hybridfree/eevblog-posts huggingface dataset:
Testing a motor run/start cap. How do -you- do it? - Page 1
Forum section: electronics / general

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: January 11, 2022, 04:13:34 am
content: Just interested how everyone does it.Seen some nasty y/t vids. One thing I don't like is the clumsy shorting out with the screwdriver.I know it depends on what meters you have on hand and how extensively you want to test. Most of us in the field will know when the cap is dead and replace it. Then the motor works again. Chuck the old one in the garbage.

author: floobydust
author_rank: Super Contributor
timestamp: January 11, 2022, 04:42:22 am
content: I test them like any other capacitor (LCR meter) BUT because they have mechanical failures and the pressure switch inside, they need to get banged around as well. They can go intermittent.

author: james_s
author_rank: Super Contributor
timestamp: January 11, 2022, 04:44:34 am
content: I usually use the capacitance function on my multimeter as a basic test, but the easiest thing to do is usually swap in a known good capacitor of similar value and see if the motor runs.

author: floobydust
author_rank: Super Contributor
timestamp: January 11, 2022, 05:04:19 am
content: Multimeter capacitance test is crap due to timing single-slope. Leakage current misleadingly gives a higher C reading because it's taking longer to charge up. Cheap electrolytics have a weird electrolyte that has high leakage current and gives bizarre readings, almost like dealing with a 1/2 cell.So the capacitance reading from a multimeter is not much to go on.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: January 11, 2022, 05:13:41 am
content: I see a lot more of the CBB65 types 40-70uF so they can be unwieldy. As James says you know when they've had it..I thought it was just me that just test jigs the things.

author: IanB
author_rank: Super Contributor
timestamp: January 11, 2022, 05:27:18 am
content: I'm not too bothered about shorting with a screwdriver as the capacitor should already be discharged by the motor windings.In my case it was a simple run capacitor, and the diagnosis was firstly that the motor did not start well, and secondly the measurement of the capacitance was low.I don't know much about start capacitors, but I suspect the diagnosis is similar.
Hope someone can help to correct the English abstract of my master thesis - Page 1
Forum section: electronics / general

author: China NewBoy
author_rank: Regular Contributor
timestamp: January 11, 2022, 12:56:26 am
content: I am a Chinese master student，My supervisor said that the English abstract part of my master's thesis is very poor, I don't know how to correct it.Hope someone can help me===========================================================================Line loss rate is an important parameter for quantifying grid transmission efficiency, and overall quality of electrical distribution system, Primary causes usually include leakage, partial discharge, and illegal use of electricity, among others. Such losses cause both financial harm to electric utilities and danger to users. The current abnormal line loss detection methods are power line carrier detection and manual detection. because the watt-hour meters are installed at a fixed and dispersive location, the power line communication method is inconvenience. The clock in the watt-hour meters is inaccurate, it causes large errors in the calculation of line loss rate. Manual detection faces the problems of high labor cost and low efficiency.To solve the problem of line loss monitoring and troubleshooting in low-voltage stations, an abnormal loss detection system for power grids based on IoT is designed.In this thesis, we designs five kinds of line loss detection devices for three kinds of power supply areas : 1.urban building; 2.rural residential; 3.factory area.This system locates faults by modeling the power network as a tree topology, and measuring at each node the total input power, branch line output power, and user power. Considering the system's wide distribution and system cost, the NB-IoT module is used for uploading data from each location. To ensure efficient transmission, the MQTT/HTTP protocol is used to communicate over the internet. An internet time service facilitates real-time synchronous monitoring, reducing calculation errors. By calculating the line loss rate of each node, the system can identify when and where the line loss exceeds usual or expected amount.This experiment proves that the system can make the current power industry line loss monitoring smarter, reducing workload.

author: jpanhalt
author_rank: Super Contributor
timestamp: January 11, 2022, 01:02:33 am
content: Sounds like the same thread you started here:https://www.eevblog.com/forum/chat/there-is-a-problem-with-the-translation-of-my-masters-english-abstract/msg3852689/#msg3852689Why not continue on where that left off?

author: China NewBoy
author_rank: Regular Contributor
timestamp: January 11, 2022, 01:10:17 am
content: Quote from: jpanhalt on January 11, 2022, 01:02:33 amThank you, I want to delete this post, but I can't seem to delete it
(w2aew scope video) - need the PDF please  - Page 1
Forum section: electronics / general

author: eti
author_rank: Super Contributor
timestamp: January 10, 2022, 09:09:48 am
content: Alan Wolkes’s superb scope tutorial herehttps://youtu.be/niBGkqlh2XYHas a PDF linked under it, but it’s locked to private, kinda defeating the object of sharing the link. Does anyone have a copy? Thanks if you do.

author: newbrain
author_rank: Super Contributor
timestamp: January 10, 2022, 12:30:58 pm
content: You probably already know, but a longer video presumably from the same or similar session (and many others from him, plus further information) is linked in this thread:https://www.eevblog.com/forum/beginners/oscilloscope-training-class-(long)/As W2AEW is a member here, and his page states he was active recently on the forum (last post 5th of January), maybe you can try to PM him!
Where to manufacture hypersil transformer (with SM102b core) - Page 1
Forum section: electronics / general

author: dzseki
author_rank: Frequent Contributor
timestamp: April 08, 2020, 06:49:08 am
content: At work we have an instrument which uses a hypersil mains transformer on SM102b core. This transformer is custom specified, our vendor ceased the production of the core material and therefore does not accept new orders.I thought it would be easy to find new manufacturer, but it seems not!Do you you know any company who sells custom hypersil transformer, or at least produce the core material (SM102b) and the related hardwares?It would be good if the manufacturer would be in Europe, but meh if we don't have any alternative, then we are open for anything...We have contacted a Czech company Therma FM, but they did not care to respond. Also we have some older core set from VAC (Vacuumschmelze GmbH) Hanau. I've just contacted them waiting for reply but their web page doesn't show any reference to wound C core materials anymore, so I am not very optimistic.

author: nctnico
author_rank: Super Contributor
timestamp: April 08, 2020, 09:32:08 pm
content: Many years ago I had a transformer wound by these guys:https://www.custom-transformers.co.uk/Prices are reasonable and (at least back then) they where responsive to enquiries.

author: andy3055
author_rank: Super Contributor
timestamp: April 10, 2020, 05:59:58 am
content: Here is another possible source:http://www.epd-inc.com/2011/08/hypersil-cores/

author: dzseki
author_rank: Frequent Contributor
timestamp: April 10, 2020, 07:23:59 am
content: Quote from: andy3055 on April 10, 2020, 05:59:58 amI have found this as well, while I haven't contacted them, the fact that the last update on the page from 2016 is suspicious...

author: daniel10351035
author_rank: Newbie
timestamp: January 13, 2022, 04:00:50 am
content: We have a Chinese supplier we used to work with. Give this one a try.https://www.elecmattech.com/products1.aspx?id=1008&sort=0
Inverter Generator module "balance" trim pot function - Page 1
Forum section: electronics / general

author: Dehv
author_rank: Contributor
timestamp: January 09, 2022, 04:44:35 am
content: Unit has mini pots labelled Voltage, Current, overload and balance.Wtf is balance? Maybe ramp from eco mode?

author: NiHaoMike
author_rank: Super Contributor
timestamp: January 09, 2022, 05:13:15 am
content: My guess is DC balance.

author: Dehv
author_rank: Contributor
timestamp: January 09, 2022, 07:18:29 pm
content: Found this from Jon Watte on quora:"The inverter has a measured efficiency curve. E g, at output power X (or output current X, which together with the average voltage, gives you power) it is measured to be Y efficient.Thus, you can easily calculate the (average) power balance — DC voltage in x DC current in equals average AC voltage out x AC current out divided by efficiency in percent. (The rest of the power goes into heat.)Typically, there is a “sweet spot” where it is most efficient, and typically this is close to the maximum rated continuous load, and efficiency falls off with lighter loads.A cheap inverter for occasional use may be only 80% efficient at average load. A high-quality inverter for whole-house use might be 96% efficient, which sounds like only 16% better, but the cheap one actually generates 5 times as much heat as the quality one in this case. (20% heat versus 4% heat.)"
Just came across this lady. History of electricity - Page 1
Forum section: electronics / general

author: SiliconWizard
author_rank: Super Contributor
timestamp: January 08, 2022, 10:22:54 pm
content: Also came across the video about Ohm yesterday!History is always interesting. Do we ever learn from history? I'm not sure.

author: armandine2
author_rank: Frequent Contributor
timestamp: January 08, 2022, 10:43:03 pm
content: G7PSK - you and Homer! [ed. and EEVblog] must be something in the air.

author: armandine2
author_rank: Frequent Contributor
timestamp: January 08, 2022, 10:49:09 pm
content: Quote from: SiliconWizard on January 08, 2022, 10:22:54 pmalways repeating?
Any idea who OEMs this DMM?  Milwaukee 2217-20 - Page 1
Forum section: electronics / general

author: bdunham7
author_rank: Super Contributor
timestamp: January 07, 2022, 05:13:52 am
content: https://www.grainger.com/product/MILWAUKEE-MILWAUKEE-R-2217-20-Series-5MLK1

author: thm_w
author_rank: Super Contributor
timestamp: January 07, 2022, 10:23:37 pm
content: Grainger says USA but thats wrong, other sites list Taiwan. Manual says printed in Taiwan.Milwaukee is part of TTI group. Packaging is cheap clamshell and leads look fairly cheapish.They also have a black on white display model, and a clamp meter:https://www.milwaukeetool.com/Products/Instruments/Digital-Multimetershttps://www.milwaukeetool.com/Products/Instruments/Clamp-MetersThe style is a bit similar to Kaiweets:https://kaiweets.com/collections/allbut thats not Taiwan

author: floobydust
author_rank: Super Contributor
timestamp: January 08, 2022, 03:59:26 am
content: I would guess Milwaukee gave their specs and feature list, as well as the need for a distinctive enclosure, to a contract OEM.Because they are liable, the product will have proper fuses and 61010 approvals. Like Greenlee. What I can find...Uni-Trend can be found under trade names:Amprobe,Milwaukee, Grainger, Minipa (Brazil), Voltcraft, Greenlee (USA), Digimaster, Urrea Surtek (Mexico),SPERRY InstrumentsUSA, Tenma,PeakTech, Koban,CDI Electronics(USA), MCM,Di-LOG(UK),Klein Tools(USA),EXTECH Instruments,Southwire,UNI-TMGL Global Solutions Limited - Kowloon Hong Kong SAR, china can be found under trade names:Commercial, Commercial Electric, DAWSON, Mastercraft, MASTECH, MAXIMUM, Multimetrix, STANLEY FATMAX, LAP, MACTOOLS, AMES, Power Probe.CEM (Shenzhen Everbest Machinery Industry Co. Ltd) can be found under trade names:CEM, Amazon {multimeters}, Craftsman, Kobalt, Utilitech.
Drawing game from comedy sketch about requirements meeting - Page 1
Forum section: electronics / general

author: Kasper
author_rank: Frequent Contributor
timestamp: January 07, 2022, 07:24:01 pm
content: This is one of my favorite comedy videos and as I work my way through the different seats at the table I find it even funnier. I've made an attempt at following these requirements and I'll share it later but first, I'd like to see what the other members here come up with.Here are your requirements, please see the video if you'd like further explanation:Draw 7 red lines2 with red ink2 with green inkThe rest with transparent inkAll perpendicularIn the shape of a kitten
Keysight 34465A saving temperature settings - Page 1
Forum section: electronics / general

author: Robaroni
author_rank: Frequent Contributor
timestamp: January 06, 2022, 01:14:32 pm
content: Hi,Is there a way to save my temp settings on the 34465A so I don't have to redo them every time I use my probe?Thanks for the time and help,Rob

author: Dr. Frank
author_rank: Super Contributor
timestamp: January 06, 2022, 04:34:34 pm
content: Hi Rob,that's easy.Configure your 34465A to TEMP, and the sensor settings you need.Then go to Utility - Store/Recall, select a name for your setting, and STORE STATEWhenever you recall this state, it will exactly come up in this configuration.You can also make this setting your default boot setup by storing the configuration and setting the DMM to "Power on - User defined". See manual for details, where /how to store this correctly.Frank

author: Robaroni
author_rank: Frequent Contributor
timestamp: January 06, 2022, 07:11:10 pm
content: Thanks Frank, appreciated.

author: jonpaul
author_rank: Super Contributor
timestamp: January 06, 2022, 08:51:58 pm
content: Bonjour, A fantastic meter!In Utility you can configure the startup to default to factory, user OR to restore previous(SHIFT) Utility>>store/recall>>power ONSelections ...LASTUSER DEFINEDFactory DefaultSuggest LASTSame applies to entire series 34461A, 34470A etc.Bon courage!Jon
Printed Circuit Board Porn? What Were The Nokia Engineers Thinking? - Page 1
Forum section: electronics / general

author: madsbarnkob
author_rank: Frequent Contributor
timestamp: January 05, 2022, 10:19:21 am
content: Two "HEPPU" (ordinary guy) ICs after the ADC frontend, feeds data to the "PIMU" (single women below 30 year old) IC. Loosely translated with help from FinsNokia engineers likes to nickname their ICs with Finnish names or slang. These ICs comes from the teardown of a cellular base station amplifier for 3G mobile phone networks, the Nokia Siemens Networks 3G Flexi FRGL 2x50W 1800 MHz:https://kaizerpowerelectronics.dk/teardown/nokia-siemens-3g-flexi-2100mhz-50w-frgl-amplifier-teardown/[ Specified attachment is not available ]

author: Nominal Animal
author_rank: Super Contributor
timestamp: January 06, 2022, 06:55:06 pm
content: Considering the language and culture nuances, translating to English as used in American comedies in 1990-2010, "heppu" ≡ "dude" and "pimu" ≡ "chick", with almost perfect mapping of subtext and connotations.

author: SiliconWizard
author_rank: Super Contributor
timestamp: January 06, 2022, 07:02:34 pm
content: Ok cool. =)It's actually a pretty common thing to give ASICs nicknames.So yeah, the Amiga had Paula, Fat Agnus, ... what where they thinking at Commodore?Or is it because the nicknames are "chick" and "dude" instead of first names or very funky names (you realize what a "fat agnus" would be?)Not sure that is worth even talking about, but hey. Who am I to judge.
SMD Identification - Page 1
Forum section: electronics / general

author: MIATA
author_rank: Newbie
timestamp: January 05, 2022, 04:21:28 am
content: Can anyone help identify this I.C. (U11) in my Fisher F22 Metal Detector. The Marking Code on it is BWWY. It's an SOT-23-6 package. I've tried all of my SMD Marking Code sites and can't find it on any of them. I think it is probably a voltage regulator, but not positive. I know that Pin 6 is Vcc and Pin 2 is Gnd. (Vcc is 3V). Not sure about the other pins without further reverse engineering. Any help would be appreciated. Thanks.

author: amyk
author_rank: Super Contributor
timestamp: January 08, 2022, 01:31:32 am
content: MCP1640BALT1128TR

author: MIATA
author_rank: Newbie
timestamp: January 08, 2022, 08:43:18 pm
content: Thanks for the info!!! It definitely looks like a likely good number. Looking at the Datasheet for MCP1640B, I don't see where they spell out the Marking Code of BWWY, but the pinout looks good. Looks like it might be hard to find this part available in an SOT23-6 package. How did you find this number as a cross? Thanks again for your help!!

author: amyk
author_rank: Super Contributor
timestamp: January 08, 2022, 11:43:22 pm
content: https://ww1.microchip.com/downloads/en/DeviceDoc/20002234D.pdfpage 21,Don't rule out ALT1128TR (but at first glance it may be a clone)

author: MIATA
author_rank: Newbie
timestamp: January 09, 2022, 03:20:31 am
content: Yep, I saw the marking codes on page 21. The ALT1128TR looks like it may be even harder to find than the MCP1640B. Looks like out of stock and long lead times on both. I'll keep looking. Let me know if you would happen to see any source for either of these. Thanks again for finding these!

author: amyk
author_rank: Super Contributor
timestamp: January 10, 2022, 01:50:34 am
content: Were you not aware of the chip shortage that's currently happening?There might be other compatible drop-in replacements, you can search for sot23-6 boost converters with the same pinout, and compare datasheets.

author: MIATA
author_rank: Newbie
timestamp: January 10, 2022, 05:11:41 am
content: I found a supplier (Futurlec) that had stock of MCP1640T, which I think should work. I ordered a couple of them (only $.65 each). We'll see what happens. Thanks again for the help.
Recommendations for quality IT/Programming websites? - Page 1
Forum section: electronics / general

author: krokodyl1220
author_rank: Contributor
timestamp: January 04, 2022, 05:44:56 pm
content: Hi all,I am looking for quality websites for content related to programming, general IT. What is interesting for me is any source that has news, general articles about the industry (meaning - not necessarily tutorials), articles about working issues, tips on strategies for working in the industry and similar.What I have found so far and what seems like the good sources:- techdirt.com- wired.com/tag/programming- developer-tech.comDo you have any suggestions as to what websites to look for or what sites you visit?
"Octopus" curve tracer: component choice question - Page 1
Forum section: electronics / general

author: eti
author_rank: Super Contributor
timestamp: December 29, 2021, 08:48:31 pm
content: Is it important that the resistors in this circuit are 1/2 watt (except the 1 watt one)? I only have 1/4 watt - I know I can double up, but want to know if it is necessary? Thanks!

author: bob91343
author_rank: Super Contributor
timestamp: December 29, 2021, 09:10:45 pm
content: Even if all the 6.3V were across the 560 Ohm resistor, the dissipation would be about 80 milliwatts so don't worry about it. 1/8 Watt resistors would even be okay.

author: nali
author_rank: Frequent Contributor
timestamp: December 29, 2021, 09:42:27 pm
content: I think someone somewhere got their Ohm's Law calculations wrong for the 1K resistor too... it should be 1mW not 1W!

author: eti
author_rank: Super Contributor
timestamp: December 29, 2021, 09:43:46 pm
content: Quote from: nali on December 29, 2021, 09:42:27 pmHehe, thanks!

author: eti
author_rank: Super Contributor
timestamp: December 29, 2021, 09:44:33 pm
content: Quote from: bob91343 on December 29, 2021, 09:10:45 pmMuch obliged, thanks for taking the time to help. Happy 2022, when it arrives!

author: eti
author_rank: Super Contributor
timestamp: January 01, 2022, 09:17:14 pm
content: So does one connect the outputs of the tracer directly to the scope, or to the probes of the scope leads?

author: NiHaoMike
author_rank: Super Contributor
timestamp: January 01, 2022, 09:57:20 pm
content: I would say to use coax lines with BNC plugs attached, the signal level is pretty small. Also, instead of a transformer and voltage divider, how about a cheap microcontroller operating as a sine wave DDS with a RC filter to filter two opposing PWM outputs? Then it can be battery operated and variable frequency.

author: eti
author_rank: Super Contributor
timestamp: January 01, 2022, 11:05:32 pm
content: Quote from: NiHaoMike on January 01, 2022, 09:57:20 pmA good idea, I have a DDS module here, but the very purpose of this thing is to keep it simple for me, and keep my focus on fundamentals. Once we introduce micros into it, we wander off down the side lane which is the insanity of software, and all that nonsense - I am trying to learn about component characteristics, not how to write C code or learn a new SDKComputers and digital garbage is already too much in our faces all the hours of the day, and I am already on the PC too much, and so this HAS to be analogue only, if for nothing else, than for the most crucial thing - MY SANITYI like to K.I.S.S. - thanks for the suggestions.

author: eti
author_rank: Super Contributor
timestamp: January 04, 2022, 09:27:43 am
content: works
hameg 203-6 scop the horizntal went left - Page 1
Forum section: electronics / general

author: oferfolk
author_rank: Newbie
timestamp: September 24, 2021, 06:23:19 am
content: hi everyonei have the 203-6 for over 30 years and it worked fine and also look like new with no any rusti just did not use it for a few years and i tried it and the line went left showing 2 cm and only can move more left and not to center.it also the same with component and channels.nothing is burn there. all look nice and clean.i clean the switches and everything i could think of.what else can i check ?

author: Greybeard
author_rank: Frequent Contributor
timestamp: January 03, 2022, 10:29:07 pm
content: Find the user manual in the web.Check internal supply voltages and hum.Check for overheated resistors, rectifires (or other components).Check for leaking/blown electrolytic caps
Best way to collimate a fiber coupled laser - Page 1
Forum section: electronics / general

author: Neviolograpy
author_rank: Newbie
timestamp: January 02, 2022, 07:44:52 pm
content: I have a laser diode, an array of diode at 808 nm, for a total power of 100W CW coming out with a multimode optical fiber (105 um fiber core, 0.22 NA).I would like to use it for engraving, and I need to transform its output into a collimated beam of about 30 mm in diameter.I know these lasers are not made for the purpose, but for pumping Nd: YAG rods etc ...Anyhow I wonder which is the best optical system.The two solutions I found are the following, and I can't decide which of the two is the best, that is, it allows me to obtain an output beam with less divergence.1. use a pre-assembled collimator (Edmud Optics, Thorlabs...) that comes out with a diameter of 2-3 mm, and in series build an ad hoc beam expander, for example a 10x with first aspherical lens of f = -50 mm and second spherical lens with f = 500 mm (therefore large focal lengths)2. exploit the diverging beam exiting the optical fiber (0.22 NA = 25 ° full angle) and then use only one pcx condenser lens with NA 0.22-0.25 to collimate the beam (therefore f = 70-75 mm).What is better in terms of output beam divergence and what costs me less in terms of the cost of optics?
Neon lamp leads corroding - Page 1
Forum section: electronics / general

author: Xenon
author_rank: Contributor
timestamp: January 02, 2022, 11:36:43 am
content: In old CRT equipment (being a monitor or scope) you often find neon lamps in the HV area.For some reason yet unknown to me, the leads of these lamps are often heavily corroded.The corrosion is always where the lead enters the bulb. This corrosion makes the lead very brittle, and it snaps at the lightest vibration.Does anyone know why this happens? All other surrounding components are fine, only the neons suffer from this.

author: SeanB
author_rank: Super Contributor
timestamp: January 02, 2022, 11:59:17 am
content: Going to take a guess it is because the leads are made from steel wire, as glass will adhere to steel, or rather to iron oxide, quite well, so the leads are made from nice clean steel wire, and then are cleaned after manufacture with an acid dip, so that the following tin plating can be adhered to this nice clean surface. Likely there is always a residue of acid trapped in the interface area to the glass, and this gradually reacts with oxygen and water vapour in the air, to corrode the steel in the area just by the glass, eventually corroding the lead off. Neon lamps are made as cheap as possible, as they are made in the million in automated lines, so material cost is paramount, so steel wire instead of a non corroding metal, and then tin plate to enable them to be soldered or crimped with a reliable connection.You see the same in CFL lamps, where the filament leads are steel wire, but are not coated, as they typically get wire wrapped around a post, making a gas tight connection, but use the same wire and sealing method. Neon lamps however do not run hot, which would keep the seal dry, so they will corrode with time.
Are all “858D” desoldering brands the same? - Page 1
Forum section: electronics / general

author: eti
author_rank: Super Contributor
timestamp: December 29, 2021, 09:49:44 am
content: I’ve seen an “858D” on eBay for £19.99, but it’s not Attention brand. Am I to take it that they’re all from the same factory and rebadged?It’s this one, thank you;https://www.ebay.co.uk/itm/185180310223?hash=item2b1d9b4acf:g:f4EAAOSwF7hhnKjc

author: tom66
author_rank: Super Contributor
timestamp: December 29, 2021, 10:25:27 am
content: Looks subtly different to my 858D clone, so I'm going to cautiously say 'no'.The 858D as a model designator, I believe, is a clone of the Atten or Quick 858D, which is probably a clone of some other rework station. So there are probably a number of companies that produce universally designed products here. Such is the way of China.

author: eti
author_rank: Super Contributor
timestamp: December 29, 2021, 09:05:32 pm
content: Quote from: tom66 on December 29, 2021, 10:25:27 amThank you very much

author: thm_w
author_rank: Super Contributor
timestamp: December 29, 2021, 10:23:39 pm
content: No, not the same, but generally near enough that it doesn't matter.This should be in the "other equipment" forum section btw.https://www.eevblog.com/forum/reviews/help-identifying-component-on-858d-rework-clone-ksd858dp/https://www.eevblog.com/forum/reviews/experience-with-zhongdi-zd-8908-or-rs-pro-858d-hot-air-stations/https://www.eevblog.com/forum/repair/yihua-853d-soldering-station-details-about-fan-circuit-repair-incl-schematic/https://www.eevblog.com/forum/reviews/youyue-858d-some-reverse-engineering-custom-firmware/

author: amyk
author_rank: Super Contributor
timestamp: December 29, 2021, 11:30:39 pm
content: I think the numbers originally came from Hakko products.
History of 3-phase Electricity & Distribution - Page 1
Forum section: electronics / general

author: Homer J Simpson
author_rank: Super Contributor
timestamp: January 05, 2022, 11:58:29 pm
content: Interesting video on the early development of 2 and 3 phase AC and motors.

author: armandine2
author_rank: Frequent Contributor
timestamp: January 07, 2022, 12:05:39 pm
content: My current favourite youTuber - once you get over her hand waving - great content and presentation.
Electronics people and/or meetups in Skåne - Page 1
Forum section: electronics / general

author: Gerharddc
author_rank: Newbie
timestamp: December 31, 2021, 09:10:26 am
content: I have recently moved to Sweden, specifically Lund, to become the only (for now at least) "hardware guy" at a small software company. As all my friends who share a passion for electronics ( so all my friends basically) are now half way around the world, I would like to make some new ones closer to home. I am thus curious to find out if there are any meetups in the Skåne area for electronics people, or even individuals open to meeting up.

author: SM3VLC
author_rank: Newbie
timestamp: January 01, 2022, 08:39:09 pm
content: The Swedish Electronics Forum (https://elektronikforumet.com/forum/) would be a good place to go to find out.There you will have a better chance to reach your target audience.I live further north so I'm not sure about how many active people there are in the area.
Need help finding schematic for PZ-DSP28335 - Page 1
Forum section: electronics / general

author: donotdespisethesnake
author_rank: Super Contributor
timestamp: December 28, 2021, 07:59:06 pm
content: I bought a cheap PZ-DSP28335 dev board from a seller on ebay, but they are unable to provide a schematic. I tried to find a schematic on google, but all the sites I can find need some knowledge of Chinese. I think one site has the schematic (http://m.elecfans.com/article/1179802.html), but it looks like it needs a login and google is unable to translate the page.I know it's a long shot, but does anyone happen to have a schematic for his board? Or maybe someone could do me a big favor and find a way to download the schematic from one of the Chinese websites?TIA
Closed-loop NEMA34 stepper motor - Page 1
Forum section: electronics / general

author: xzswq21
author_rank: Frequent Contributor
timestamp: November 08, 2021, 06:20:06 pm
content: HelloI need several Closed-loop stepper motors with driver for a CNC machine. Holding Torque of 3 N.m is enough but it should bereliable(the accuracy is important for my work, I want to produce precision things). Do you know a reliable closed-loop NEMA 34 stepper motor?(The power supply is 48VDC but I can use an AC power supply)Thanks

author: ajb
author_rank: Super Contributor
timestamp: November 09, 2021, 02:44:52 am
content: Any stepper (or any other kind of motor) can be closed loop with the addition of an encoder and a suitable driver. At that size there are plenty of options, including all-in-one servo systems, some that even have on-board motion control, ranging from cheap eBay stuff to components that are used in real CNC machines with eye watering price tags.You mention reliability in the same sentence as accuracy, but accuracy, reliability, precision, and repeatability are all different but equally important parameters for things like CNC machines, and they're only partially dependent on the motor. The mechanics of the machine are as important or even more. What sort or specs are you after?

author: xzswq21
author_rank: Frequent Contributor
timestamp: November 09, 2021, 04:41:31 am
content: The mechanism is ballscrew and the pitch is 5mm, if I use a 2-phase stepper motor the resolution would be 5mm/200=0.025mm=0.001" and usually the error of a 2-phase motor is +/-5 %. Can I enable microstep function on the driver to have a better resolution for the 2-phase stepper motor? What do you think about Leadshine stepper motors? Thanks

author: NiHaoMike
author_rank: Super Contributor
timestamp: November 09, 2021, 04:52:29 am
content: Trinamic ASICs can drive stepper motors as high pole count BLDC motors, using sensorless drive to achieve closed loop control.

author: xzswq21
author_rank: Frequent Contributor
timestamp: November 09, 2021, 06:05:23 am
content: Quote from: NiHaoMike on November 09, 2021, 04:52:29 amI checked the website but there are a lot of products. I need a STEP/DIR driver for the stepper motors.

author: MarkLiu
author_rank: Newbie
timestamp: December 27, 2021, 05:27:50 am
content: Stepperonlinehas suitable closed-loop stepper motors available, as well as a selection of kits that include a driver and power supply.

author: Foxxz
author_rank: Regular Contributor
timestamp: December 27, 2021, 05:48:46 am
content: Clearpath has pretty nice units with the controller and everything built into the stepper.
Homemade EL segment display - Page 1
Forum section: electronics / general

author: Canis Dirus Leidy
author_rank: Regular Contributor
timestamp: December 26, 2021, 08:45:56 am
content: A man describes his experiments on making homemade electroluminescent indicators:Atext version (in Russian)of this video and abrief (but translated into English) descriptionof experiments with making of indicators.
DSN-VC288 panel V/A meters - frozen after zeroing. - Page 1
Forum section: electronics / general

author: Caaarlo
author_rank: Newbie
timestamp: December 25, 2021, 11:15:36 pm
content: I have just put my hands on these meters after having them resting on a shelf for 3 or 4 years.The worked ok, but wanted to calibrate zero by using the popular procedure:1-power off2-connect a jumper between zeroing pads3-power on4-after some seconds, remove jumper.Well, I did it on one meter, and got some weird result, so I thought it might be a defective unit. Then I tried the same procedure on another unit.. SAME THING !!!After removing the jumper, the display won't return to normal operation, but will remain frozen showing -60V and --0A, no matter what input is present. Already tried zeroing again but nothing happens. The meters are basically bricked. Any solution besides firmware update ? I don't have a programmer for these MCUs.
Radwell's Stupid Outrageous T & M Pricing! - Page 1
Forum section: electronics / general

author: Chris56000
author_rank: Frequent Contributor
timestamp: December 24, 2021, 07:12:16 pm
content: Hi!Can anyone beat this gem from Radwell?! I know of old their prices are a rip–off but they've got to have excelled themselves this time!You could buy TEN BRAND NEW Tek MSOs for less!https://www.ebay.co.uk/itm/TEKTRONIX-475DM44-475DM44-USED-TESTED-CLEANED-/392307981670?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l49286&mkrid=710-127635-2958-0Chris Williams

author: eti
author_rank: Super Contributor
timestamp: December 24, 2021, 07:56:31 pm
content: Quote from: Chris56000 on December 24, 2021, 07:12:16 pmOkay, so don't buy from them, and thus no need to rant and bring yourself down. Happy Christmas!
Helping each other through the chip shortage - Page 1
Forum section: electronics / general

author: blowtorch
author_rank: Newbie
timestamp: December 23, 2021, 05:29:16 pm
content: Hi AllToday I wasted a bunch of time online, trying to find a part that I need. The part is a MCP1640D in SOT23-6 format (MCP1640D-I/CHY).Searching through stock, I found a partial reel of PIC16F1829, and a quick search of the usual places revealed that, that too is out of stock, everywhere. Which means somewhere, someone is looking for this part, which is sitting in my stores, and I bet somebody somewhere has the parts that I need...So, that got me to thinking, should we not have a place where we can all list stuff that we need, and / or stuff that we have that are surplus to requirements, and maybe we can help each other out? Maybe have a dedicated forum / subject / sticky or something here? Or 2 threads, "stuff that is surplus", and "stuff that we need".Thoughts?

author: armandine2
author_rank: Frequent Contributor
timestamp: December 23, 2021, 06:02:32 pm
content: I thought they'd discredited barter as unworkable - not sure that the alternative market process will get you your chips.

author: blowtorch
author_rank: Newbie
timestamp: December 23, 2021, 07:52:02 pm
content: I am not prescribing the mechanism used to give effect to components changing hands. Normal commercial terms are fine.It all comes down to communication. My company does not sell components, rather we buy components and manufacture products, and right now I need a specific chip which is not available anywhere. Somebody must have some sitting on a shelf, left over from a production run that they do not need. And at the same time, we have something that is sold out globally, and somebody must want them. 2 separate issues, I am not trying to combine them, just illustrate the situation. There must be thousands of companies in a similar situation.But how to find each other? It would be great if there was a central place to go to online.

author: thm_w
author_rank: Super Contributor
timestamp: December 23, 2021, 11:14:47 pm
content: Its called Ebay or Taobao.Both locations are selling PIC for ~$1. MCP about $1 but a bit less available.The problem is 99% of companies don't want to source parts from unknown suppliers, so good luck making the sale. Then you are left with the option of selling to a chip broker for pennies, who probably doesn't want to deal with a half reel worth <$1k. Its a lot easier in China where they have many more small size brokers.

author: VK3DRB
author_rank: Super Contributor
timestamp: December 24, 2021, 02:54:45 am
content: This idea would work if many people contributed to it and the database was substantial. It could be a push system, ie: this is the parts I have, or a pull system ie: this is the part I need. Could also only be for EEVBLOG subscribers. Other than that, exorbitant prices and slow shipping from eBay or brokers.
50k fps Slow Motion photography of old 'Vector' style arcade games. - Page 1
Forum section: electronics / general

author: BrianHG
author_rank: Super Contributor
timestamp: December 23, 2021, 03:54:49 am
content: Ok, just interesting to look at old Atari Vector style arcade games filmed at 50k fps.

author: james_s
author_rank: Super Contributor
timestamp: December 23, 2021, 05:06:44 am
content: I have a few Atari vector games implemented in FPGAs and those you can easily clock much, much faster or slower than the original clock rate and since the video hardware does not require any specific timing, it can deal with it just fine. Using an analog scope as a display I slowed it down to the point that I could watch the beam dancing around tracing out the various objects on the screen in real time, and then sped it up to about 30x the regular speed, a magnetic deflection vector monitor wouldn't have kept up with that but the scope can.

author: Picuino
author_rank: Super Contributor
timestamp: December 23, 2021, 10:01:22 am
content: Games based on vectors on the screen instead of pixels have always caught my attention. In my case one of the first ones I played was the asteroids.

author: james_s
author_rank: Super Contributor
timestamp: December 23, 2021, 07:12:09 pm
content: Unfortunately that clip (as with most) is from an emulator and does not even begin to do justice to Asteroids. I just took a quick video of my cabinet, it's hard to hold the camera and play one-handed but you can get at least an idea of how the real deal looks. This game makes arguably the best use ever of the unique capabilities of a vector display. The dynamic range is incredible with those blinding white missiles on an inky black background.https://youtu.be/iSRS2-qJJsA
Question cable joystick snes - Page 1
Forum section: electronics / general

author: tiago1986
author_rank: Regular Contributor
timestamp: December 22, 2021, 04:11:54 pm
content: I have Snes console joystick controls and the cable is dry hard rigid any solution for the cable to go back to being soft and flexible?

author: Benta
author_rank: Super Contributor
timestamp: December 22, 2021, 07:41:31 pm
content: Nope.Getting the softening agents back into the polymers is not really possible.A new cable is the way to go.

author: tiago1986
author_rank: Regular Contributor
timestamp: December 23, 2021, 11:45:25 am
content: I wanted to recover these joystick controls because they are expensive and original and it is not easy to open the control because the screws are small and rusty
What happens when you re-use tracking numbers but don't refresh the database - Page 1
Forum section: electronics / general

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: December 22, 2021, 10:43:51 pm
content: I've always wanted to go!

author: jpanhalt
author_rank: Super Contributor
timestamp: December 23, 2021, 12:20:40 am
content: That happens. A few years ago, I bought an auto part (a piece of trim, about $200) from a shady (known only in retrospect) company in Florida. It was defective, and I returned it. The replacement part was just as defective. Returned it, but accidentally attached the wrong USPS label to the package. Realized it almost immediately after submitting it to the Middleburg, OH P.O. Figured it would let me swap labels. I could see the box from the counter. No way. It was still delivered, but the tracking showed the original delivery.One thing I learned is that defective parts are not always returned to the manufacturer. In that case, it was a Ford part. They make it into a grey market. Ford lets them be resold. The original authorized dealer passed it on the the shady dealer. Second, my credit card saved me. In the end, I found a truly authorized dealer and got a good part. Third, be very careful to know whether you are dealing with the actual company or an "authorized reseller." If you look at Verizon (an unrelated example), there are "Verizon stores" and "authorized resellers." Verizon may not stand behind what an authorized reseller sells.
Interesting vid on history and tech of nixie tubes - Page 1
Forum section: electronics / general

author: MK14
author_rank: Super Contributor
timestamp: December 23, 2021, 01:08:37 pm
content: I've only watched the first minute and 10 seconds (approx, I'm looking forward to watching the rest). But have to say, it looks a very interesting video, or set of them. Thanks for posting this.Also, spoiler alert. There is a tiny, tiny connection to EEVBLOG, in the first minute.
How does "Yun Express DDP" compare with "Registered Airmail" (Elecrow) ? - Page 1
Forum section: electronics / general

author: 741
author_rank: Frequent Contributor
timestamp: December 20, 2021, 11:51:52 am
content: I generally pick "Registered Airmail" for Elecrow orders to the UK and so far it has worked fine. In particular I do not get the demand for a 'disbursement fee' which occurs for DHL, TNT, FedEx etcThis time I noticed that Registered Airmail = 20-60 days, $9.76 but "Yun Express DDP is faster (something like 11-16 days) & cheaper ($6.13).I was tempted to try Yun Express DDP, but opted for 'what I know' this time.Has anyone out there used the Yun Express DDP service to the UK, and are there any known disadvantages compared with Registered Airmail?

author: thm_w
author_rank: Super Contributor
timestamp: December 20, 2021, 10:36:52 pm
content: https://www.yunexpresseu.com/product-and-service/DDP means duty prepaid. End delivery will likely be performed by normal royal mail, or maybe a local courier.How long does registered airmail normally take? For Canada at least, these DDP services are a lot faster, a few weeks vs 1+ months.

author: 741
author_rank: Frequent Contributor
timestamp: December 21, 2021, 10:02:03 am
content: Typically, an order with Elecrow (delivered by registered airmail) is here within 3 weeks.
Pi 4 (4GB) + Pi 400: a good time to sell? - Page 1
Forum section: electronics / general

author: eti
author_rank: Super Contributor
timestamp: December 21, 2021, 01:41:46 am
content: I've just read news that the Pi 4 (4GB) and Pi 400 are very limited in supply. I have one of each, both of which are mint, and currently unused. Is this a good time to sell?Thanks.

author: MK14
author_rank: Super Contributor
timestamp: December 21, 2021, 01:54:35 am
content: https://thepihut.com/products/raspberry-pi-4-model-b?variant=20064052740158Seem to have them in stock, for £54 including VAT, and the PI 400 (KIT), seems to be the same price from Amazon UK, it has been for quite a long while now (Just over £90, but includes all the fiddly bits you need to set one up, such as Leads, PSU, SD card, and stuff).https://www.amazon.co.uk/Raspberry-Pi-Official-Start-up-Layout/dp/B08Q5YFM9CIf you don't want them, then I guess sell them. But if you want to make lots of money .......

author: Refrigerator
author_rank: Super Contributor
timestamp: December 21, 2021, 02:42:13 am
content: Quote from: eti on December 21, 2021, 01:41:46 amis PiCoin a thing now?

author: SiliconWizard
author_rank: Super Contributor
timestamp: December 21, 2021, 02:48:38 am
content: As MK14 showed, they are available on the pi hut (and a lot of other places) on a regular basis, at least the pi 4 (not sure baout the pi 400). Sure stock varies a lot these days, and the 8GB version seems to be the one hardest to get ahold of. But 4GB versions are relatively easily available. Anyone willing to pay more than the official price, at this point, would be an idiot. Unless they are in a big hurry and it happens not to be in stock just the day they want to order it.

author: eti
author_rank: Super Contributor
timestamp: December 21, 2021, 04:04:13 am
content: I'm simply asking if I'd get a fair price. I am all for making a living, but never a *killing*. If I got RRP or thereabouts, I'd be happy. There's more to life than money.
Where can I get this "foam" gasket material? - Page 1
Forum section: electronics / general

author: xrunner
author_rank: Super Contributor
timestamp: December 20, 2021, 02:18:18 pm
content: It's used on many things such as the gasket inside the screw-on cap of a spray bottle. It's also on the inside of my alcohol dispensing container bottle and other types of plastic bottle caps. I need to make some more to fix some bottle leaks. I cannot find this in a craft store. It's 1 mm thick. It isnothard plastic, it's some type of foam.Does anyone know what it's called and where I can get a sheet of it (I'll make my own gaskets from the sheet).Thanks.

author: jpanhalt
author_rank: Super Contributor
timestamp: December 20, 2021, 02:52:37 pm
content: Like this:https://www.usplastic.com/catalog/item.aspx?itemid=122875By look and feel, it is a high density PE (or PP) foam that is slightly resilient and chemically resistant. Finding it in larger sheets, if that is what you want, may be difficult. At least that is a lead. I have dealt with that company before. The largest that link shows is 12 cm. Is that big enough to cut what you need?

author: xrunner
author_rank: Super Contributor
timestamp: December 20, 2021, 03:15:07 pm
content: Quote from: jpanhalt on December 20, 2021, 02:52:37 pmHey thanks! Your link called them "foam cap liners". With that search term, I found some on Ebay, in different diameters. I can cut them if I need to.Just needed a good search term.Thanks!

author: radar_macgyver
author_rank: Frequent Contributor
timestamp: December 20, 2021, 03:29:36 pm
content: McMaster calls it closed-cell foam, they have it in a variety of thicknesses too.https://www.mcmaster.com/foam/food-industry-super-cushioning-polyethylene-foam-sheets/
What in the bodge work is this? - Page 1
Forum section: electronics / general

author: JustMeHere
author_rank: Frequent Contributor
timestamp: December 29, 2021, 07:38:52 pm
content: Saw this in an ad today. Note the "smd" work in quadrant 3.https://us.digiprint-supplies.com/en/ultra-4000-pci-card-pbowi17591?fbclid=IwAR1zbW6SFxINQtAyC5A2wqzMCFBVSxCOsiglTdEWln6iZQ4Q78WjpCE93sI

author: Martin Miranda
author_rank: Regular Contributor
timestamp: December 29, 2021, 07:56:19 pm
content: management stuff.