hybridfree/eevblog-posts huggingface dataset:
getting rid of "Hook" and hidden capacitance - Page 1
Forum section: electronics / projects

author: subolg123
author_rank: Contributor
timestamp: May 26, 2014, 08:11:04 pm
content: Came across this little nugget recently. Co-authored by Tektronix, it is certainly interesting from back in the day when circuit board materials ( dielectrics, etc) were not super repeatable or reliable for Tek's critical requirements. It's an interesting read for those who want a historical and technical perspective on what was deemed "hook" and hidden capacitance and it is still there lurking as a potential gotcha for EEs young and old.Enjoy!PS: I had to link the article to my public dropbox folder since it is larger than the 1MB file attachment limit allowed on the forumhttps://dl.dropboxusercontent.com/u/6757916/_Hook%20and%20hidden%20pc-board%20capacitance.pdf

author: retrolefty
author_rank: Super Contributor
timestamp: May 26, 2014, 08:33:37 pm
content: Very interesting document. But as it's dated 1978 I wonder if the PCB material manufactures have 'solved' this variation in production products?P.S. Please don't pass this on to any of the 'golden ear' crowd, we will never hear the end of it.

author: Unknown
author_rank: Unknown
timestamp: May 26, 2014, 09:00:31 pm
content: thanks! ;-)

author: Vgkid
author_rank: Super Contributor
timestamp: May 26, 2014, 09:52:04 pm
content: Interesting read, thanks for uploading it.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 26, 2014, 11:45:19 pm
content: Cool!Wonder how applicable it is today. FR-4 with controlled impedances is standard today, but that's also at much higher frequencies than the article is concerned with. Probably, bargain-basement Chinese suppliers use whatever snotty resin they have available, too.Tim

author: Ian.M
author_rank: Super Contributor
timestamp: June 25, 2020, 01:56:44 am
content: Dropbox link expired, document reposted here:https://www.eevblog.com/forum/beginners/isolated-usb-adapter-or-differential-probe-for-testing-non-floating/?action=dlattach;attach=1006694

author: srb1954
author_rank: Super Contributor
timestamp: June 25, 2020, 06:47:02 am
content: Tek used special circuit board laminates in their oscilloscope input circuits to get round the 'hook' problem. These special laminates were somewhat delicate compared to FR4 and there were warnings in the service manuals not to apply excessive heat or any type of solvent on these circuit boards.

author: TheUnnamedNewbie
author_rank: Super Contributor
timestamp: June 25, 2020, 09:02:09 am
content: So am I correct in understanding that this 'hook' was due to the very long dipole resonance nature of the polymer chains in the resins? This is pretty cool, interesting read, thanks!
Getting rid of Excessive Switching Noise on the Longwei LW-K3010D Bench Supply - Page 1
Forum section: electronics / projects

author: jaxbird
author_rank: Frequent Contributor
timestamp: January 30, 2020, 11:35:37 am
content: It's likely this power supply was designed to use different mosfets with much higher gate capacitance:

author: imacgreg
author_rank: Contributor
timestamp: January 30, 2020, 04:57:01 pm
content: Interesting! Do you have a source (or even just a name) for the plastic binder sheet thing you use for SMD resistor storage?

author: jaxbird
author_rank: Frequent Contributor
timestamp: January 30, 2020, 05:09:38 pm
content: Quote from: imacgreg on January 30, 2020, 04:57:01 pmit's just a book of SMD resistors you can find them on Amazon, eBay and Aliexpress, around $20 each, I find it handy to have 0805 and 0603 resistors plus capacitors.

author: aix
author_rank: Regular Contributor
timestamp: January 30, 2020, 07:24:39 pm
content: Quote from: imacgreg on January 30, 2020, 04:57:01 pmAbsolutely love having those on hand. I bought mine pre-filled with parts (passives or small SMT semiconductors).To look for one, I'd search for some combination of "resistors|capacitor|etc", "0603|0805|etc" and "sample book".

author: vizkoze
author_rank: Newbie
timestamp: March 21, 2021, 01:50:22 pm
content: I just registered an account to report back and say thanks for the instructions.I recently did this modification and it reduced the switching noise from 2vpp to less than 200mvpp (my rigol ds1102ze scope is quite noisy in 10x mode so I don't know if these numbers are correct.)The RMS noise is now acceptable
Getting SMD components' equivalent - Page 1
Forum section: electronics / projects

author: abdulbadii
author_rank: Frequent Contributor
timestamp: October 15, 2021, 03:05:20 am
content: How is the easiest, best way to get SMD components' equivalent, i.e. its ordinary thru-hole components?I need 1N5711W diode as a usual pin/thru-hole one

author: BrokenYugo
author_rank: Super Contributor
timestamp: October 15, 2021, 03:14:12 am
content: 1N5711? Anything starting with 1N is generic diode that's going to come in variety of packages.

author: abdulbadii
author_rank: Frequent Contributor
timestamp: October 15, 2021, 03:29:22 am
content: Gosh, can't believe how naive & ignorant I'm..

author: ocw
author_rank: Regular Contributor
timestamp: October 15, 2021, 04:03:25 am
content: The 1N5711W is not a generic diode, but is rather a Schottky diode. A through hole 1N5711 should work for you.

author: BrokenYugo
author_rank: Super Contributor
timestamp: October 15, 2021, 09:29:45 pm
content: We all have a brain fart sometimes.I use "generic" in the sense that it's a standardized, non proprietary, commodity part.
Getting some value out of the worst thermal camera - Page 1
Forum section: electronics / projects

author: baltersice
author_rank: Regular Contributor
timestamp: March 23, 2018, 02:05:33 pm
content: In spite of all the warnings I got the HT02 thermal camera from China. It isn't even the cheapest one any more, but it sure is bad:Low resolution, long focus range and averaging in software makes it useless for allmicroelectronicintents and purposes.I think it uses a thermopile array sensor, but I didn't find any datasheet for it.I've poked around a bit and found only 2 data lines: Blue goes low every 500 ms, yellow is 2400 varying pulses within every 500 ms window.2400 pulses seem a little bit weird because the spec-sheet claims a resolution of 60*60 pixels. But then again the display is not square, so I could imagine it being a different resolution.But how do they transmit the sensor data? I thought it might be as easy as pulse width representing each pixels value, but there was no noticable change when testing with a hot object.I'll try to figure that out and then do something more fun with that sensor, but if anyone knows something ... lemme know
Getting started with Embedded web server - Page 1
Forum section: electronics / projects

author: jtronix
author_rank: Regular Contributor
timestamp: February 09, 2017, 08:49:48 am
content: Hello,I want to create web server for micro controller based system. I need help to get started with making page and map page variable in code.I have seen TI TM4C1294 examples but in that if any changes needed in web page then it is very complicated to add and modify.Anybody know any other GUI based utility or any other easy way to make embedded server??

author: danadak
author_rank: Super Contributor
timestamp: February 09, 2017, 12:22:20 pm
content: ESP8266, tons of code base, easy to setup. Google it. Lots of videoson Youtube.https://en.wikipedia.org/wiki/ESP8266$ 5 to $ 8 on aliexpress.com for USB version, sub $ 2 for ones without.Regards, Dana.

author: Cupcakus
author_rank: Contributor
timestamp: February 10, 2017, 07:16:07 am
content: I second the ESP8266, the Huzzah module from Adafruit is excellent for prototyping as it's a very particular chip when it comes to voltages and IO, and you can just use it right away. and it comes pre programmed for arduino IDE use right away, then you can use any of hundreds of web server examples on the web for it.
Getting started with ON SEMI AX8052F143 - Page 1
Forum section: electronics / projects

author: Simbarashe Bryne Chipembe
author_rank: Contributor
timestamp: March 28, 2019, 02:23:08 pm
content: Hi Guys,I'm tryna get started with ONSEMI's RF MCU development boards DVK-2c which has an AX8052F143 RF MCU, seems the company is rather miserly with its information, no training videos and no get started guide that goes past installing the IDE(s). Has anyone worked with these RF MCU's before?I must say they seem to have a decent library set but there is no information pertaining to the functions in those libraries nor how they can be used. I tried going into C:\Program Files (x86)\AXSEM\AxCodeBlocks to open and read through the source files but they just aren't there.Please help.
Getting started with Wemos D1 Mini Pro - Page 1
Forum section: electronics / projects

author: jtronix
author_rank: Regular Contributor
timestamp: March 26, 2017, 04:00:53 pm
content: Hi,I want to interface D1 mini pro module with my LPC1788 microcontroller.How do I program Wemos D1 mini pro??I want to use it for MQTT and HTTP??After searching many examples I found that most of the people are using Arduino, where they are using Arduino IDE. but I want to interface it with LPC1788can any one plz advice?

author: mbless
author_rank: Regular Contributor
timestamp: March 26, 2017, 07:10:04 pm
content: It looks like the other thread with my reply was deleted.Program the Wemos in Arduino and communicate with the MCU via I2C or SPI.

author: LukeW
author_rank: Frequent Contributor
timestamp: March 27, 2017, 02:12:21 am
content: Do you really need a ESP8266 plus a separate microcontroller? The ESP8266 is a pretty capable microcontroller for its price.

author: jtronix
author_rank: Regular Contributor
timestamp: March 27, 2017, 08:27:07 am
content: my application is little complex so i need seperate controller.ESP8266 has SPI and UART so i think i can use them and interface with LPC1788
Getting weird ground signals with thermocouple - Page 1
Forum section: electronics / projects

author: diegoterc3
author_rank: Regular Contributor
timestamp: February 18, 2015, 06:37:43 pm
content: Hello,I am trying to make a reflow oven and have already made my first prototype for testing.I can´t get my MAX6625 to read anything from the K type thermouple. I need help! On the datasheet it said that in order for the cold junction compensation to work the negative side of the thermocouple had to be connected to ground wich I did. When I meassure GND with an oscilloscope I get the negative thermocouple signal ofcourse. Will this make my MCU crazy?Also I have some questions about the thermocouple wave form. Is it supposed to be this way? (see image).Thank you!!

author: Andy Watson
author_rank: Super Contributor
timestamp: February 18, 2015, 06:58:45 pm
content: Quote from: diegoterc3 on February 18, 2015, 06:37:43 pmCannot read ?or can read but data is garbage?

author: diegoterc3
author_rank: Regular Contributor
timestamp: February 18, 2015, 07:02:59 pm
content: Cannot read. I am cheking my code as well and debugging everything line by line to check if everything is ok.

author: diegoterc3
author_rank: Regular Contributor
timestamp: February 19, 2015, 04:24:52 pm
content: All right I made it work. The thermocouple wasn't making any contact to provide the signal.But I would still like to know the answer. Would connecting the negative side of the thermocouple affect other digital devices because of the dynamic reference (GND)?Thank you!
GFSK deviation and baudrate - Page 1
Forum section: electronics / projects

author: qsdr
author_rank: Newbie
timestamp: April 23, 2014, 11:48:26 am
content: Hi,What is the relation between the frequency deviation and the baud rate in the GFSK modulation?

author: VK5RC
author_rank: Unknown
timestamp: April 23, 2014, 11:52:23 am
content: Doesn't the Hartley Shannon theory relate the two (frequency deviation equiv to channel bandwidth) directly along with the signal to noise ratio of the channel?PS One of the Agilent App Notes has a nice graph of some of the limits of digital comms along with signal to noise.http://cp.literature.agilent.com/litweb/pdf/5952-8255E.pdf

author: qsdr
author_rank: Newbie
timestamp: April 23, 2014, 03:47:21 pm
content: The Hartly Shannon theorem is fp <= 2BW, with BW is the band width and fp is the pulse frequency.But for the GFSK modulation I found the following theorem: BW = 2Fd + Rb, with Fd is the Frequency deviation and Rb the data rate. So what is the relation between this two rules?In other side, what is the rules to chose correctly the baud rate and the frequency deviation to have the best distance range.
Giant rotary switch teardown - Page 1
Forum section: electronics / projects

author: Mysion
author_rank: Regular Contributor
timestamp: November 16, 2016, 01:25:47 am
content: The unboxingI ordered a 10 position switch for a project expecting a normal sized switch. I did not check the scale the item and ended up with this beast! I was trying to figure out what the box was for and and ended up with a switch that fill my hand. It's got some weight to it too.My initial impression is that it's used but still in great shape. The action is REALLY satisfying, it's got a good cur chunk to it.Rear of switchFrom the number of wires I'm guessing it's a 2 pole switch. The wires are still in good shape and it looks clean here too. The screws holding on the rear mounting bar were in threaded inserts surprisingly enough.With front dial removedThe front dial was held on my a large flat head screw and indexed onto the shaft with the rod seen here.The reason for the satisfying feel is now apparent. The spring pushes the ball against the grove in the front dial. For a simple system it works really well.Inside of the switchNow that we are in we can see the REALLY beefy contacts in side. The huge copper leafs are angled on the contacts to get the most contact area. They are doubled up as well. There's a second leaf under each of the ones you can see here.Even after all these years it still moves smoothly. I imagine this thing can handle tons of current.The screws holding the case together used threaded inserts same the the back. They really spared no expense. I would love to know who made it and how much it cost but I can't even recognize the logo.10/10 Best impulse purchase ever. It was only ~16$ after shipping too!TLDR: I love big knobs and I can not lie.Any one have any idea who made this? Or where to find more?Full Size Album

author: edavid
author_rank: Super Contributor
timestamp: November 16, 2016, 01:29:39 am
content: Leeds & Northrup

author: Vgkid
author_rank: Super Contributor
timestamp: November 16, 2016, 04:16:11 am
content: I was looking at that one on fleabay. That is an older one, as they switched to silver contacts, then to the type 31.

author: Mysion
author_rank: Regular Contributor
timestamp: November 16, 2016, 01:51:09 pm
content: edavidThanks for the name! Going on ebay it looks like they made high end test equipment! I might have to pick one of those items up some time.Alex EisenhutThat about sums up my reaction when I took it out of the box. I was expecting a normal sized switch not this giant beast!VgkidDo you know what time period or is there a way to find out? Would the 30's - 40's be a good guess based on your experience?Any recommendations on maintenance. Do I need to oil the contact or clean them or should it be good to go?

author: calexanian
author_rank: Super Contributor
timestamp: November 17, 2016, 04:30:36 am
content: I can feel the quality through the screen. Good stress relief spinning that thing all day.
Gigabit ethernet ESD protection - Page 1
Forum section: electronics / projects

author: gaminn
author_rank: Frequent Contributor
timestamp: January 26, 2020, 06:23:44 pm
content: Hi,I would like to createESD protection for my home gigabit switch and gigabit IP cameras (small box with input RJ45 connector, ESD diodes, output RJ45 connector and grounding wire). There is 48V PoE involved (either passive or IEEE 802.3af).I found some low capacitance esd chips, e.g.http://www.ti.com/lit/ds/symlink/esds314.pdf. These ICs are referenced to ground to protect protected device from surge voltage between twisted pairs. If I understand that correctly, this would mean a problem for PoE - the diodes in ESD chip would short PoE voltage.How is ESD protection done when PoE is involved? Can I solve the problem by not connecting ESD chip to ground directly but via +- 50V ESD diode?

author: David Hess
author_rank: Super Contributor
timestamp: January 28, 2020, 02:32:40 am
content: I have one I could take apart but the general solution is to use GDTs (gas discharge tubes) on the exterior interface from each signal to ground and they have a breakdown voltage greater than any PoE standard.
Gigabit Ethernet Phy Unused interface - Page 1
Forum section: electronics / projects

author: electronx
author_rank: Regular Contributor
timestamp: March 04, 2025, 10:13:43 am
content: Hello everyone,I am working with the MXL86111I-AQB-R GBE Ethernet PHY and using RGMII instead of SGMII. Since the SGMII interface is not used, I am unsure how to properly handle the related pins:Pin 38 (RX0_P) – SGMII Data Input (Positive)Pin 39 (RX0_M) – SGMII Data Input (Negative)Pin 40 (TX0_P) – SGMII Data Output (Positive)Pin 41 (TX0_M) – SGMII Data Output (Negative)From my understanding:RX0_P and RX0_M (Input pins) → Should they be left floating or pulled down with resistors?TX0_P and TX0_M (Output pins) → Is it safe to leave them unconnected (NC), or do they need termination?I checked the datasheet, but I couldn’t find a definitive recommendation for unused SGMII pins. Any insights or reference designs would be greatly appreciated!Thanks in advance!

author: fchk
author_rank: Frequent Contributor
timestamp: March 04, 2025, 07:06:59 pm
content: The easiest and cheapest way would be swapping the PHY for an MXL86110I-AQB-R. Same function, fewer pins (QFN40 instead of QFN48), cheaper, and without SGMII interface. No worries about unused pins.
Gigabit Ethernet Without Magnetics? - Page 1
Forum section: electronics / projects

author: gudenau
author_rank: Regular Contributor
timestamp: April 11, 2017, 02:28:11 am
content: I'm looking into making a backplane for a cluster computer made out of single board computers. Unfortunately the boards I'm targeting don't have Ethernet ports built in so I'm planning on incorporating USB-Ethernet chips for each node. From what I'm finding there is a standard for this "1000BASE-KX" but I can not find any chips that advertise support for this. What is the best way to Implement this for gigabit speeds over a PCB?

author: helius
author_rank: Super Contributor
timestamp: April 11, 2017, 02:44:26 am
content: You might want to look into Interlaken if you are exclusively over the backplane

author: David Hess
author_rank: Super Contributor
timestamp: April 11, 2017, 03:39:01 am
content: I think Microchip has an application note showing how to do this with 10/100 ethernet but the same principle applies to gigabit ethernet. What I remember is replacing the transformers with AC coupling capacitors and routing a differential transmission line.

author: gudenau
author_rank: Regular Contributor
timestamp: April 11, 2017, 03:47:22 am
content: Quote from: helius on April 11, 2017, 02:44:26 amThanks, I'll look into that.Edit:That looks almost like it is not the best idea in this case, I still need to have an outside link with the gigabit Ethernet that can talk to each node.Quote from: David Hess on April 11, 2017, 03:39:01 amI was worried they would disable gigabit because I know that ulyou can do that if you use a cap a certain way in a cable. I did find that note.
GIGATRON gets APOLLO program style CONSOLE - Page 1
Forum section: electronics / projects

author: RJSV
author_rank: Super Contributor
timestamp: June 26, 2021, 09:05:59 pm
content: Hello, The GIGATRON bug has bit (yet another) bored EE!Please see PICT, a crude first diagram.The CONSOLE bench places the GIGATRON wood box as the featured item. You can see placement of a soldering station, by the big arrow, to left of actual Gigatron box. The box, I prefer, has brackets to allowoperating up higher, with maybe an Artuino set-up underneath.The 'console' helps by simply providing a work surface, that might largely be maintained cluttered, if user focus on (whatever) project. Of course the inside portion can have your USB power wart etc.Actually this project idea started with speculation, onthe fine art of woodworking, planning for various upgrades in the wood and appearance. So it's 'ART', directly, but to give the user even more PRIDE in their work (on the Gigatron functions).Notice up top, I have a couple of VINTAGE meter movements, as you can see one of them placed in console.I TRIED TO GET AS MUCH OF A FEEL, OF AN APOLLOGROUND CONTROL CONSOLE. (For a vintage look).Also included: A couple solderless bread-boards,Some various un-assigned banana jacks and screw terminal blocks. Plus, you can see the vintage speaker box, on the floor to the left of the table-like console.(Of course there will also be some various AUDIO jacks for facilitating a speaker.)The whole thing is just a cute pile of wish-list technician stuff. Mainly, I wish to do the WOODWORK up really nice!What a great market situation, (if we can expand it, to practical scale, for users and venders alike!
Giovanni - Page 1
Forum section: electronics / projects

author: francesco_97
author_rank: Contributor
timestamp: June 01, 2022, 09:46:41 pm
content: Modern times require modern solutions. Do you feel angry because your brand new Tektronix scope has fucking readout rings and the only probe that you have is the switchable Rigol probe? Do you hate Tektronix because they didn't add a selectable probe multiplicator switch thinking that you'll spend 300 euros for a single probe while you are at university without any money income except for Christmas gifts?Well, Giovanni is here for you.Giovanni costs 20 cents. and it's made with a pipe filler (1 cm internal diameter, 1.8mm thickness) and a 10k resistor bent to reach the back and the internal circle of the filler. Giovanni lets you read the right values from your scope without any internal hack or goofy springs. Forget to use your brain to do a simple 10x multiplication. The rubber prevents scratches on the readout rings, providing insulation with the BNC connector and a natural spring action while the resistor wires do the trick. A new level of fitness lets to insert Giovanni between your scope and any probe in the universe. Don't let Tektronix ruin your day, use Giovanni. Tests (?!?!?!) with a Tektronix p6112 fixed 10xand with a switchable Rigol pvp3150.The future is here.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: June 02, 2022, 09:12:14 pm
content: Modern? That scope is almost 40 years old!

author: francesco_97
author_rank: Contributor
timestamp: June 02, 2022, 09:28:41 pm
content: You are right, this scope is only 40 years old, it's TOO MODERN. I don't think that the world is ready for the crt monochrome display and the leds on the front panel.

author: bob91343
author_rank: Super Contributor
timestamp: June 03, 2022, 01:58:33 am
content: What's a pipe filler and where do I get one? Or six?

author: quadtech
author_rank: Regular Contributor
timestamp: June 03, 2022, 05:01:51 am
content: Nice work - Grazie, Giovanni.Quote

author: francesco_97
author_rank: Contributor
timestamp: June 03, 2022, 08:04:10 am
content: Absolutly right. Sorry but i translated directly, the right name is faucet washer but as you said any rubber ring is good. I founded them in a local hardware store, just remember to use 1.0 mm tip to drill holes. Ah and remember, Giovanni is the name of the adapter, not mine.
Github Desktop not showing any file changes ONLY when made with Eclipse editor - Page 1
Forum section: electronics / projects

author: ricko_uk
author_rank: Super Contributor
timestamp: August 08, 2024, 01:04:15 am
content: Hi,I have lost track of how many hours I have spent trying to figure this out, reading forums and documentation... so any help is much appreciated!I installed GitHub Desktop and created a local repository which resides inside a sn STM32 CubeIDE project... i.e. Eclipse.I can modify any of the .c or .h files with ANY editor (notepad, notepad++, wordpad, etc) and the changes appear immediately in GitHub Desktop. But if I edit the same file/s with CubeIDE editor the changes do not appear, at all. i.e. GitHub Desktop does not show that the file (or any file) has been changes.Does anybody have any idea why?Thank you as always!

author: bson
author_rank: Unknown
timestamp: August 09, 2024, 08:15:06 pm
content: Did you save them? Note also that Eclipse has git integration and can be set to automatically 'git add' any changes to tracked files. You can then diff, commit, push, pull, merge branches etc through Eclipse.

author: ricko_uk
author_rank: Super Contributor
timestamp: August 09, 2024, 11:25:02 pm
content: Thank you @bson,yes that was the first thing I made sure of.It works with every other Git client (SourceTree, Git Kraken etc) but not specifically with Git Desktop.
Give me a good Led driver switcher IC - Page 1
Forum section: electronics / projects

author: LM21
author_rank: Regular Contributor
timestamp: November 27, 2023, 03:46:38 pm
content: I want to build a LED driver for 1 or more White Leds (can it be less than1). Led current should be less than 20mA, input voltage one or more LI-ion battery. PWM or not. Either hand solderable or something JLCPCB can assemble.I can use higher current driver, but requires different LEDs.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: November 27, 2023, 07:56:02 pm
content: I think I like the PT4115. It's one of those ali specials that cost next to nothing. I think bought 50 for EUR2, then wanted to put them in a drawer and then laid them next to those other 50 I bought a year earlier (Sigh).But I have tested a few and they do work. They are current mode step down with adjustable current switching threshold (adjustable with a shunt resistor). They switch up to 1A and input voltage can be up to 30V or so.

author: LM21
author_rank: Regular Contributor
timestamp: November 27, 2023, 11:16:07 pm
content: "I think bought 50 for EUR2, then wanted to put them in a drawer and then laid them next to those other 50 I bought a year earlier (Sigh)." I fully understand. I could not find it later, but when I bought a second one, and put it away for a while I found the first one there too.

author: langwadt
author_rank: Super Contributor
timestamp: November 27, 2023, 11:29:27 pm
content: if you want to do both one or more LEDs and one or more LI-ion batteries, you'll need both buck and boost, don't think there's too many of those

author: LM21
author_rank: Regular Contributor
timestamp: November 28, 2023, 01:59:31 pm
content: I think boost is best for me here. I'd like to have several white LEDs and I can live with the fact that battery voltage must be lower than the LED voltage.

author: PSR B1257
author_rank: Frequent Contributor
timestamp: November 29, 2023, 01:30:43 pm
content: Choose your poisonhttps://www.analog.com/en/parametricsearch/11276#/

author: newbrain
author_rank: Super Contributor
timestamp: November 29, 2023, 03:10:30 pm
content: This driver might be what you're after, depending on the kind of control you need and the actual number of LEDs.NXP PCA9955BI'm going to use it as a PIN diode driver to select RF bandpass filters.It is hand solderable with just a soldering iron, if you put a (possibily oval) PTH under the GND exposed pad.
Giving a talk to grade 9 students (Looking for Demo Ideas) - Page 1
Forum section: electronics / projects

author: devinatkin
author_rank: Contributor
timestamp: March 09, 2022, 03:27:31 pm
content: So a local online school teacher wants me to come talk to her classes about electrical engineering. It's going to be ~200 students across all the classes which are attending. I'm looking for ideas of demonstrations that will entertain and engage a bunch of 9th graders which translate well to video call demonstrations.Ideas would be appreciated. I have a few thoughts so far, but I need to make sure I fill the 45 minute class time so more demos or cooler demos would be appreciated.

author: CaptDon
author_rank: Super Contributor
timestamp: March 09, 2022, 03:42:20 pm
content: A big d.c. permanent magnet type motor would be cool, connect a bipolar red/green led to the output (with resistor of course) and turn it one way the red led lights, turn it the other way the green led lights. Put a shorting switch across the motor and allow one of the students to turn the shaft with and without the short to demonstrate regenerative braking. Get a pair of selsyn syncro motors with an a.c. power supply and about 10 feet of wiring. Have two students turning the shafts with no power applied, then have the students feel the resistance or motion induced by each other when the power is turned on. I did exactly these things for a journeyman electrician course. The students really liked the hands-on demo.

author: mcsoftware
author_rank: Contributor
timestamp: March 09, 2022, 05:10:01 pm
content: How about a Slayer Exciter Tesla CoilHere's some of my posts on the subject:https://www.eevblog.com/forum/projects/my-two-tower-slayer-exciter-tesla-coil-(two-towers-better-than-one)/https://www.eevblog.com/forum/projects/i-finally-got-my-homemade-tesla-coil-(slayer-exciter)-working!/https://www.eevblog.com/forum/projects/my-mini-tesla-coil-video-(also-transistor-switchingchecking-nostalgia-etc-)/

author: jonpaul
author_rank: Super Contributor
timestamp: March 09, 2022, 05:56:17 pm
content: Suggest the $50 ready built mini Tesla Coil on ebay from China, small and safe but nice for demos...Jon

author: TimFox
author_rank: Super Contributor
timestamp: March 09, 2022, 06:55:31 pm
content: Can you outfit a bicycle with a generator and have a volunteer from the audience power a set of light bulbs?

author: devinatkin
author_rank: Contributor
timestamp: March 10, 2022, 03:24:47 pm
content: This time it won't work so well cause it has to be over zoom. But next time I get to do an in-person thing to students like that I'm totally doing that. It's a great idea.

author: devinatkin
author_rank: Contributor
timestamp: March 10, 2022, 03:27:48 pm
content: Quote from: TimFox on March 09, 2022, 06:55:31 pmThat would be great unfortunately I have to do it remotely.

author: Terry Bites
author_rank: Super Contributor
timestamp: March 10, 2022, 04:15:30 pm
content: A treadmill full of rats? Waterwheel? Wind from a fan?
Giz a look at yer work bench mate - Page 1
Forum section: electronics / projects

author: ANTALIFE
author_rank: Frequent Contributor
timestamp: February 23, 2016, 08:17:38 am
content: Though I'd share my kinda electronics project, a better workbench.Bought a table at IKEA but even with all the storage boxes it became quite messy. Later I got an old school Tektronix scope and though might as well build a bench around it. A month and a half later voila, am finally ready to vertically clutter up my desk.With all that said, what do your fellas work benches looks like?

author: kripton2035
author_rank: Super Contributor
timestamp: February 23, 2016, 08:26:57 am
content: nice space optimisation !but you cannot put another storage box in it, and you always need more storage boxes as projets goes by ...what kind of wood did you use ?

author: ANTALIFE
author_rank: Frequent Contributor
timestamp: February 23, 2016, 08:35:44 am
content: Quote from: kripton2035 on February 23, 2016, 08:26:57 amCheers, yea each space was designed around the storage boxes I have on hand (not in picture). And yup you are right, the point of needing a bigger work bench is inevitable as time passesThe framing is made out of Standard Grade Dressed Pine (42mm x 19mm) while the shelves are out of AA Grade Mixed Hardwood (9mm thick).
GL823 sd card reader, no response - Page 1
Forum section: electronics / projects

author: martin321
author_rank: Newbie
timestamp: November 28, 2015, 04:50:40 pm
content: Hi,I am trying to get the GL823 card reader to work, but there is no response from the pcb when I plug in the USB cable.There is 3.3v DVDD, 1.5v on LED pin and nothing on PMOS or AVDD.No resistors placed at R1 to R5.Received the design guide and datasheet from supplier. Think I have correctly copied it.gl823_sch.pdf is the one I have made.If anyone could help me out I would relay appreciate it.Martin

author: martin321
author_rank: Newbie
timestamp: December 07, 2015, 06:52:38 am
content: Found the post linked under. Anyone that can see my error?https://www.eevblog.com/forum/beginners/issues-with-breadboard-sd-card-reader/

author: mich41
author_rank: Regular Contributor
timestamp: December 08, 2015, 01:37:04 pm
content: QuoteHint: where the power to AVDD is supposed to come from?

author: martin321
author_rank: Newbie
timestamp: December 08, 2015, 04:21:09 pm
content: Sorry, but I don't follow you.

author: wraper
author_rank: Unknown
timestamp: December 08, 2015, 04:32:58 pm
content: Quote from: martin321 on December 08, 2015, 04:21:09 pmDo you expect AVDD to appear from nowhere? It is externally connected to the chip. On the gl823_sch.pdf through the L1 inductor from the DVDD.

author: mich41
author_rank: Regular Contributor
timestamp: December 08, 2015, 04:59:40 pm
content: Well, DVDD does appear out of nowhere, so go figureSeriously though, page 16 of the datasheet kinda suggests that the internal 3.3V regulator outputs to DVDD and then note1 on page 12 tells that AVDD needs to be hooked up to that through a bead.
GLASS voltage divider resistor very special find - Page 1
Forum section: electronics / projects

author: oz2cpu
author_rank: Frequent Contributor
timestamp: December 19, 2024, 07:05:40 pm
content: normally you see those caddock cheramic resistors in all sorts of equipment,I just wanted to share with you this cool open glass version, see that attached pictures,I also released a little video about the voltmeterData Precision model 1450where i found this really nice component, have any one seen this one before ?https://youtu.be/IhpYi3eyX_k

author: Benta
author_rank: Super Contributor
timestamp: December 19, 2024, 10:11:58 pm
content: Extremely cool!Almost as nice as the SAW filters posted some time ago.
Glitch generator - Page 1
Forum section: electronics / projects

author: Chupacabras
author_rank: Regular Contributor
timestamp: September 11, 2015, 04:08:34 pm
content: What is used as "glitch generator" in this video?https://youtu.be/uDBuUI5GZ7Q?t=2020I know that it was used several times in some previous videos.Is it some professional tool, or homebrew one?How to build one? I am not able to find any scheme

author: Stupid Beard
author_rank: Regular Contributor
timestamp: September 11, 2015, 04:24:56 pm
content: I think it's coming from his Agilent scope. It has a training mode that will generate a bunch of different signals to teach you how to trigger on them.

author: Chupacabras
author_rank: Regular Contributor
timestamp: September 12, 2015, 07:46:52 am
content: I think you are right. Dave mentioned it in some video years ago (I think).Anyway, could anyone give some advice how to build similar glitch generator?

author: RogerRowland
author_rank: Regular Contributor
timestamp: September 12, 2015, 08:09:13 am
content: Quote from: Chupacabras on September 12, 2015, 07:46:52 amMost of the stuff I build comes with glitches as standard!

author: Chupacabras
author_rank: Regular Contributor
timestamp: September 12, 2015, 08:25:37 am
content: Well, I am looking for glitch-free glitch generator, if you know what I mean

author: Howardlong
author_rank: Super Contributor
timestamp: September 12, 2015, 08:46:08 am
content: I made one with a PIC24F Microstick (http://www.microchip.com/DevelopmentTools/ProductDetails.aspx?PartNO=DM240013-2) a couple of months ago. This includes a PIC with a pair of DACs. The board has an integrated programmer/debugger, so all you need is the board itself hardware-wise.I did code for random glitch generation, random runt pulses, AM modulation, and AM modulation with glitches. I didn't get around to adding I2C/SPI/UART.If there's any interest I'll tidy the code up, add the serial generators and publish it.

author: Chupacabras
author_rank: Regular Contributor
timestamp: September 12, 2015, 08:57:00 am
content: Yeah, sure I am interested to see your codeI have Pickit3 programmer/debugger, so I could build my own board.I am learning, so this little project could be good for me.
Glow-in-the-dark pot? - Page 1
Forum section: electronics / projects

author: calzap
author_rank: Frequent Contributor
timestamp: May 12, 2013, 02:27:30 pm
content: So, I'm looking for a 3-5 W, 15 K pot, and stumble across a listing on Amazon for a 500 W, 2.2 K wire-wound pot. URL =http://www.amazon.com/Amico-Resistance-Electrical-Wirewound-Potentiometer/dp/B0087YJ3IQ.I think it has to be as big as a toaster. Nope, 4.3 cm diameter, 4 cm height, and 1/2 the height is shaft. If my calculations are correct, the "can" has a surface area of 56 sq cm, so that's 9 watts per sq cm. Should get a little hot in most environments. Maybe the spec is off by a couple of decimal places?Mike in California

author: Dave
author_rank: Super Contributor
timestamp: May 12, 2013, 02:45:50 pm
content: I foundthis.3W at 55°C, zero at 100°CThe person that wrote that Amazon ad obviously screwed up.

author: c4757p
author_rank: Super Contributor
timestamp: May 12, 2013, 02:52:04 pm
content: Yep. And 500W into 2k2 is 1kV! Even at 10% of the range you'd need 330V. You will know when you're looking at a pot that can stand off 1kV...

author: KD0CAC John
author_rank: Frequent Contributor
timestamp: May 12, 2013, 03:06:12 pm
content: I thought I remembered glowing in the dark after pot .Oh sorry , wrong prospective
Glue - Page 1
Forum section: electronics / projects

author: rakeshm55
author_rank: Regular Contributor
timestamp: July 25, 2013, 02:09:03 am
content: What is the type of glue used in the image??

author: Jebnor
author_rank: Regular Contributor
timestamp: July 25, 2013, 02:19:25 am
content: White.

author: robrenz
author_rank: Super Contributor
timestamp: July 25, 2013, 02:30:27 am
content: Probablyneutral curesilicone

author: rakeshm55
author_rank: Regular Contributor
timestamp: July 25, 2013, 03:31:28 am
content: I have usually used Hot glue gun + glue stick to bound electronic parts. But i guess it has a limited temperature range and I am not sure about the long term performance of such technique . I have seen the adhesive ripped off with a feather touch, once exposed to sunlight for a long time (4hrs).I would like to know the s bounding techniques/ potting techniques and items available in market especially for industrial environment and military environment.

author: Berni
author_rank: Super Contributor
timestamp: July 25, 2013, 06:38:28 am
content: That's silicone alright, it works well but hot glue is much more convenient.To protect thing from the environment I normally use wood lacquer. It hardens in to a nice waterproof coat in about a day.
GM LSx ECU ign output cct - Page 1
Forum section: electronics / projects

author: Circlotron
author_rank: Super Contributor
timestamp: November 28, 2019, 03:15:29 am
content: Hi. What I am looking for is a partial schematic of a GM LS and newer ECU that shows the circuitry inside the ECU that drives the ignition coils. Specifically the little transistor and maybe collector pullup resistor and whatever else that gives the 0-5V output signal to the wiring loom that goes off to the ignition coils. I want to build an ECU simulator that gives the exact output that a real ECU would, as far as voltage levels and drive capability is concerned. Just simply using a sig gen is not what I want.

author: floobydust
author_rank: Super Contributor
timestamp: November 29, 2019, 02:27:44 am
content: You'd have to narrow down the model of GM ECU and mated ignition coil modules.ECU ignition driver outputs are generally push-pull 5V current-limited to 20mA, with protection so a short to +12V will not backfeed and raise the ECU 5V rail, destroying it.The ign module typically has a smart coil-driver IC and IGBT inside.Some models of ECU and coil, the ignition coil module can (over the 5V trigger wire) send back diagnostic info to the ECU, such as current-limit target reached, over-dwell timeout.The ECU can also look for its (trigger) output shorted to GND or shorted to +12V battery, or open load.So the trigger line is not only a digital output but also can have switched current-sinks (by the coil module) on it, for diagnostics.If you want to fully test ignition coil modules, it's not just the spark but also the diagnostic signals to consider.
GM120041 (LT1963 clone?) - Page 1
Forum section: electronics / projects

author: Paroidia
author_rank: Contributor
timestamp: February 13, 2024, 10:34:03 pm
content: So I need a very low dropout LDO for a servo breakout PCB intended to power servos off a 7.4v or less battery (7.4v lipo / li-ion or 6V NiMH depending on whether standard servos or HV servos are connected) while providing direct battery power to the servos and 5v to a multirotor flight controller that is providing the servo control signals (PWM throttle signals are the same thing as PWM servo position control signals) and possibly a 5V receiver. I've been using a TPS76801 for this but it's annoying to order things with that chip from JLCPCB because they don't normally have it in stock and I have to pre order it to my parts library.The switching regulator on an FC will typically start having trouble below 6V which is why I power it with a 5V LDO connected to the 5V rail on the FC.I found this on LCSC,https://www.lcsc.com/product-detail/Linear-Voltage-Regulators-LDO_GONGMOSEMI-GM12041ARDZ-R7_C7463178.htmlThis is cheaper than the TPS76801 I've been using and JLCPCB has it in stock regularly Pinout is the same as an Analog devices LT1963 except the dropout voltage stated by the datasheet is much lower. Even if they are fudging I could derate it to 1A and still get about the same dropout assuming the dropout is similar to the analog devices chip.Anyone heard any bad things about this company's stuff?(attached circuit and PCB, pretty much just dropped the new regulator into the existing design and reworked the PCB a little)EDIT in case anyone is wondering what D1 is for it's because the FC is plugged into USB to configure it which also powers the 5V rail
GND routing for PCB strategy - Page 1
Forum section: electronics / projects

author: john23
author_rank: Frequent Contributor
timestamp: November 18, 2024, 06:34:35 pm
content: Hello , I have made the PCB of my sequencer, I need to connect the GND's nets together .They are varius.I can do polygon pour , I can do direct track routing.How do you reccomenf to connect the GND in this circuit?PCB and video are attached in the link below.Thanks.https://www.minicircuits.com/pcb/WTB-PMA5-83-2WC+_P02.pdfPMA5-83-2W+.pdfhttps://drive.google.com/file/d/1mxI4-UuYSeHTCj1M244HBF1TjQS3t8lG/view?usp=sharing

author: tooki
author_rank: Super Contributor
timestamp: November 18, 2024, 11:48:38 pm
content: Please just share a PDF of the schematic.

author: Andy Chee
author_rank: Super Contributor
timestamp: November 19, 2024, 12:10:43 am
content: Ground planes on both red & blue layers, with both layers stitched together with vias.

author: john23
author_rank: Frequent Contributor
timestamp: November 19, 2024, 01:39:52 pm
content: Hello tooki,schematics is attached.if you have some more tips it would be great.

author: Randy222
author_rank: Frequent Contributor
timestamp: November 19, 2024, 02:39:19 pm
content: Pours are common, then via stitch them accordingly.

author: bson
author_rank: Unknown
timestamp: November 20, 2024, 06:23:21 pm
content: D1 connects M12 to ground with a Schottky diode. Is this what you meant to do? That's going to practically short out M12. Or did you mean to clamp it with a zener?
GNT library for Virtuoso - Page 1
Forum section: electronics / projects

author: promach
author_rank: Frequent Contributor
timestamp: June 29, 2020, 04:27:52 pm
content: I am trying to usehttps://web.archive.org/web/20180923235322/http://www.analogdesign.be/general-network-theorem/gnt-integration-in-virtuoso/gnt-library, buthttps://bitbucket.org/analogdesign/gnt/issues?page=3does not have any source files.Could anyone help ?
Going to generic Arduino with LT2983 - Page 1
Forum section: electronics / projects

author: gilbenl
author_rank: Regular Contributor
timestamp: March 09, 2016, 06:57:44 pm
content: I've been working on a project to build an in vivo temperature acquisition system for biomed research. I recently got ahold of some LT2983s to provide an all-in-one solution. Unfortunately, I can't seem to get the thing to work with a standard arduino. The "Going Generic" article doesn't seem to apply to this particular chip.Here's the referenced article:http://www.linear.com/solutions/4537I've dug through the corresponding .h and .cpp files, but despite a few attempts, can't get it to work on either Arduino Uno or Nano (both fakes but worked with LT1867). Of note, when I upload the any of the demo .ino, I get "2983" in the serial monitor indicating the SPI bus was initiated, but nothing further. When I disconnect the SPI-MISO line, I get line after line of output dialog showing errors, which originates from the Arduino, not the 2983.Need a bit of spoon-feeding on this one as this is my first foray into SPI. Thanks in advance. Happy to answer any additional questions or provide images etc.

author: quantumvolt
author_rank: Frequent Contributor
timestamp: March 10, 2016, 02:41:49 am
content: First, I would send a PM to this guyhttps://www.eevblog.com/forum/microcontrollers/linduino-smart-isolated-arduino-compatible-board-for-daq-demo-boards-etc/msg858580/#msg858580. I think he said somewhere that he got it to run.Secondly, put in debug writes in the LT code from the very beginning to where you expect data from the chip. There is probably nothing wrong with the chip or the code. But even if SPI / I2C is just a few hex'es and a select / address, it is often a lot of work to initialize the chip and get the first data transfer running.You may find it easier to strip down the somewhat bloated LT code to a bare minimum for recognizing the board / chip, selecting the bus / chip and send / retrieve a single data packet.Go through it all systematically and it will surely work ...
Gold detector (Pointer) - Page 1
Forum section: electronics / projects

author: Ugur
author_rank: Regular Contributor
timestamp: February 13, 2024, 07:51:01 am
content: Hello, I want to make a gold detector (pointer). Do you have a circuit diagram that you are sure works?

author: Ian.M
author_rank: Super Contributor
timestamp: February 13, 2024, 08:38:41 am
content: No. Non-ferrous metal detector circuits have short range and don't discriminate effectively between gold, and the likes of lead shot from hunters or aluminium can pull rings. They are of some use for prospecting alluvial gold deposits, but no substitute for lots of digging.XRF spectrometers are extremely complex and far outside the capabilities of virtually all hobbyists to build. Although they can detect gold (and distinguish between elements detected) they cant do so remotely so are ineffective if the target is concealed by even a few cm of dirt or separated by a few tens of cm of air.Anything that claims to help you find gold by pointing towards it is a form ofdowsing, a debunked psuedoscience. It only finds gold for the scammer that convinces you to buy it, and that gold is coming straight out of your bank account!

author: Ugur
author_rank: Regular Contributor
timestamp: February 13, 2024, 11:03:02 am
content: Hello Ian.You are right.Only those who sell these devices make money in the gold search business.Thank you for the information you provided.