamin
author_rank: Super Contributor
timestamp: August 29, 2021, 07:54:46 pm
content: Does anyone know of a web site where you can see this coming? I used to know of one spaceweather doesnt show you the map so its not that site, cant find it through google. Storm hits tonight or tomorrow.

author: FireBird
author_rank: Regular Contributor
timestamp: August 30, 2021, 10:36:14 am
content: No need to get nervous.QuoteC- and M-class xray flares are rather weak and a G1-class storm is weak. It gets interesting if the flare is an X-class one and the predicted geomagnetic storm is G3 and above.

author: Bassman59
author_rank: Super Contributor
timestamp: August 30, 2021, 07:20:44 pm
content: I'm not sure the folks in New Orleans care about solar flares.

author: Zero999
author_rank: Super Contributor
timestamp: September 01, 2021, 06:22:28 pm
content: We're coming out of solar minimum, so an increase in flares is to be expected. No news here.
Taking the Silicon Lottery to a whole new level! - Page 1
Forum section: electronics / general

author: mrflibble
author_rank: Super Contributor
timestamp: September 01, 2021, 06:20:18 am
content: Insert COIN to continue. Press button now to win your AMD or Intel CPU!(Image credit: Nullpo_x3100 via Twitter)As found in this Tom's hardware article:https://www.tomshardware.com/news/this-amd-and-intel-vending-machine-is-literally-a-cpu-gamble"You have to insert a 1,000 yen bill (roughly $10) to get a ticket. There's a 1-in-30 chance that the ticket will unlock a Zen 2 CPU."That's certainly a novel way to unlock those clock multipliers...
Trying to source a GPIB connector - Page 1
Forum section: electronics / general

author: veedub565
author_rank: Frequent Contributor
timestamp: August 29, 2021, 01:08:44 pm
content: Anybody know where I might be able to source one of these in the UK ?Cinch/Amphenol 57-20240-23Without having to pay £200 postage like herehttps://www.ebay.co.uk/itm/233665573717?chn=ps&mkevt=1&mkcid=28It needs to be that part number as it has longer pins.

author: pqass
author_rank: Super Contributor
timestamp: August 29, 2021, 02:02:54 pm
content: Not Amphenol but should be compatible:https://www.digikey.co.uk/en/products/detail/norcomp-inc/111-024-213L001/955151Or:https://www.mouser.co.uk/ProductDetail/NorComp/111-024-213L001?qs=IGgAdOvCTsRyhSn%252BeI9L1A%3D%3DAlthough it does have the extra wire latch hardware.But shipping should be more reasonable.

author: veedub565
author_rank: Frequent Contributor
timestamp: August 29, 2021, 08:13:22 pm
content: I saw that, but I need the screw in type fitting not the wire clip. The fitting for the clip means the rear panel of the instrument wouldnt fit.

author: sokoloff
author_rank: Super Contributor
timestamp: August 29, 2021, 08:17:14 pm
content: That’s $10 to ship to the US.Have any US friends who could re-ship it for you?I can’t imagine it’d be more than $50 to re-ship.Add in a couple tenners for currency conversion and hassle and you’re way cheaper than 200£.

author: veedub565
author_rank: Frequent Contributor
timestamp: August 31, 2021, 09:47:00 am
content: Unfortunately not no, and tbh $50 shipping for a $6 part is still more than I'd want to pay.

author: dl6lr
author_rank: Frequent Contributor
timestamp: August 31, 2021, 12:59:23 pm
content: You can order the Norcomp and -using a drill press- drill out the rivet that holds the clip.

author: veedub565
author_rank: Frequent Contributor
timestamp: August 31, 2021, 07:41:57 pm
content: Yes that could work, thanks will give it a try

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: August 31, 2021, 07:46:26 pm
content: Just email the seller and ask about the shipping price. eBay has become such a mess for selling and its shipping calculator seems to derive its cost through a RNG. The seller has no control over what eBay calculates. I found when selling sometimes I have to enter a larger size for the box for it to select the right lower rate.
How to Test Saft 14250s (LiSoCl2) Batteries? - Page 1
Forum section: electronics / general

author: TPerk100
author_rank: Newbie
timestamp: August 29, 2021, 09:24:26 pm
content: I use about 25 SAFT LSG 14250s in my security system. Would like to be able to test these batteries somehow. Would prefer a piece of test equipment but can build tester if necessary…and I have plans etc.Any ideas?Thanks

author: tszaboo
author_rank: Super Contributor
timestamp: August 29, 2021, 09:46:06 pm
content: Test it how, for what? Remaining capacity? State of health? Remaining shelf life?

author: TPerk100
author_rank: Newbie
timestamp: August 29, 2021, 09:55:14 pm
content: Thanks for your reply,Remaining CapacityState of Health

author: babysitter
author_rank: Frequent Contributor
timestamp: August 30, 2021, 12:05:36 pm
content: subscribe, as voltage nearly just tells you its over.

author: tszaboo
author_rank: Super Contributor
timestamp: August 30, 2021, 12:20:12 pm
content: Quote from: TPerk100 on August 29, 2021, 09:55:14 pmRemaining Capacity: Load it with 8.5mA (for practical reasons this is usually just resistor) and measure voltage a few seconds later.State of Health: This can be accomplished a few ways. I typically just measure the short circuit current of the cell, given the ~5 Ohm ESR of the cell, this could be in the order of 500mA-1A . Open circuit voltage also helps determining it. Then calculate the ESR and that will give you a good indication on this.

author: TPerk100
author_rank: Newbie
timestamp: August 30, 2021, 01:05:25 pm
content: "subscribe, as voltage nearly just tells you its over"Subscribe to what? No load voltage is an accurate indicator???"Remaining Capacity: Load it with 8.5mA (for practical reasons this is usually just resistor) and measure voltage a few seconds later.State of Health: This can be accomplished a few ways. I typically just measure the short circuit current of the cell, given the ~5 Ohm ESR of the cell, this could be in the order of 500mA-1A . Open circuit voltage also helps determining it. Then calculate the ESR and that will give you a good indication on this"Thanks, to perform either of these I would like to have some sort of jig to insert the battery in (like a battery tester bracket) that would allow me to connect multiple leads to each end of battery. Any ideas?

author: tszaboo
author_rank: Super Contributor
timestamp: August 30, 2021, 03:03:59 pm
content: Any 1/2AA battery holder.

author: TPerk100
author_rank: Newbie
timestamp: August 30, 2021, 04:44:14 pm
content: Tanks again,Got'em on order.
Reverse Polarity - Page 1
Forum section: electronics / general

author: mrpenguin
author_rank: Newbie
timestamp: August 30, 2021, 04:20:21 am
content: Has anybody ever encountered a battery charger with its output polarity reversed?Was given a 42V LIPO battery charger which went 'POP' when plugged into the battery before it was connected to the mains.Owner had changed the supplied anderson plug to a different type with a lead attached has connected Red to Red and Black to Black (logically).Battery would not charge.I measured 10V DC output not 42V so definitely faulty.However when I took apart the newly fitted plug and measured again with black probe to black and red to red I got a negative reading.Reversing the probed to black on red and red on black gave a positive reading.I took the charger apart and the red wire was connected to the PCB with the silk screen label showing + and the black was labelled -, so connected correctly apparently.Either the PCB is mislabelled or the output polarity has been reversed somehow.The supplier insists the charger was tested before it was supplied.In all my 40 years of repairs I have never encountered anything like this..Even if the battery was connected in reverse as has happened to many of the chargers I have repaired I have never seen this.Any thoughts?

author: Vovk_Z
author_rank: Super Contributor
timestamp: August 30, 2021, 01:58:20 pm
content: Not all battery chargers have reverse polarity protection.
What do we mean by BW = 10Kbps; - Page 1
Forum section: electronics / general

author: Dinos Tsakalakis
author_rank: Newbie
timestamp: August 30, 2021, 03:17:01 pm
content: Hallo , i am studying Computer networks and i have a difficulty of understanding the term : BW=Kbps, I have done other subjects in the past that uses the BW referring to frequency spectrum but now i have something else, i suppose that this has to do something with the maximum transfer speed via a network cable ,made by a clock.Thenks,

author: ataradov
author_rank: Super Contributor
timestamp: August 30, 2021, 03:59:20 pm
content: This is just a general bandwidth in terms of final communication speed. It does not say anything about the clock or the bandwidth of the physical channel. Depending on the modulation type those things may vary a lot.

author: Marco
author_rank: Super Contributor
timestamp: August 30, 2021, 05:20:24 pm
content: https://en.wikipedia.org/wiki/Bandwidth_(computing)It's a contextual definition of bandwidth, usually they mean the peak throughput ... sometimes including overhead, sometimes not including overhead, there's no hard rule.

author: bson
author_rank: Unknown
timestamp: August 30, 2021, 07:39:45 pm
content: It's the Shannon limit for a given bandwidth, signal power, etc. They just skip the "Shannon limit" part.

author: Marco
author_rank: Super Contributor
timestamp: August 30, 2021, 09:58:57 pm
content: Nah, it's highly unlikely they mean channel capacity for a given signal strength when talking about computer networks.
So the Las Vegas Loop is not a joke? - Page 1
Forum section: electronics / general

author: MathWizard
author_rank: Super Contributor
timestamp: August 29, 2021, 09:46:47 pm
content: I never knew of the Hyperloop or how shady the whole thing seems, and/or Musk himself.But after this weekend seeing the non-hyper-loop for the Las Vegas convention center, I've been laughing at it, and worrying about it. Then there's all the money.

author: ataradov
author_rank: Super Contributor
timestamp: August 29, 2021, 10:08:27 pm
content: Too bad that if the car catches fire (it is good that electric cars never do that), then you are a toast.All the stupid praise is annoying. Traditional tunnel construction companies can build this thing just as cheap and fast if they are allowed to disregard 50 years worth of safety requirements.And here is another optimization - skip all the OSHA stuff and also hire children. Way cheaper that way.But here is good news - it will fall into disrepair and will be abandoned in a few years.

author: AlbertL
author_rank: Regular Contributor
timestamp: August 29, 2021, 10:23:11 pm
content: So essentially they've built a tremendously expensive tunnel to run a fleet of taxicabs!
Stanford University led team claims battery w. up to 6x energy density - Page 1
Forum section: electronics / general

author: daqq
author_rank: Super Contributor
timestamp: August 29, 2021, 06:22:12 pm
content: Title says it all:https://techxplore.com/news/2021-08-rechargeable-batteries.htmlThe actual paper (https://www.nature.com/articles/s41586-021-03757-z) is behind a paywall, didn't find it on the usual other sources, and it's not like I'd understand the chemistry. Opinions?

author: IanB
author_rank: Super Contributor
timestamp: August 29, 2021, 06:34:43 pm
content: Don't get excited just yet.The technology already exists to make rechargeable lithium metal batteries (these were the first kind to be produced). But lithium metal is rather reactive, and the batteries had a tendency to catch fire or explode. So lithium metal batteries were replaced by lithium ion batteries, which are the kind we have today. Lithium ion batteries contain no metallic lithium, so are much safer.In this experiment, they propose to have not only lithium metal, but also possibly sodium metal! Sodium metal is vastly more reactive than lithium metal, so the thought of putting that in a battery is scary.In short, an interesting experiment perhaps, but a very long way from being a safe, reliable and practical design.Another point is that if you store 6x the energy inside a battery, it will take 6x longer to charge, and also if it fails it will release 6x the energy in unwanted heat, fire and flames. The big problem with electric batteries is you only have to accidentally short circuit them to let the energy out. The more energy they are storing, the worse the outcome.

author: daqq
author_rank: Super Contributor
timestamp: August 29, 2021, 06:37:21 pm
content: QuoteI think the more interesting thing here is to store 1x the energy in 1/6th of the volume/mass.But I understand your remaining points.

author: rstofer
author_rank: Super Contributor
timestamp: August 29, 2021, 09:01:16 pm
content: The holy grail in battery design is related to EVs. Increasing range is going to require hauling around more kWh. If the battery is a lot smaller, less energy is wasted hauling it. OR, for the same amount of weight, I get a lot more range. I hope...I agree, if there is a hazardous material in addition to whatever we have today, the new thing is a non-starter. But maybe for stationary batteries, it's no big deal.Here's a mega scale 'oopsie' at Australia's "Victorian Big Battery" site.https://www.cnbc.com/2021/07/30/tesla-megapack-caught-fire-at-victorian-big-battery-site-in-australia.htmlStill, these big battery sites are going to become more prevalent as more load is carried by solar.
Fascinating historical item - the Poll-O-Meter - Page 1
Forum section: electronics / general

author: AlbertL
author_rank: Regular Contributor
timestamp: August 29, 2021, 08:44:23 pm
content: A TV audience-measurement system from the 1950s which apparently didn't catch on:That van with the giant rooftop antenna slowly prowling neighborhood streets has a wonderful vintage sci-fi creepiness!
SurgeX (Ametek) UPS-2000-OL Online Double-Conversion UPS (2000VA/1800W) - Page 1
Forum section: electronics / general

author: Demon Core
author_rank: Newbie
timestamp: August 29, 2021, 05:27:41 pm
content: Hello forum, I found a brand new in box SurgeX (Ametek) UPS-2000-OL with a retail of over $2,000.00. The price was too good to pass up so I snagged it. I have an NVR 16 channel security system, router, alarm, etc. I could hook it up to or power my TV, AVR for a brief period of time. Does anyone have direct experience with SurgeX (Ametek) online double-conversion UPS'? I'm also worried it will be too noisy since the fans run continuously as an online unit. I believe it's rated for <50db at 1M, but I have no idea how that translates in the real world until I receive it. SurgeX is very well known in the audio/video/home theater world for their Advanced series mode protection devices as opposed to typical MOV surge protectors. Here are the specs:SurgeX online double conversion standalone UPS battery backup solutions deliver clean continuous power, via online double conversion technology, to ensure the safe shutdown of equipment in the event of an outage. All incoming power is converted from AC to DC and then back to AC. If the main power is interrupted, the batteries are still holding up the incoming DC supply to the inverter, so the load continues to be supplied with absolutely no interruption whatsoever. The zero transfer time guarantees mission critical equipment remains up and running.~Online double conversion technology~True sinewave output~Controllable receptacles~Hot swappable battery~Configurable as tower or 19” rack~Intuitive LCD screen~Optional SNMP card to monitor and manage the UPS via the networkThe UPS-2000-OL shall be a two-rack-space or tower on-line UPS unit in a steel and plastic enclosure. It shall operate at 120 volts AC at both 50 or 60Hz and have a 6-foot, grounded, 3-wire #12 line cord. There shall be 5 grounded AC receptacles on the back panel. This unit can accommodate additional battery cabinets to extend its autonomous run time. Overall dimensions shall be 3.39” H x 17.24” W (or 19.0” W with ears) x 20.20” D. Weight shall be 58 pounds. The UPS-2000-OL shall have a total load rating of 2,000VA / 1,800 Watts. This unit can accommodate an optional SNMP network card for unit monitoring and shutdown.
Need help with translation of a section of a Chinese datasheet (WCH CH455G) - Page 1
Forum section: electronics / general

author: HwAoRrDk
author_rank: Super Contributor
timestamp: August 28, 2021, 06:54:13 am
content: I am planning to write some code that works with the WCH CH455G LED display driver and key matrix controller chip, so I am presently reading the datasheet.I found an English language datasheet (may or may not be official - I don't know), and while the translation is not great, it's reasonably understandable. However, theChinese language datasheetis a newer revision (1E versus 1C), and there are a couple of things I notice are different.One of them is that apparently certain revisions of the chip have a 'KOFF' configuration parameter, which disables key matrix scanning. But running the Chinese datasheet through Google Translate gives me information about this flag that is a bit ambiguous, where I suspect some meaning has been lost. I would appreciate it if anyone can provide a more accurate translation.The Chinese says:QuoteWhat I got out of Google Translate is:QuoteAre they actually saying thatonlychips with batch number 20941XXXX support KOFF? Or are they saying that all chips with batch number 20941XXXXor latersupport it? One might sensibly assume the latter, but you never know...Attached is a screenshot of the Chinese datasheet in case the plain text doesn't make it through the forum unmolested.
Please help identifying these two marks on a step up transformer - Page 1
Forum section: electronics / general

author: Goophy629
author_rank: Contributor
timestamp: August 24, 2021, 04:21:29 am
content: They are on a 110/120v to 220/240v step up transformer (those travel size thing),not sure what they really mean.

author: bob91343
author_rank: Super Contributor
timestamp: August 24, 2021, 04:39:44 am
content: I suspect the second one indicates for indoor use only.

author: Cubdriver
author_rank: Unknown
timestamp: August 24, 2021, 04:54:58 am
content: The first one appears to indicate that it is an isolation transformer (no electrical connection between primary and secondary)https://www.iso.org/obp/ui#iec:grs:60417:5222-Pat

author: old-jo
author_rank: Contributor
timestamp: August 24, 2021, 06:59:51 am
content: For the first symbol:http://www.cycloflow.com/2014/11/markings-and-symbols-on-transformers.htmlQuoteThe ISO/IEC symbol that does not have inside-pointing arrow:https://www.iso.org/obp/ui#iec:grs:60417:5957

author: Goophy629
author_rank: Contributor
timestamp: August 31, 2021, 09:39:35 pm
content: thanks all for the info