hybridfree/eevblog-posts huggingface dataset:
What is a 4P4C modular connector really called? - Page 1
Forum section: electronics / projects

author: gcewing
author_rank: Regular Contributor
timestamp: August 13, 2023, 02:49:31 am
content: From what I can tell, officially "RJ11" refers to a 6P2C modular connector . But I've also seen 4P4C connectors referred to as RJ11 on some vendors' sites. Is this incorrect? Does 4P4C even have an RJ number?

author: wraper
author_rank: Unknown
timestamp: August 13, 2023, 02:58:17 am
content: RJ9

author: gnuarm
author_rank: Super Contributor
timestamp: August 13, 2023, 07:11:57 am
content: Quote from: gcewing on August 13, 2023, 02:49:31 amI'm not sure which connector you are referring to. The 4P4C would be the handset connector I believe. The jack/plug for the phone line has 6 positions and often has 4 wires on the jack. Only phones with two line capability would have 4 wires on the corresponding plug. But then the cable is separate from the phone itself, so it's really the jack on the phone that would be 6P2C or 6P4C.4P4C is never RJ11.It's hard to keep this stuff straight.

author: gcewing
author_rank: Regular Contributor
timestamp: August 14, 2023, 03:02:45 am
content: Yes, it's the handset connector.If I understand correctlyl it doesn't really have an RJ number at all, probably because it's not used for phone lines.Someone needs to explain this to Jaycar. They have a bunch of 4P stuff marked as "RJ11"!
what is a indian bead? - Page 1
Forum section: electronics / projects

author: coppercone2
author_rank: Super Contributor
timestamp: October 04, 2024, 07:15:08 pm
content: my hp meter has a 'indian bead' specified in the errata. It disintegrated during disassembly.Is this just a insulator? It says it prevents the ferrite from touching the case. But does it do anything RF wise?

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: October 04, 2024, 07:30:21 pm
content: Have not hear them called "indian" but I have seen small plastic beads used as insulators or spacers in some old HP equipment. The ones I saw are hard and almost clear. Definitely just insulators or spacers.

author: Stray Electron
author_rank: Super Contributor
timestamp: October 04, 2024, 07:49:35 pm
content: Quote from: coppercone2 on October 04, 2024, 07:15:08 pmIt sounds like a plain plastic bead that was used to space the base of a part (such as a power transistor) up and away from the metal chassis or through the CENTER of a larger hole in a metal heat sink. If so then it shouldn't have any effect on the circuit.I've never heard the insulators called Indian beads but I'm sure that that is a reference to the brightly colored European manufactured beads that the early Dutch, French, Spanish and English traders used to trade to the American Indians.

author: floobydust
author_rank: Super Contributor
timestamp: October 04, 2024, 07:55:19 pm
content: That it disintegrated implies it was organic?I go to the local hippy bead store if I need spacers. Most are glass.

author: TimFox
author_rank: Super Contributor
timestamp: October 04, 2024, 08:03:30 pm
content: Sometimes the spacer beads are ceramic, if temperature is a problem.Here is an Indian source for what are normally called "fish-spine" beads (because of how they stack for longer wires):https://in.misumi-ec.com/vona2/detail/222005942938/?HissuCode=RG-4#These beads allow reasonable flexing for a wire inside them, as the curved surfaces articulate.

author: coppercone2
author_rank: Super Contributor
timestamp: October 04, 2024, 09:53:14 pm
content: it looked like a blue doughnut and it cracked into many pieces is what I mean. I thought it was glass-like. Fell on the floor somewhere as usualI can just cut a segment of teflon tube instead if its just a insulator. I thought it might have been a complimentary ferrite typeI never saw multiple materials stacked up together, but its possible

author: Sacodepatatas
author_rank: Regular Contributor
timestamp: October 04, 2024, 11:52:03 pm
content: Maybe nothing to do, but some months ago I'd read the english version of a chinese paper about a MCU core and then I saw SFR_Indian_Addr. Maybe it was a bad translation of the SFR_Indirect_Addr label in chinese.

author: 44kgk1lkf6u
author_rank: Regular Contributor
timestamp: October 05, 2024, 03:25:51 am
content: If it is not attracted to magnets, then it is not ferrite.
What is a relay with 'LTB' - Page 1
Forum section: electronics / projects

author: splin
author_rank: Frequent Contributor
timestamp: February 20, 2020, 05:06:12 pm
content: I'm pretty sure I don't need one but I am just curious as to what the LTB means - from the picture it looks like a test button but what is it used for?https://www.lmentesale.com/index.php?main_page=product_info&products_id=173593 I did read the datasheet but it wasn't enlightening

author: splin
author_rank: Frequent Contributor
timestamp: February 20, 2020, 06:52:35 pm
content: Quote from: blueskull on February 20, 2020, 05:51:37 pmOk, thanks, but what does it do when you press the test button - does it operate or release the relay? Where and why would you use one?

author: I wanted a rude username
author_rank: Frequent Contributor
timestamp: February 21, 2020, 02:09:25 am
content: Fromthe Finder 60-series datasheet(emphasis added):The dual-purpose Finder test button can be used in two ways:Case 1) The plastic pip (located directly above the test button) remains intact. In this case,when the test button is pushed, the contacts operate.When the test button is released the contacts return to their former state.Case 2) The plastic pip is broken-off (using an appropriate cutting tool). In this case, (in addition to the above function),when the test button is pushed and rotated, the contacts are latched in the operating state, and remain so until the test button is rotated back to its former position.To answer your second question, it would be implementation-specific, but could ease testing since the operator could set the relay on and go investigate downstream.

author: splin
author_rank: Frequent Contributor
timestamp: February 21, 2020, 06:48:06 pm
content: Quote from: I wanted a rude username on February 21, 2020, 02:09:25 amThanks, that makes sense. The Schneider datasheet I looked at was silent wrt the TLB. It seems that the 'L' should stand for latching/latchable more than lockable then - I assumed the latter meant it could be phsically locked for safety purposes, but clearly not.
What is a suitable replacement for a PBSS5160T transistor? - Page 1
Forum section: electronics / projects

author: vinicius.jlantunes
author_rank: Regular Contributor
timestamp: October 29, 2015, 07:05:56 pm
content: I am repairing a board and need to replace one of these transistors:http://www.nxp.com/documents/data_sheet/PBSS5160T.pdfAs far as I can tell it's not just a regular PNP transistor, it has lower than normal VCESatvoltage, so it dissipates less power when operating in saturation. I guess I could get away with using a regular PNP transistor (with same voltage / peak current ratings) but am not quite sure... hence the questions:1) can I just use a regular PNP transistor in its place?2) if not, what could be suitable replacements?Reason I ask is that sourcing such parts in Brazil is nearly impossible without paying through the nose in import fees and freight. If there was some more "jelly bean" kind of part I could use, the odds of actually finding it for purchase are greater.Thanks in advance.EDIT: link to the repair thread for those interested / looking for contexthttps://www.eevblog.com/forum/repair/tv-power-supply-kpsl150c3-01/

author: calexanian
author_rank: Super Contributor
timestamp: October 29, 2015, 07:30:39 pm
content: Thats a tough one. Those low saturation voltage transistors are kinda special. I would just fork over the money and order them.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: October 29, 2015, 07:54:53 pm
content: Maybe 4 x 2N4403 in parallel (with 10 ohm resistor in series with each base?), if you have that handy. Might explode though, dunno.Tim

author: vinicius.jlantunes
author_rank: Regular Contributor
timestamp: October 30, 2015, 12:04:03 pm
content: @AcHmed99: yes, in theory I can order from Farnell, or even Mouser and Digikey, all the "normal" places. Most will send to Brazil, but huge shipping charges, and then I get charged ridiculous import taxes as well by my lovely government.It seems I got lucky though - I learned a friend of mine is visiting the US at the moment, so looks like I will be able to get the exact replacement sent to him and then he brings it to meOnly question now is what other goodies to add to my Digikey order to make the shipping costs worthwhile. By the way, Digikey uses to have the most cost effective shipping costs right? Like 20 bucks for up to 1 pound or something?
What is a teraohm resistor used for? - Page 1
Forum section: electronics / projects

author: MildInductor
author_rank: Regular Contributor
timestamp: July 01, 2024, 04:13:20 am
content: My question is pretty much the title. I was browsing Mouser and found a 10 teraohm resistor (588-UM050E100BKE). What could this be used for?

author: daqq
author_rank: Super Contributor
timestamp: July 01, 2024, 04:24:00 am
content: Some applications:High voltage dividersFeedback for transimpedance amplifiers for ultra low currents ( see:https://www.analog.com/media/en/technical-documentation/user-guides/ADA4530-1R-EBZ_UG-865.pdf)Ultra low current sourcesMostly specialized stuff.

author: coppercone2
author_rank: Super Contributor
timestamp: July 01, 2024, 04:36:17 am
content: or bleeding charge from something fairly non conductive. Like a super weak ESD connection. I am sure it has physics uses (so it does not load the device that might have a resistance in the gigaohms)

author: chris_leyson
author_rank: Super Contributor
timestamp: July 01, 2024, 05:35:12 am
content: I've used higher value resistors for electrometer amplifiers in physics experiments using the ME1403 electrometer triode many years ago. The resistors were sealed in large glass tubes to avoid contamination.

author: Kurets
author_rank: Regular Contributor
timestamp: July 01, 2024, 09:44:50 am
content: Not teraohm but I have encountered 100GOhm (from memory, might have been slightly different value) used in a current source for measuring plasma density around a spacecraft.

author: Phil1977
author_rank: Frequent Contributor
timestamp: July 01, 2024, 10:31:39 am
content: Imagine you build a terraohm meter and want to check/calibrate it somehow.And what do you use a terraohm meter for? E.g. testing insulations. Nearly every insulation is a little conductive. If you can track changes of this unwanted conductivity far before it gets a problem, you can early detect aging or any kind of stress. That´s only one example from quality control where you can use these things.

author: MildInductor
author_rank: Regular Contributor
timestamp: July 01, 2024, 10:58:38 am
content: That's all very interesting. Thanks everyone!

author: Phil1977
author_rank: Frequent Contributor
timestamp: July 01, 2024, 11:55:42 am
content: And think about the following: You just need to put 1mA through this resistor, and the voltage drop generates 1GV of potential... But be careful, it´s also dissipating 1MW of heat!With only one mA you have enough heat for 50 houses... That´s fantastic! And don't be so skeptical and say such a current source is difficult. It can't be that hard, it´s just one mA.SCNR
What is amount of current required for p-mosfet when load is not applied?  - Page 1
Forum section: electronics / projects

author: Sai teja
author_rank: Regular Contributor
timestamp: April 11, 2018, 03:01:08 pm
content: Hello, I am using p-channel MOSFET(NTR4502PT1G) in my application in the configuration shown in the image. If 9 V input is absent, p-channel MOSFET (NTR4502PT1G) turns on, and battery power is supplied to entire system if on/off button is switched on.I would like to know the amount of current drawn from the battery when on/off button is turned off, the 9V input is not connected to gate terminal of MOSFET and battery is connected to the source terminal.Please help me in this regard.

author: bson
author_rank: Unknown
timestamp: April 11, 2018, 06:56:05 pm
content: None, because there's no closed circuit.

author: Ian.M
author_rank: Super Contributor
timestamp: April 11, 2018, 07:41:49 pm
content: The datasheet says under 100nA of gate-source leakage.https://www.onsemi.com/pub/Collateral/NTR4502P-D.PDFpage 2 near the top.The battery's self-discharge will dominate e.g an Energizer 522 PP3 9V alkaline is expected to loose 20% of its charge over its five year shelf life. Its capacity is about 600mAH.120mAH/43800H = 2.74uA equivalent self discharge current.
What is an indicator unit? - Page 1
Forum section: electronics / projects

author: Circlotron
author_rank: Super Contributor
timestamp: August 08, 2017, 07:43:10 am
content: Picture is from a 1954 magazine. Some kind of WW2 device. Maybe something to do with aiming big guns or dropping bombs or some other kind of bad manners?

author: MK14
author_rank: Super Contributor
timestamp: August 08, 2017, 07:52:51 am
content: It might be this:https://airandspace.si.edu/collection-objects/indicator-radar-interrogator-bc-929-anapn-2-rebecca-mk-iia

author: Benta
author_rank: Super Contributor
timestamp: August 08, 2017, 09:31:37 am
content: "Indicator" simply means display, in this case the rotating cathode-ray display for radar you see in old movies. Rebuilding it to be a 'scope as they suggest would be possible.

author: drussell
author_rank: Super Contributor
timestamp: August 08, 2017, 02:06:47 pm
content: Quote from: Benta on August 08, 2017, 09:31:37 amNope, it certainly wouldn't be the rotating radar type display. The tube is the totally the wrong type. This unit had a standard 3BP1 tube in it which is a 3" tube with electrostatic H and V deflection plates and the standard P1 green phosphor that has relatively short persistence used on early oscilliscopes and computer monitors.Many radar tubes would need a longer persistence phosphor, though the "rotating" ones you're thinking of (like a 3CP1, introduced in 1941 which is electrically the same as a 3EP1 but with the radial deflection electrode, or the later 3DP1 which is otherwise electrically the same as the 3BP1) have the same normal green P1 phosphor but are constructed differently than X/Y tubes with their horizontal and vertical plates and instead have a radial deflection electrode.From Peter Keller's "The Cathode-Ray Tube" book:Quote
What is an injection channel used for in a SAR A2D? - Page 1
Forum section: electronics / projects

author: SuzyC
author_rank: Frequent Contributor
timestamp: September 07, 2014, 08:10:21 pm
content: The PSoC4 MCU's have SAR's that have multi-channel input and one injection channel.ummm...whats that for?

author: nuno
author_rank: Frequent Contributor
timestamp: September 07, 2014, 08:33:32 pm
content: They explain that in one of the docs. Basically and if I remember correctly, you can have the ADC automatically doing readings round-robin on a set of channels. It happens that sometimes you want to do an odd reading on channel which is not part of the set, or a channel you want to just read at a much lower pace; the hw allows you to do this, to inject a one-time "foreign" channel reading in the reading loop programmed in the hw.

author: SuzyC
author_rank: Frequent Contributor
timestamp: September 07, 2014, 10:04:08 pm
content: Thanks nuno, for the explanation, it will help me to work with this a2d module.
What is best distributor to by from if you are in Brazil? - Page 1
Forum section: electronics / projects

author: Isaac Newton
author_rank: Contributor
timestamp: October 20, 2012, 12:29:35 am
content: Hi, guysI'm working on a project and i'm a little bit stuck with the purchasing of the parts for the prototype, especially the PIC (pic16f1828) microcontroller i'm going to use, which is not available anywhere.I'm brasilian and buying anything from other country is a huge pain in the ass! I mean, here we have all kinds of governamental taxes. Because of that, making a prototipe is extremely expensive. Unfortunately, getting samples from Microship is not possible because the bastards do not sends samples to my city!If any brasilian friend that passed by the same situation, what is the best distributor (digikey, mouser...) to get my parts imported? I mean, I know that I can not scape the taxes and I know that Digikey and Farnell have "direct buy from USA" services, but I've heard that it takes a huge, huge time to arrive and, sometimes, they never arrive (some say that the order "gets lost" - You'll know what i mean for that if you are brasilian), so, what is the best and trusty distributor?

author: mariush
author_rank: Super Contributor
timestamp: October 20, 2012, 02:24:46 am
content: What's so special about that PIC that it has to be THAT one?Just on a brief parametric search, PIC16F1933, PIC16F1936, 1938 should have all the features that PIC has, it's just a 28 DIP instead of 20 DIP ... aka it has more pins.Yeah, I know how it is when you're in some countries... even as far as a few years ago here in Romania it was the same thing.. nowadays it's much easier with farnell and rs-components and being in the EU..If you think you'd have luck with stuff sent to you in simple padded envelopes (like pen pal mail, not packages), I'm always up for helping people... so if you want some PIC chip or a few components I'd be willing to order them on Farnell for you and send them through air mail to Brasil for you. It would probably cost you about 3-5$ over the price on Farnell UK, that much would be postage and envelopes and all that.

author: Isaac Newton
author_rank: Contributor
timestamp: October 20, 2012, 04:24:41 am
content: QuoteThe thing is that it is cheaper than the 1933, 1936 and 1938 and the aplication is cost sensitive, and the pinout of this chip is just what i need. Plus, none of the three that you suggested are available in my country...QuoteI don't know if the EEVBlog Forum has any private message service, but I'd like very much to talk to you. I would appreciate very much your help.Thanks for being so helpful.
what is carrier frequency in VFD? - Page 1
Forum section: electronics / projects

author: danjenkins
author_rank: Contributor
timestamp: August 27, 2019, 02:49:01 am
content: I would like to know in more depth what carrier frequency is and its role in VFD.Any guidance would greatly be appreciated.

author: jbb
author_rank: Super Contributor
timestamp: August 27, 2019, 05:32:52 am
content: To vastly simplify, the carrier frequency is the frequency uses to turn the power switches on and off (ie it’s like PWM frequency).It depends a LOT on power- small drives (<100kW) will be in the 4kHz - 16 kHz range and likely use Space Vector PWM (SVPWM, you can search for it online).- Drives 1000 kW and over drives might be 400Hz - 1kHz. At these frequencies SVPWM doesn’t work too well, and other schemes such as Optimal Pulse Pattern control are used. One particularly twisty extension of this is Model Predictive Pulse Pattern Control (caution: vector diagrams and considerably implied mathematics).- Drives over 30000 kW might be thyristor based and go at line frequency (50 - 60 Hz). I’m not sure what the current favourite is for controlling these.

author: MagicSmoker
author_rank: Super Contributor
timestamp: August 27, 2019, 11:22:11 am
content: @jbb's answer is mostly correct, I would just emphasize that a VFD with a fixed carrier frequency implies a lower frequency sinusoidal reference is modulating the duty cycle of a higher frequency square wave (the carrier). Typically (if not exclusively), this means the VFD employs a scalar (V/Hz) control scheme, rather than a vector (field-oriented) control scheme.Note, also, that space-vector pulse width modulation is a switch control scheme that maximizes the use of the available bus voltage and not a motor control scheme, per se. So you could theoretically have a drive that uses a scalar motor control scheme with SVPWM, but it would be most unusual to say the least; carrier-based PWM is far more likely in such a case. In contrast, many older drives use a field-oriented motor control scheme with carrier-based PWM, so that combination is quite common.@jbb - the venerable old thyristor-based cycloconverter is still commonly used at the very high power level, though it is being supplanted by the matrix converter.

author: jbb
author_rank: Super Contributor
timestamp: August 28, 2019, 09:20:11 am
content: Thanks MagicSmoker, that does clarify things a bit. I skipped over some stuff.At Medium voltages (say 2kV and up), Modular Multilevel Converters (MMC) are starting to make inroads. But they are quite complicated... I think the thyristors will be safe for a while yet

author: lukebarber
author_rank: Newbie
timestamp: August 28, 2019, 01:09:15 pm
content: 20 kHz is common for a variety of reasons.1) The frequency is above the audible band.2) Power devices have been optimized for this frequency.3) The switching frequency is high enough to allow reasonably high current loop bandwidths-1-2 kHz.4) Noise suppression components are smaller.Here's a good post on selecting VFDs.https://precisionautomation.net/2016/01/27/how-to-choose-the-right-control-method-for-vfds/
what is considered good for rack mount ? - Page 1
Forum section: electronics / projects

author: coppercone2
author_rank: Super Contributor
timestamp: November 15, 2019, 06:42:43 am
content: So the world of rackmount is pretty large and new to me.I want to put 19 and 17 inch equipment on racks. It does not even need to be screwed in (I am careful), so more like slide in shelves.What is considered a good value for racks? I don't mind drilling holes, I really just want the frame so I can put painted angle irons into it. Is there a cheap manufacturer that will sell a heavy aluminum frame with casters, with 4 supports ( I don't like balancing the equipment in the middle around a beam).I am worried about buying thin stuff on ebay that is bent, I was hoping for an extruded aluminum frame with an aluminum base. I have too much random equipment sizes (amplifiers etc) to bother mounting, not to mention its old stuff so a fast 'jettison' is nice.

author: I wanted a rude username
author_rank: Frequent Contributor
timestamp: November 15, 2019, 07:07:18 am
content: Is this for servers or comms equipment? The racks for both are significantly different.There's a constant stream of surplus racks on eBay. Often for a few hundred bucks, sometimes pretty much free. If your equipment has its own rails, this is the best option. You can also use shelves, but they don't look as nice. Short and light equipment can just bolt to the front row of holes.One thing to factor in though is that, with the exception of the much shallower comms-style racks/cabinets, racks are physically large, and will dominate almost any room they're put in.

author: radar_macgyver
author_rank: Frequent Contributor
timestamp: November 15, 2019, 07:17:47 am
content: Starcasemakes some inexpensive open-frame racks. The nice part is they sell as a kit with different height rails.
What is differential ADC equation? - Page 1
Forum section: electronics / projects

author: SebG
author_rank: Regular Contributor
timestamp: May 10, 2013, 10:53:26 pm
content: I'm working with PIC16F1783 MCU that has a differential 12-bit ADC.I would like to know the equation that uses Vin+, Vin-, Vref+ and Vref- parameters to get the digital code.No need to include rounding to the nearest LSB?

author: c4757p
author_rank: Super Contributor
timestamp: May 10, 2013, 11:01:20 pm
content: Seriously? It's right there in the datasheet, under "ADC Transfer Function".

author: SebG
author_rank: Regular Contributor
timestamp: May 10, 2013, 11:10:16 pm
content: I'm exhausted right now and my brain is on power saver mode i guess. Still what is the mathematical equation?

author: c4757p
author_rank: Super Contributor
timestamp: May 10, 2013, 11:17:05 pm
content: floor((?Vin/?Vref)*FFFh + 0.5)Dammit, forum! "?Vin" should be "Delta Vin".
What is DT type relay transfer time? - Page 1
Forum section: electronics / projects

author: Miyuki
author_rank: Frequent Contributor
timestamp: November 05, 2023, 02:27:43 pm
content: Hi folks,just wondering, are there any generic values for how long it takes for a Double-Throw relay to transfer from one side to the other?I do not mean that coil delay, but a true switching event.Use scope is switching load between two unsynchronized AD power sources.

author: CaptDon
author_rank: Super Contributor
timestamp: November 05, 2023, 02:51:44 pm
content: 5 milliseconds up to about 50 milliseconds is typical and depends mostly on the size of the relay or contactor. What voltage and current are you switching? If you get contact arc-over during switching you could be creating a shorting path between the two unsync'd A.C. circuits which could be a huge issue if you were switching 480VAC 3 Phase. That is often done with a safety interlocked pair of relays to create a forced break before make with the time delays of dropout to pull-in arranged to provide an absolutely safe dead time during change over.
what is edgewinding, and are there tonal differences between aluminum and copper - Page 1
Forum section: electronics / projects

author: Deactivated-1
author_rank: Frequent Contributor
timestamp: March 14, 2022, 01:01:36 pm
content: so I see on some 'professional' guitar speakers where it says "edgewound ribbon with aluminum wire" on many, is edgewinding just where the turns begin from the edge of the bobbin?and also, is there some major tonal difference between aluminum and copper wire? I read online that aluminum since it weighs less will be more sensitive and have a higher frequency response, but that's for hifi speakers, maybe there's some other difference that makes it sound different in a guitar amp?

author: CaptDon
author_rank: Super Contributor
timestamp: March 14, 2022, 01:43:03 pm
content: If you had two otherwise identical speakers and one voice coil was wound with aluminum and one with copper and we assumed the aluminum was lighter (not necessarily the case however) the aluminum voice coil could be 'faster' with a slight increase in upper usable frequency range. Since no one I am aware of makes the same identical speaker with choice of voice coil winding options we can't really offer a real-world comparison. Any difference would also show up in the T.S. parameters if such an option was available. Aluminum 'ribbon wound' seems to be very popular for speakers in the higher power ratings. I have had one speaker in a monitor cabinet the drove me crazy, it was intermittent at low levels at the beginning of a gig, but if you hit it hard with power it would 'heal' itself for the rest of the night and then not work the next day again. It was the type of speaker with aluminum frame that could easily be disassembled for inspection and repair. The bonding weld of the two different metals where the aluminum voice coil was bonded to the copper wires that lead to the flex wires had failed but would apparently weld itself together after a heavy hit until it cooled back down overnight.

author: JDubU
author_rank: Frequent Contributor
timestamp: March 14, 2022, 02:41:42 pm
content: Edge vs round winding:

author: TimFox
author_rank: Super Contributor
timestamp: March 14, 2022, 03:49:34 pm
content: In a different application, I built a laboratory electromagnet where flat wire in an edge-winding configuration similar to that in the previous reply was used for more efficient heat conduction from the conductor to the outside.

author: CaptDon
author_rank: Super Contributor
timestamp: March 14, 2022, 04:16:58 pm
content: I believe there are some that are 'ribbon wound' that resemble the coiled guts of a tape measure?
What is electrical symbol for 2-coil latching relay? - Page 1
Forum section: electronics / projects

author: prasimix
author_rank: Unknown
timestamp: November 18, 2020, 11:05:47 am
content: For the first time I get the opportunity to use a dual coil latching relay. It turns out that I can't find an electrical symbol for it.There are various collections of symbols on the net but I have not found what I need.

author: Zero999
author_rank: Super Contributor
timestamp: November 18, 2020, 11:44:01 am
content: What are you looking for? A Google image search for dual coil latching relay, brings op plenty of hits.https://www.google.com/search?q=dual+coil+latching+relay&client=firefox-b-e&source=lnms&tbm=isch&sa=X&ved=2ahUKEwj2hOHPgYztAhWHTcAKHVl5CnoQ_AUoAnoECBUQBA&biw=1280&bih=860

author: prasimix
author_rank: Unknown
timestamp: November 18, 2020, 11:45:52 am
content: You're right there is a plenty of them, but I cannot find a "pattern", a standardized symbol.

author: serg-el
author_rank: Regular Contributor
timestamp: November 19, 2020, 02:19:43 am
content: https://studopedia.org/11-99696.htmlGoogle translator to help!

author: vu2nan
author_rank: Contributor
timestamp: November 19, 2020, 07:23:11 am
content: Here's one.
what is in a time percentage dial controller? - Page 1
Forum section: electronics / projects

author: coppercone2
author_rank: Super Contributor
timestamp: June 01, 2025, 10:02:06 am
content: My kiln had this tech before the retrofit. It is a misc box that has a dial on it which you set so it works like a sort of PWM circuit with a fixed frequency (low)I thought it was electronic at first with something like a RC circuit and a relay but I suspect that it might be mechanical.Its not a thermostat because you could hear it click based on the settings and it was not connected to the kiln temperature sensor.How do these work? Or is there a RC circuit in there?I don't know where it is anymore. Maybe thrown out. I have PID on it now. And this one is like from the 70's

author: reodor
author_rank: Contributor
timestamp: June 01, 2025, 10:14:32 am
content: It could be something similar to a simmerstat. It is like a thermostat, but the thermal sensing comes from a separate, low power, heating element. When the switch is on, the heating is on. The tension on the bimetallic element determines how long it takes before it gets hot enough to turn off again.The Youtube channel "Technology Connections" has a video about them:

author: DaJMasta
author_rank: Super Contributor
timestamp: June 01, 2025, 03:54:44 pm
content: If it really is a time interval based thing with no feedback, it could work like a simple mechanical timer - a continuous source of motion that slowly rotates and switches when past the dialed in location. You could do the same electronically and easily, it's basically pwm as you say but where the base resolution is on the order of seconds or more and a complete turn of the dial is a single period.

author: coppercone2
author_rank: Super Contributor
timestamp: June 04, 2025, 07:16:17 am
content: So you think it can be a motor? I was starting to think thermomechanical oscillator. Its too light for a motor. I recall it was really light. must be the same as the video IMO

author: Zero999
author_rank: Super Contributor
timestamp: June 04, 2025, 12:55:54 pm
content: Quote from: coppercone2 on June 04, 2025, 07:16:17 amI encountered a similar device in an old microwave oven. It's a cam timer activating a switch. Why do you think it's too light to be a motor? There are very small motors, such as those used in clocks. The winding is similar to a relay.
what is latch-up of a MOSFET? - Page 1
Forum section: electronics / projects

author: kody
author_rank: Contributor
timestamp: November 30, 2014, 02:15:44 am
content: Mosfet property

author: T3sl4co1l
author_rank: Super Contributor
timestamp: November 30, 2014, 06:07:14 am
content: Mmm?MOSFETs can exhibit parasitic bipolar turn-on, and IGBTs can exhibit SCR type latchup. Otherwise...?Tim
What is Odd and Even bus in LVDS display interface? - Page 1
Forum section: electronics / projects

author: muthukural001
author_rank: Regular Contributor
timestamp: August 28, 2019, 05:10:11 pm
content: Hello All,I am reading PTN3460 datasheet to design eDP to LVDS bridge board. In the LVDS side, there are Odd and Even buses. Could anyone tell how it is being used ?Thanks,Muthu

author: Miyuki
author_rank: Frequent Contributor
timestamp: August 29, 2019, 09:27:25 am
content: Higher resolution (1920×1080) displays use two links to transfer data, lower resolution (1280x720) uses just one linkSome high res displays can work with one link in interlaced mode with just one link connected (I have it on one old Dell laptop, can be annoying when you are sensitive to interlacing artifact)
What is receptacle for this male connector? - Page 1
Forum section: electronics / projects

author: kkbb
author_rank: Contributor
timestamp: September 12, 2018, 10:07:44 pm
content: Hello All,I pulled out a webcam from a laptop for this small size. I cannot figure out what female socket I need to get to plug the male connector from this webcam.Any idea about what female socket will work?Digikey does not seem to have any hits on 'JTCT' which seems to be the manufacturer (www.jctc.com.cn)Thanks in advance

author: langwadt
author_rank: Super Contributor
timestamp: September 12, 2018, 10:22:23 pm
content: looks like JST, something like this?https://uk.rs-online.com/web/p/pcb-headers/5151557/
what is that Program  - Page 1
Forum section: electronics / projects

author: jaRON
author_rank: Contributor
timestamp: April 06, 2011, 05:47:19 am
content: what is that Program

author: ziq8tsi
author_rank: Regular Contributor
timestamp: April 06, 2011, 06:14:18 am
content: Quotehttp://www.labcenter.com/products/vsm_overview.cfm
What is the best PCB socket for oscilloscope - Page 1
Forum section: electronics / projects

author: crgarcia
author_rank: Regular Contributor
timestamp: October 29, 2022, 10:38:28 am
content: Hi,I built my first PCB (hobbyist only), and I added some 2.54mm sockets, that I often use for probing with the oscilloscope.The problem I have is that I don't want to be holding the probe, so I usually add some wires and use the GND clip, but this creates large ground loops and add a lot of noise into the scope, which for some measurements is a problem.What other alternative footprints/sockets/... can I use to make it easy to hook the scope, reducing ground loop/noise?Thanks!

author: jonpaul
author_rank: Super Contributor
timestamp: October 29, 2022, 11:00:14 am
content: BNC connector, 1m Zin use Tektronix 10x probesj

author: Someone
author_rank: Super Contributor
timestamp: October 29, 2022, 11:36:53 am
content: How fancy do you want to go? Lecroy:PK1-5MM-107orPK1-5MM-112Beyond that you can do 50ohm direct with an appropriately terminated BNC/SMA/MHF/U.FL
What is the best resource for Learning PID systems using OP-AMPS - Page 1
Forum section: electronics / projects

author: Arsh ahmad
author_rank: Regular Contributor
timestamp: July 27, 2022, 06:45:25 am
content: I am working on some projects that require analog control systems. I need some resources to learn about Basics as well as advanced concepts of Analog control systems.

author: rstofer
author_rank: Super Contributor
timestamp: July 27, 2022, 03:37:57 pm
content: https://electronics.stackexchange.com/questions/528331/build-pid-controllerhttps://www.lehigh.edu/~inconsy/lab/css/ME389/guidelines/ME389_OPA01_TFSynthesis_Guideline.pdfThere are papers and videos all over the Internet. As to which is best? Try some and see.There are a lot of ways to simulate control systems and MATLAB covers it pretty well. This is but one reference:https://www.mathworks.com/matlabcentral/fileexchange/66187-pid-controller-simulatorKatKim is a pretty good series. Google for: 'katkim control systems'
What is the best way to make an AC chopper and a DC chopper circuit? - Page 1
Forum section: electronics / projects

author: Michael George
author_rank: Contributor
timestamp: October 05, 2016, 01:54:06 pm
content: I'm a student and this is the project of the final year in my collage. I really need your help and advice.I need to make an AC chopper circuit and a DC chopper circuit to control high power load such as: light dimmer (100 W bulb) or Controlling the speed of a small motor or simple resistive load... whatever the load.I need the circuit to be stable and reliable, Not like the circuits that sometimes work and sometimes not.It should work with wide range of loads regardless the temperature and any other factor that can affect the working of the circuit.Would you answer these questions, Please?1. What is the best IC and transistors to make this project? What is their part number?2. Is it better to make it using Arduino and microcontrollers?3. Can I make one circuit that is able to work as a DC chopper and AC chopper? Or Should I make two separate circuits, One for DC chopper and another one for AC chopper?Thank you very much, I really appreciate your help.
SOLVED What is the brand type of this 0.8mm connector - Page 1
Forum section: electronics / projects

author: Kjelt
author_rank: Super Contributor
timestamp: January 07, 2025, 12:39:00 pm
content: Hi all,Searched already in many sellers/manufacturers but can not seem to find/identify this connector ?Dimensions measured with calliper so +/- few % margin.It is used in lighting bricks and lanterns lighting Lego buildings (3rd party), made in China.Thanks!

author: squadchannel
author_rank: Frequent Contributor
timestamp: January 07, 2025, 01:04:33 pm
content: JST SUR?https://www.jst-mfg.com/product/index.php?series=246

author: Kjelt
author_rank: Super Contributor
timestamp: January 07, 2025, 01:09:05 pm
content: Oh man I think you're right.How can I have missed that one, I remember looking at it unable to find 0.8mm but there isThanks !
What is the capacitance of a cermet potentiometer?  - Page 1
Forum section: electronics / projects

author: eV1Te
author_rank: Regular Contributor
timestamp: January 20, 2015, 12:04:48 am
content: I'm doing a project at work which involves driving coils at high frequency (~20 MHz), but we would like to be able to go even higher in frequency without getting into resonance in the coil (we want to be below the resonance frequency) but still have as many turns as possible.The resonance frequency is due to the LC interaction, so we want to minimize the capacitance (inter-winding capacitance is now a few pF) in the system driving and measuring the coils.We have a few trim-potentiometers connected to and from the coils (voltage division), and I was wonderingwhat order of magnitude the capacitance from a multi-turn cermet potentiometer could be?This is not listed in any datasheets and it would also be tricky to measure a capacitance of only ~1 pF in parallel with the resistance of the pot (~100 ohm)

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 20, 2015, 12:52:06 am
content: It'll be typical of size. Supposedly, the smaller SMT ones are good for a few GHz (i.e., capacitance / inductance / transmission line equivalent impedance not very different from the rated resistance and electrical length).Tim

author: c4757p
author_rank: Super Contributor
timestamp: January 20, 2015, 12:59:15 am
content: Quote from: eV1Te on January 20, 2015, 12:04:48 amFor what it's worth, if it'll have an effect on your circuit it should be measurable simply by the nature of the effect it will have. Build something similar to the circuit in which you plan to use it, and try it out.

author: dannyf
author_rank: Super Contributor
timestamp: January 20, 2015, 11:24:07 am
content: QuoteIf so, does it matter to your circuit?
What is the difference beatween  250V marced FUSE and 1000V? - Page 1
Forum section: electronics / projects

author: sorin
author_rank: Frequent Contributor
timestamp: November 21, 2012, 06:38:40 am
content: what is the difference between 250V and 1000V marked FUSE?maybe the minimum separation distance when the fuse blow...

author: Wytnucls
author_rank: Super Contributor
timestamp: November 21, 2012, 07:18:49 am
content: 'The voltage rating of the fuse must be greater than or equal to the circuit voltage.Because the fuse has such low resistance, the voltage rating becomes critical only when the fuse is trying to open.The fuse must be able to open quickly, extinguish the arc after the fuse element has melted and prevent the system open-circuit voltage from restriking across the open fuse element.' (Cooper Bussmann)

author: ejeffrey
author_rank: Super Contributor
timestamp: November 21, 2012, 07:24:54 am
content: Yes. When operating normally the voltage over the fuse will obviously be small. The fuse rating is the maximum voltage the fuse is rated to interrupt.

author: sorin
author_rank: Frequent Contributor
timestamp: November 21, 2012, 07:52:43 am
content: thanks both for answer;I'm not asking why is important the rated voltage on a fuse"To prevent arc you need just a distance of a couple of mm."The question is why (I mean in mechanics construction) fuses with same physical dimension are rated with different voltagewhat is different in 1000v fuse??

author: Wytnucls
author_rank: Super Contributor
timestamp: November 21, 2012, 08:17:19 am
content: Have a look at this:

author: Neilm
author_rank: Super Contributor
timestamp: November 21, 2012, 07:49:52 pm
content: Nice video - showing real sized fuses for a change.Quote from: sorin on November 21, 2012, 07:52:43 amFirstly 1000V fuses are generally bigger. As mentioned in the video, the fuses are filled with sand. The higher breaking capacity fuses will have different sand in them which will quench the extra energy. This is why glass fuses are not used in reputable multi-meters. They don't have sand in them and as the fuse vaporises a high energy source will have enough behind it to continue the arc through the vapourised metalNeil

author: sorin
author_rank: Frequent Contributor
timestamp: December 10, 2012, 03:58:16 am
content: see this
What is the difference between a fuse and an automatic circuit breaker? - Page 1
Forum section: electronics / projects

author: Michael George
author_rank: Contributor
timestamp: July 13, 2016, 10:09:58 pm
content: In other words, Can I use a 10A fuse instead of a circuit breaker?I'm doing this because I can not find a circuit breaker of 10A till now. It is not available for me. I will use a 16A circuit breaker with 10A fuse. Is that OK?Thank you,

author: ebclr
author_rank: Super Contributor
timestamp: July 13, 2016, 10:12:08 pm
content: On the past people used fuses only, go ahead

author: Someone
author_rank: Super Contributor
timestamp: July 13, 2016, 10:56:47 pm
content: They are used for different functions, although they provide the same protection from long term overload (the rated current of the device) they respond differently for short overloads. Below is a comparison of an MCB and a fuse where they both have the same clearing capacity (in DC and AC). Selecting the correct protection is a field all of its own.
What is the difference between 'PCB' and 'Laminate' materials? - Page 1
Forum section: electronics / projects

author: TheUnnamedNewbie
author_rank: Super Contributor
timestamp: July 18, 2022, 03:01:43 pm
content: So talking with packaging houses for BGA packages, they make a distinction between 'PCB' materials (Megtron (Panasonic), Tachyon (Isola), etc) and 'Laminate' materials (E705 (Showa Denko), HL972 (Mitsubishi)). What exactly is the difference? Even when looking at the product pages, they all sell themselves as 'printed wire board materials', and they all seem to come in 'core' and 'prepreg' varieties, as I would expect of a PCB material.

author: ajb
author_rank: Super Contributor
timestamp: July 18, 2022, 04:41:28 pm
content: Presumably there are different properties that are prioritized for materials used in BGA carriers or SOM stackups than for those used in PCBs. Or at least, since you use less material in the than you would for a whole PCB, you're willing to pay more for better performance in some critical areas for the packaging materials. I would guess that such materials prioritize lower warpage (lower/better controlled CTE), maybe higher temperature tolerance for assembly with higher temperature allows, or better chemical compatibility with other materials used in those assemblies.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 18, 2022, 10:58:30 pm
content: Can you get an FAE from each mfg and ask them?Hmmph, probably not, unless you're the fab. And if they're not interested in asking for you..?Tim

author: free_electron
author_rank: Super Contributor
timestamp: July 18, 2022, 11:10:50 pm
content: a laminate is a core with copper applied to it. so you buy this as a ready made "double sided board" and process it as such.you can make your own laminates from raw materials (copper foils and pre-preg)

author: TheUnnamedNewbie
author_rank: Super Contributor
timestamp: July 20, 2022, 07:29:42 am
content: Quote from: free_electron on July 18, 2022, 11:10:50 pmThis is not what I got from the packaging supplier. What I got from there is simply that (at first glance) it seems like the PWB industry is split in two - you have companies doing packaging and those doing PCBs, and as their requirements (and size of final products) are different, there are slightly different requirements for the materials. The precision of etching required for packages is just higher, and so they use more optimized processes and different materials.So in the end there is no fundamental difference, and you have cases where BGAs are made with 'pcb laminates' like rogers or so on.
What is the difference of having type 1, 2, 3 opamp compensator?  - Page 1
Forum section: electronics / projects

author: Patrick66
author_rank: Regular Contributor
timestamp: March 03, 2024, 09:26:33 am
content: Hello everyone, I would like to ask what is the difference between having type 1, 2, 3 opamp compensator for a flyback converter in LED driver? If not mistaken the system of the LED driver in DCM as shown in the figure below is a type two compensator with opamp and optocoupler. Is it possible to build an LED driver in DCM with a flyback converter having a compensator circuit with either type 1 or type 3 compensation? Thank you everyone for your time and guidance.

author: MathWizard
author_rank: Super Contributor
timestamp: March 03, 2024, 07:15:06 pm
content: I've seen some of this stuff but I barely remember it, and I still haven't tried to find the loop gain around any sort of switching circuit with magnetics.Actually I just bought some cheap transconductance amplifier chips, so whatever their spec's will allow, some day I'll experiment with them, and I'll thank myself for already having them.Demystifying Type II and Type III Compensators Using Op-Amp and OTA for DC/DC Convertershttps://www.ti.com/lit/an/slva662/slva662.pdf?ts=1709406965653&ref_url=https%253A%252F%252Fwww.google.com%252F

author: David Hess
author_rank: Super Contributor
timestamp: March 03, 2024, 11:47:09 pm
content: The advantage of type 2 and type 3 compensation is higher bandwidth for better line and load regulation. Type 1 compensation can work, but its bandwidth may be unacceptably low.

author: Konkedout
author_rank: Frequent Contributor
timestamp: March 04, 2024, 12:46:31 am
content: One big hazard of too slow a compensation loop (very likely problem with type 1) is overshoot on turn on. You might briefly get too much current through the LED and damage something before the output settles on its proper value.The design you present sorta looks like type 2 but there are one or two questionable parts in there....