hybridfree/eevblog-posts huggingface dataset:
I build a multiroom a/c by using a standard movable a/c - Page 1
Forum section: electronics / projects

author: athtrya
author_rank: Newbie
timestamp: June 19, 2019, 04:01:24 pm
content: So I build a multiroom a/c by using air duct and authorized air valve.It's actually the Rev 3 of this projectSo how it's work:for each room there are a standard thermostathttps://ln.sync.com/dl/15be9e730/3t5ux7j7-qk8x78z4-87psrtkf-xj83jbbt/view/default/2870112860010that are able to ask for heat, cold or only fan (the fan is on each mode with 3 speed) [actually I have a problem on this part because all the thermostat are independent so all can send all the output it there are no priority, I know basically the method to resolve this problem but I don't able to do it, basically it's to resolve this problem by using a microcontroller, in the old way by using only electronic components by different gate, or in the complicated way by modifying the app for the thermostat or directly the program inside the thermostat. But sadly even if I have the material to do it I'm not competent to any of this solutions.]The continuation of the system:When the thermostat is on heat mode this activate the compressor, inverter, fan, air valve for of the room there the thermostat ask forWhen the thermostat is on cool mode this activate the compressor, fan, air valve for of the room there the thermostat ask forWhen the thermostat is on fan mode this activate the fan, air valve for of the room there the thermostat ask forThe air go to the room by two possible way or new air, or recycled air, in any case the air go to a filter, and to the a/c even only in fan mode, the enter way for air is choose by the the temperature difference between the inside air and the outside air (on the principle anyway)Here is the actual diagram of the air systemhttps://cp.sync.com/dl/5caa1df50/ht57c8rr-pth2tqcm-atp3gcqa-8qqk4mfthttps://cp.sync.com/dl/ef222a850/cj8wafb9-fnrkreiw-8d7pt2jf-agajhcbs
I built a GSM/GPS shield for the Teensy 3.1/3.2 with CAN Bus - Page 1
Forum section: electronics / projects

author: Fid
author_rank: Contributor
timestamp: February 19, 2016, 05:52:55 am
content: Hey guys,Just wanted to share my little project with you. It has been a year in the making and a huge learning experience.I have been using the Teensy for a couple years after I started with an Uno and soon realized it wasn't capable of doing all the things I had in mind. The Teensy did everything, but I always thought it would be great if I could make it mobile. There were GSM shields available back then, but they were mostly huge, meant for the Uno and Mega boards.So I designed this board that has the same footprint as the Teensy and packs in some nice features. I was working on a car CAN project at the same time so I thought I'd add that to the board and allow both boards to be powered by around 12V. There's a lot of I/Os still available on the Teensy to accompany all kinds of sensors for input data that can then be sent to the cloud.This was one of the first prototypes with a couple bodge wires and a lot of testing to be done.And here's the final version all finished and working.You can find more info and specs atwww.tinytracker.ioif interested.Let me know what you think!

author: RobertBG
author_rank: Regular Contributor
timestamp: February 19, 2016, 09:49:43 pm
content: Nice work,I started to build something similar a while ago for teensy with the Sim800L but ended up jumping ship.I got it working but never to the level I had hoped,mainly because I needed everything to work with a HID reader.I had started with a serial reader that was given to me but just about had a heart attack when I realized the price difference at a later time and just shelved everything.
i call it the ultimate power supply - Page 1
Forum section: electronics / projects

author: Eslam
author_rank: Newbie
timestamp: July 13, 2018, 10:12:53 pm
content: hello guysmy name is eslam and i've done a small project i call it the ultimate power supplymy power supply has an arduino avr328 chip inside to control the whole thingand i control the variable voltage and current through dc-dc converterthe main power source is 2 18v 3amps connected in parallelfeaturesmax current limit cut offmin drop voltage cut offbattery chargerbuzzer alarmdot matrix 1602 screenit's an open source project and i think some people here maybe interested to improve ithere is the project video including the schematic and the PCB

author: Ysjoelfir
author_rank: Frequent Contributor
timestamp: July 13, 2018, 11:31:01 pm
content: Since I don't have the best network connection right now I would be happy if you could share the schematic and layout in an universal form like PDF as I can't take a look at the video. Thanks!

author: Eslam
author_rank: Newbie
timestamp: July 14, 2018, 04:42:04 am
content: surehere is the link to schematic and boardhttps://drive.google.com/drive/folders/13B2LDXFtgfuueqFDiM3VOX6_jLHPJZoM?usp=sharingand i will export pdf in same folder today

author: Eslam
author_rank: Newbie
timestamp: July 14, 2018, 06:21:32 pm
content: check out the pdf schematic and gerber files guysi attached them herehttps://drive.google.com/drive/folders/13B2LDXFtgfuueqFDiM3VOX6_jLHPJZoM?usp=sharing

author: Mechatrommer
author_rank: Super Contributor
timestamp: July 14, 2018, 08:15:56 pm
content: what type of dc-dc converter you use and how you control V and I to it?

author: Eslam
author_rank: Newbie
timestamp: July 15, 2018, 09:46:13 pm
content: you can choose any stepdown dc-dc converter with adjustable currentdon't forget to choose in range of your own power supply and just edit the max limit in code

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 15, 2018, 10:59:06 pm
content: Yikes, that's the biggest, ugliest, messiest, most unreadable schematic I've ever seen. I can't make heads ortails of it. It looks like something a genetic algorithm evolved, yet (mostly?) manages to avoid basic electrical errors? I don't even know how this is made... I'm impressed.Tim

author: Mechatrommer
author_rank: Super Contributor
timestamp: July 15, 2018, 11:13:56 pm
content: What i know is the fan's transistor is running in linear mode. According to him current is controlled in dcdc module not shown hence i dont know what the opamps are doing down there sensing low side (i guess) shunt and outputs connecting each other. And there are unknown /redundant? Inductors everywhere which is a cryptic mystery...
I came up with this temp controlled fan circuit. - Page 1
Forum section: electronics / projects

author: Refrigerator
author_rank: Super Contributor
timestamp: June 11, 2015, 04:14:25 pm
content: So i was out of thermistors but i needed something to turn on a fan when temperature's too hot so i quickly came up with this simple circuit which uses a diode to sense the temperature:http://gyazo.com/d664fff48508359a40c04e13479ac83eThe circuit was tested on a breadboard and can be adjusted to work with any silicon diode using the 5k pot which also adjusts at what temperature the fan turns on.The fan does ramp up quite quickly when giving it a brief blow of hot air ( set to 100oC @ ~10cm using 1N4148 ), might not be the best circuit but it gets the job done quite well.Decided to post this here in case anyone needed it. would also like to hear what you guys think of it.

author: macboy
author_rank: Super Contributor
timestamp: June 12, 2015, 01:01:06 pm
content: One problem may be that the VBEof Q1 will actually change quite similarly to VFof D1 if both are at the same temperature. So this may work well if D1 is a remote temperature sensor, with Q1 kept relatively cool, but with both mounted in the same hot space, it might not work at all.

author: Refrigerator
author_rank: Super Contributor
timestamp: June 12, 2015, 03:24:14 pm
content: Quote from: macboy on June 12, 2015, 01:01:06 pmYes, as i said it's not the best circuit out there but when the temperature sensor ( diode ) is mounted remotely it does work very well.This circuit from start to full speed gets in about 15oC but if a quick ramp up is needed the second transistor can be modified by connecting the emitter to ground and connecting the fan in between the supply and collector.http://gyazo.com/a938d6d9342c326f5a9762de5edf3482This way the circuit ramps up right when the set temperature is reached but the supply must not exceed the rated fan voltage.

author: dom0
author_rank: Super Contributor
timestamp: June 12, 2015, 04:23:39 pm
content: Quote from: macboy on June 12, 2015, 01:01:06 pmYes, that's in fact a requirement of circuits like these, only one of the BE junctions in the circuit is in contact with whatever has to be kept cool.
I can't find this a supplier. DC Jack Plug with lock - Page 1
Forum section: electronics / projects

author: Opticalworm
author_rank: Contributor
timestamp: October 16, 2014, 08:37:03 am
content: Hello everyone.Digi's sell a wifi server "Wi-Sp Connect" that can be used with a DC jack that can be lock into place. (I've attached an image of the plug".I'm having a hard time finding any information about this plug. To be honest even Digi's website doesn't seem to make any reference to this plug.I'm starting to believe that it's a propriety plug.Does anyone know anything this plug?link to the wifi server:http://www.digi.com/products/serialservers/digiconnectwisp- Ron

author: Kjelt
author_rank: Super Contributor
timestamp: October 16, 2014, 10:56:38 am
content: I know the one where the plastick ring on the start of the connector has a lock.Anyway these kind of connectors are known as : DC JACK LOCKING TYPEIn a quick scan I can only find the pcb mount sockets:http://anacapa.kycon.com/2013Catalogpage/DC%20Power/KLDHCX-0202-x-LT.pdfperhaps if you continu to search you will find it eventually, maybe look for a marking inside of in the device on the socket.looks like Mouser might have something like it:

author: Whales
author_rank: Super Contributor
timestamp: October 16, 2014, 11:40:27 am
content: Homebrew possibility: solder an appropriate washer around the barrel.

author: Opticalworm
author_rank: Contributor
timestamp: October 16, 2014, 11:47:47 am
content: Thank you Kjelt for finding it. I've been searching for security or lock. I kept finding this onesSo plug is made by Kycon.Here the mouser link:http://uk.mouser.com/ProductDetail/Kycon/KLDX-P-0202-A-LT/?qs=sGAEpiMZZMtnOp%252bbbqA002eahyEwoy2pr%252bdw7qIo318%3dand the datasheethttp://www.mouser.com/ds/2/222/kycon_kldx-p-0202-a-lt-342617.pdf- Ron
I cant figure out why I am getting 70VAC instead of 120VAC - Page 1
Forum section: electronics / projects

author: Hextejas
author_rank: Frequent Contributor
timestamp: December 09, 2018, 11:41:32 pm
content: from this wall switch.I wired it exactly the same was as shown on the one attachment, yet when I read the VAC across the 2 bare wires, I get about 70VAC.I made sure that I was getting 120VAC coming in, and the light in the switch comes on.It has a fuse of about 315ma. Is the fuse stealing some of my volts ?It must be something simple.

author: IanB
author_rank: Super Contributor
timestamp: December 09, 2018, 11:50:47 pm
content: Quote from: Hextejas on December 09, 2018, 11:41:32 pmThe switch has an internal light? A neon lamp?Are you sure you haven't wired the lamp in series with the load? That could explain your strange voltage measurement.

author: Hextejas
author_rank: Frequent Contributor
timestamp: December 10, 2018, 12:27:09 am
content: Ian, I dont know how to check if the lamp is in series with the load. I will need to look around and see what I can find. I wired it exactly as shown in the one picture.I found this additional info.

author: Gregg
author_rank: Super Contributor
timestamp: December 10, 2018, 12:49:15 am
content: Hextejas,IanB is correct, 70 volts is about right for a neon lamp. Probably one of the two contacts in the switch is not making proper contact which will in effect put the lamp in series with the load. Take off the switch wiring connectors and check with an ohm meter to ensure both switch contacts work as pictured in the schematic.

author: IanB
author_rank: Super Contributor
timestamp: December 10, 2018, 12:51:25 am
content: Quote from: Hextejas on December 10, 2018, 12:27:09 amAccording to the schematic: if you connect mains neutral to the N/L2 terminal and connect mains live/hot to the L/L1 terminal at the top of the diagram, then when the switch is closed 120 V will appear between the device L/L1 and device L2 terminals at the bottom of the picture. If you are unsure of which terminals are which (or to check for faults), you could detach the switch from the mains and test it with a continuity tester.

author: m3vuv
author_rank: Super Contributor
timestamp: December 10, 2018, 01:40:51 am
content: is it black to black and blew to bits? :

author: ArthurDent
author_rank: Super Contributor
timestamp: December 11, 2018, 02:16:21 am
content: The wiring diagram you show, which is a stock photo, and your actual wiring agrees and seems to be correct.What you should do is disconnect the power cord and use the continuity or ohms function on your multimeter to see where the problem is. Check from the unfused hot to the fused hot terminal to see that the fuse is o.k. and you have continuity. With the switch in the on position check the left side of the switch top to bottom to see if there is continuity then do the same with the right side. You can also check from the cord side top terminal to the top left switch wire. Then check from the cord side bottom to the top right switch side for continuity. That should show where the problem is.
I created an AI to find replacement parts  - Page 1
Forum section: electronics / projects

author: mrburnzie
author_rank: Regular Contributor
timestamp: March 24, 2025, 01:09:09 pm
content: Hi everyone!As AI has been very hot lately, I wanted to try and make something useful for hardware development.That something is the following:https://www.swapmychip.comA tool using AI to find alternative components.I would like to get as much feedback as possible to get a sense of what to do next with this toolFeedback is appreciated:https://www.swapmychip.com/feedback

author: Sariel
author_rank: Regular Contributor
timestamp: March 24, 2025, 02:09:01 pm
content: I find myself as a firefighter. Allways try to put off fires and find replacement for obsolete parts.I find this AI tool to be magnificent.Thank you!

author: mr ed
author_rank: Regular Contributor
timestamp: March 24, 2025, 02:22:54 pm
content: Google is much better on 1 test only. It did not take into much consideration what the device actually is. Seems to do only a part number match.

author: mrburnzie
author_rank: Regular Contributor
timestamp: March 24, 2025, 02:58:20 pm
content: Yes, that is not specified, as it is looking more on the functionality side. Will include that as feedback, thank you!

author: HwAoRrDk
author_rank: Super Contributor
timestamp: March 24, 2025, 03:52:40 pm
content: I tried it, with mixed results.It found 5 alternatives for my example: TI TPS2051C. Two of those were completely different package (DFN vs SOT), so I don't know why they were included. One, MIC2025-1YM, was incorrectly reported as being the same package, but in actuality is not (SOIC). One, AP2141SG-13, was a feasible alternative, but not the exact part number given. It did not take into account matching polarity of an EN input signal (active-high vs active-low). The sibling AP2151 variant has the correct active-high EN polarity, however. Only the one remaining suggestion, an SY6280AAC, is a directly suitable substitute.My verdict: not bad, but not great.Edit:Tried another: TI INA180A3IDBV, SOT23-5 current sense amplifierResults:- INA180A3IDBVT: exact same chip, just tube versus reel- MAX40080AUA+T: not compatible, wrong package (WLP-12, TDFN-12)- MCP6V01T-E/OT: not even a current-sense amp, but a generic op-amp- LT1999-10CMS8#PBF: not compatible, wrong package (MSOP-8)- ZXCT1009E5TA: not compatible, wrong package (SOT23-3, SM8)Complete 100% fail on that one.

author: lokin4areason
author_rank: Contributor
timestamp: March 24, 2025, 05:40:45 pm
content: i use a search engine to find my component(s) or tool(s) i use in multiple fied(s)its a hit and miss at time(s) but get amazing result(s) from around the countryand its free , with no fee associated to it
i decided to build a third hand tool  - Page 1
Forum section: electronics / projects

author: differentcurrent
author_rank: Newbie
timestamp: February 29, 2016, 06:59:00 am
content: hay guys i decided to build a simple third hand tool,https://youtu.be/bqxtBoIG02wfor more videos please subscribe to my channelSent from my SM-N920C using Tapatalk

author: Eng_hassan85
author_rank: Newbie
timestamp: March 01, 2016, 10:21:00 pm
content: I got one ready made from a local hardware store for less than 2 bucks .. but Good Work .. Good Luck
I designed a spindle mount for 2417 CNCs - Page 1
Forum section: electronics / projects

author: IonizedGears
author_rank: Regular Contributor
timestamp: June 10, 2018, 05:17:16 pm
content: I bought one of those cheap chinese 2417 CNC mills and I wasn't happy with DC hobby motor (laughable) included. So I designed a mount for one of these:https://www.ebay.com/itm/500W-Brushless-DC-ER11-Spindle-Motor-Air-Cooled-12000rpm-for-CNC-Engraver-Router/191981099079?hash=item2cb2f71847:g:b9MAAOSwhf1Zo5IgIt's a tight fit for 55mm diameter motors but it was designed to be.Anyway, the file is out there for whoever wants it:https://github.com/IonizedGears/2417CNC-Spindle-Mount
I Designed Feet for old Hewlett Packard test equipment  - Page 1
Forum section: electronics / projects

author: markgreco
author_rank: Newbie
timestamp: July 01, 2021, 04:41:16 pm
content: I have a small collection of HP test equipment often they are missing Feet or trim strips.I have uploaded to Thingiverse several things that should make your life complete.Some have been up for several mounts with ZERO likes or collects. They are all tested.https://www.thingiverse.com/mark_greco/designsLet me know your thoughts.

author: PaulAm
author_rank: Frequent Contributor
timestamp: July 01, 2021, 06:04:47 pm
content: The hard part is finding things, doing a search on HP always ends up with tons of printer and PC garbage.There's a thread [that I can't find right now] where people have contributed stl files for replacement parts. Might be nice to add your link to that thread.Nice looking work.OK, search for topic: Replacement Knobs, Feet and Fittings for Test Equipment

author: Stray Electron
author_rank: Super Contributor
timestamp: July 01, 2021, 06:36:26 pm
content: Quote from: markgreco on July 01, 2021, 04:41:16 pmGood work, but the link isn't working.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: July 01, 2021, 07:14:15 pm
content: The search problem is real. I am sure you would not have designed the feet if you had found the existing designs.Post in the knobs and feet sticky thread to help others find yours.Nice work and keep them coming.
I don't know what I did wrong on this amp. - Page 1
Forum section: electronics / projects

author: Hextejas
author_rank: Frequent Contributor
timestamp: December 27, 2018, 05:53:33 pm
content: I have 2 of them and 1 works and the other doesn't. They are based upon the LM3886.I have done nothing more than apply power to them and then take voltage readings at each of the 11 pins. Plus the heat sink.I know that board A works because I inputted a 1khz sine wave and I could hear it from the speaker. Board B is silent.So here is the schematic and the voltage readings. The HS reading was to the heatsink which touches the metal tab on the LM3886I checked the soldering and it looked ok to this newbie eye. So, I was hoping that someone would take a look at the schematicIn relation to the different pins and say AHA!, here it is.Pin...A......B1......31....312.......0......03.......0....-10.84....-31....-315.....31....316.....0......07.....0......08....-3.....-3.59....-30....-10.810...-1.8...-10.711.....0.....0HS...-31....-31I am forever in your debt.

author: Stuart Coyle
author_rank: Contributor
timestamp: December 27, 2018, 07:44:39 pm
content: I would check if the Zener on the mute output is actually dropping 16V, and make sure that there is more than 0.5mA going through the 10k resistor. Just a guess, but maybe the mute is active.

author: Stuart Coyle
author_rank: Contributor
timestamp: December 27, 2018, 07:46:20 pm
content: Oh, and the other obvious thing to do is swap the amplifiers in the two boards, then you know if it is the board or the amplifier chip which is at fault.

author: Andy Watson
author_rank: Super Contributor
timestamp: December 27, 2018, 08:18:35 pm
content: The voltage at pin 3 is wrong - there should be a connection (somewhere) between the signal ground and the power ground.Perhaps post photos ?

author: Hextejas
author_rank: Frequent Contributor
timestamp: December 27, 2018, 10:23:36 pm
content: Thank you Andy and i will check closer when i get home.

author: bson
author_rank: Unknown
timestamp: December 28, 2018, 03:28:51 am
content: Check PWR_GND vs SIG_GND; the input voltages are completely borked. Check the supply rails. Does anything get hot - what is the idle current consumption? Maybe you reversed a power header or something.

author: Hextejas
author_rank: Frequent Contributor
timestamp: December 28, 2018, 03:13:14 pm
content: Quote from: bson on December 28, 2018, 03:28:51 amThank you bson, I will do what you suggest. But I don't quite know how to do what you suggest.PER_GND vs SIG_ GNDUsing a meter, how do I measur it ?
I Finally Got My Homemade Tesla Coil (Slayer Exciter) Working! - Page 1
Forum section: electronics / projects

author: mcsoftware
author_rank: Contributor
timestamp: April 09, 2019, 03:34:12 pm
content: I finally got my Tesla Coil (Slayer Exciter) working! To see it working (and also see why it wasn't working before), view my youtube video at:I made it from parts I already had (therefore no cost), many of which were recycled parts (removed from other things (such as a non-working UPS)). I previously went through an unbelievable amount of attempts to get it to work, so it is a big relief that it's working now.And, if you haven't seen my first Tesla Coil tutorial video, you can view it at:It also covers a lot of electronics stuff (transformers, transistors, transistor switching circuits, power supply design, etc. - really anything with a coil), circuit simulation, electronics kits nostalgia, etc.
I hacked external PCIe connectivity on the Atomic Pi! - Page 1
Forum section: electronics / projects

author: ginbot86
author_rank: Contributor
timestamp: June 25, 2019, 10:46:09 am
content: Man, this was one of those projects where one thinks "Oh, this'll be easy, just gotta wire it all up"... but everything goes wrong. It took a lot of work and many different attempts, but I was able to break out the PCIe bus from the Atomic Pi, which was originally used by the onboard RTL8111G Ethernet chip. The issue was a lack of any accessible points to add an external connector, but I eventually found a working method.My blog post is here:https://ripitapart.wordpress.com/2019/06/25/atomic-pi-adventures-episode-1-adding-external-pci-express-expansion-by-removing-onboard-ethernet/

author: magic
author_rank: Super Contributor
timestamp: June 26, 2019, 10:14:40 am
content: Sounds funIt may have been stubs and parasitics of the Realtek chip which frustrated your early attempts. At 5gb/s one bit is 4cm long so 1cm stub to the chip and back adds a signal delayed by half bit
I have a hard time finding data on those buck converters...  - Page 1
Forum section: electronics / projects

author: Etna.
author_rank: Newbie
timestamp: May 19, 2025, 07:03:54 pm
content: Hi there!I hope you can help me out. I have these neat LED driver modules and was wondering, if anyone has an idea where to find their datasheet. The SO08 was on a board made by APC. Both are getting 230V 50Hz as input. I hope to learn from it an can design my own driver pcbs. Alternatively I would also appreciate other buck converters that might be easier to purchase and/or get data from.Chip 1 says:MRVL 00187A4W1-SAH2543AMTGChip 2 says:KT02GNCG1X0L.3N1516A1Thanks in advance!Regards,Etna.

author: thm_w
author_rank: Super Contributor
timestamp: May 21, 2025, 12:32:47 am
content: Are these buck LED drivers, isolated or not?You can watch some of bigclives videos, usually they come with similar type of ICs:https://www.youtube.com/@bigclivedotcom/search?query=ledBright Power is one of the common ones, they don't have much on LCSC but you should be able to find equivalent devices if you look in the same categories:https://lcsc.com/brand-detail/112.htmlI don't know if its worth designing your own PCBs as you'll need to source the transformers as well.

author: amyk
author_rank: Super Contributor
timestamp: May 21, 2025, 01:42:55 am
content: First one is a Marvell (yes, seriously) 88EM8187. Couldn't find a datasheet but only a product brief, ironically on this site:https://www.eevblog.com/forum/index.php?thememode=full;redirect=https%3A%2F%2Fwww.eevblog.com%2Fforum%2Freviews%2Fikea-ledare-teardown%2F%3Faction%3Ddlattach%3Battach%3D1496137

author: Etna.
author_rank: Newbie
timestamp: May 21, 2025, 08:10:22 pm
content: Heya!Quote from: thm_w on May 21, 2025, 12:32:47 amSome are, some not... I find it quite funny to use a transformer, just to connect both sides with a diode to get a reference voltage or current.If you got any tips on insulated buck converters that drive some LEDs up to 8W, let me know! I am looking right now through a lot of datasheets.Quote from: thm_w on May 21, 2025, 12:32:47 amHe is the reason I began to destroy those lights in the first place. I've learned a lot so far!Quote from: amyk on May 21, 2025, 01:42:55 amYeah! I've found that already! Do you know the original thread where this is mentioned by any chance?Thanks for your help so far!Regards,Etna.

author: thm_w
author_rank: Super Contributor
timestamp: May 21, 2025, 10:55:24 pm
content: For $5 there is no way I could make a better product than this:https://www.digikey.com/en/products/detail/mean-well-usa-inc/APC-8-500/7702583
I have LM317T, LM723, LM2596, good bench PSU designs ? - Page 1
Forum section: electronics / projects

author: lordvader88
author_rank: Frequent Contributor
timestamp: January 30, 2017, 01:15:51 am
content: I also have prototype breadboard that require solder. So for 1 thing I will take a 24V PSU for a LCD monitor, and an LM317 and make about 2, 3, 3.3, 4.5, 5, 6, 7.5, 9, -12, 12, and maybe some more, and just wire it up with as a bunch of voltage dividers with a minimum current of ~2.5-3mA. I ordered a multi-position switch, so only 20-40 days to wait from China.So for fun I'll make that anyways, I like to solder things. Also what are some other good ideas, past the little designs in them datasheets ?I have solder, breadboards, and time, so this is just for fun

author: KhronX
author_rank: Frequent Contributor
timestamp: January 30, 2017, 01:29:05 am
content: If you use a 100-120resistor for the out-to-adj ("top" of the resistive divider), you can get away with only switching through various bottom-of-the-resistive-divider values.

author: lordvader88
author_rank: Frequent Contributor
timestamp: February 03, 2017, 02:15:11 am
content: What about a really accurate 0.5 amp PSU from those chips ? I have a 120:about 23,19,16,14,12, ... from a 1980s clock/radio with I guess a 1-2W speaker probably. The mains transformer is about 2"x2", as a ballpark figure I assume its just fine for 0.5A output.I also have a few transformers from various SMPS, I should make some SMPS too for things to do. I will in time.
I made a browser tool to visualize switched reluctance motor coil configurations - Page 1
Forum section: electronics / projects

author: dusan
author_rank: Regular Contributor
timestamp: May 16, 2024, 02:05:02 pm
content: I needed a PCB based motor and I needed it to rotate slowly so I needed higher amount of coils/poles than usual 3 coil + 2 poles but it was really hard to wrap my head around it because depending on the sizes and ratios and integer factors it may not even work, or may be chaotic etc... I specifically wanted to go up to 12 coils/poles which gives 144 total combinations out of which only 92 are valid. I chose switched reluctance motor instead of BLDC motor because it feels like it might be less sensitive to low tolerances and janky builds.Here is the tool:https://dvhx.github.io/switched-reluctance-motor-configurator/index.htmlHere are all configurations for given amount of coils/poles:https://dvhx.github.io/switched-reluctance-motor-configurator/combinations.htmlEspecially interesting are combinations where there are multiple coils but can be doubled or tripled, for example:- 6c2p (3 real coils, 6 steps) -https://dvhx.github.io/switched-reluctance-motor-configurator/index.html?coil_count=6&pole_count=2- 9c3p (3 real coils, 9 steps) -https://dvhx.github.io/switched-reluctance-motor-configurator/index.html?coil_count=9&pole_count=3- 12c3p (4 real coils, 12 steps) -https://dvhx.github.io/switched-reluctance-motor-configurator/index.html?coil_count=12&pole_count=3- 12c8p (3 real coils, 24 steps) -https://dvhx.github.io/switched-reluctance-motor-configurator/index.html?coil_count=12&pole_count=8- 12c9p (4 real coils, 36 steps) -https://dvhx.github.io/switched-reluctance-motor-configurator/index.html?coil_count=12&pole_count=9- 12c11p (maximum of 132 steps) -https://dvhx.github.io/switched-reluctance-motor-configurator/index.html?coil_count=12&pole_count=11

author: aliarifat794
author_rank: Regular Contributor
timestamp: May 17, 2024, 06:02:38 pm
content: I was trying this. Do we need to click 'step' to get our final result? I just put some random values and pressed 'step'. The diagram changed according to the parameters and after clicking on 'step' it said 'poles are overlaping'.

author: dusan
author_rank: Regular Contributor
timestamp: May 18, 2024, 04:58:16 am
content: I fixed it. When you change configuration it will now show result immediately. Step button is to see "animation".
I made a new rack for on my workbench - Page 1
Forum section: electronics / projects

author: GerardWassink
author_rank: Contributor
timestamp: September 02, 2017, 07:49:23 pm
content: I made a new rack for my workbench for my most important equipment,click here for a short report.

author: PA0PBZ
author_rank: Super Contributor
timestamp: September 02, 2017, 08:16:10 pm
content: Nice job Gerard, I always spent more time thinking about what to do and how to do it than actually doing it.

author: cdev
author_rank: Super Contributor
timestamp: September 02, 2017, 09:51:32 pm
content: Very nice and solid looking.

author: RoGeorge
author_rank: Super Contributor
timestamp: September 02, 2017, 10:21:17 pm
content: It looks very nice, you should also post a pic here:https://www.eevblog.com/forum/chat/whats-your-work-benchlab-look-like-post-some-pictures-of-your-lab/

author: GerardWassink
author_rank: Contributor
timestamp: September 03, 2017, 05:52:04 am
content: Will do George, thanks!
I made a PCB etching maching! I would love to hear your thoughts - Page 1
Forum section: electronics / projects

author: tuvtuv
author_rank: Contributor
timestamp: July 01, 2019, 10:47:35 am
content: here is a link to our blog:http://fenneclabs.net/index.php/2019/06/29/the-complete-pcb-etching-station/

author: capt bullshot
author_rank: Super Contributor
timestamp: July 01, 2019, 11:19:48 am
content: Nice job.I wouldn't build such a thing for my own use, I don't like to mess around with "wet" stuff and always be worried about leaks and such.

author: Benta
author_rank: Super Contributor
timestamp: July 01, 2019, 05:21:22 pm
content: A better solution is a vertical bath with bubble tubes at the bottom, where the PCBs hang vertically into the bath from the top.

author: MosherIV
author_rank: Super Contributor
timestamp: July 01, 2019, 07:38:54 pm
content: Actually spray etching is by far the better methodhttps://hackaday.com/2012/02/11/create-pcbs-in-just-minutes-with-this-awesome-spray-etching-machine/Orhttps://www.instructables.com/id/The-Etchinator-low-cost-spray-etcher/

author: excitedbox
author_rank: Regular Contributor
timestamp: July 02, 2019, 10:51:46 am
content: I am working on a PCB printer that will print multilayer and dual sided pcbs on unclad FR4 / anything you can get the ink to stick to. Just today I received a big shipment of chemicals for producing the nano particles for the conductive inks and in the coming week or two I should have most of the other things I need.

author: hv222
author_rank: Regular Contributor
timestamp: July 02, 2019, 05:31:15 pm
content: Spray etching is most effective. I'm using vertical etching and it do the job.To eliminate Cl2 gas just start with CuCl2 and HCl solution. Let them etch copper. Then add H2O2 to recombine CuCl to CuCl2. Cl2 gas freed can happend when you don’t have enough CuCl in solution (enough copper to etch).Etch solution work best, when CuCl concentration is between 260g/l to 370g/l. For PCV container etch temperature should be lower then 55*C and for PP less then 70*C. HCl in solution is important to get pH below 1 and to dissolve CuO, because CuCl2 don’t each CuO. Concentration of free HCl in solution should be 0.1N to 3N. Best etch results are from 1N to 2N.At this conditions you should etch 35um PCB board in less then 2 minutes. Etching at low concentration of CuCl2 extend etching time and this cause a overetch.To regenerate solution you need add 1.6l of 35% H2O2 and 3.21l of 30% HCl and 3.61l of water for each kilogram of etched copper.
I Made a RGB Human Circuit  - Page 1
Forum section: electronics / projects

author: noah4546
author_rank: Newbie
timestamp: January 14, 2015, 04:57:14 pm
content: I made an rgb led human circuit and I wonder if you could explain how this works Dave. (Well how the tansistor read works not the output of led)http://www.instructables.com/id/RGB-Human-Circuit/
I made an audio-reactive helmet for a sci-fi film (Arduino, Ableton) - Page 1
Forum section: electronics / projects

author: daniel.aagentah
author_rank: Newbie
timestamp: February 02, 2023, 05:25:57 pm
content: Hi all. It's first post in this forum, thought I'd share something I've been working on!I've been delving into the world of electronics the past few months, slowly working towards this project. This year, we're making a short sci-fi film here in Manchester. I thought it'd be cool to design an interactive helmet—something that I can tie into my other audio-visual projects. This IND7 works with Ableton over an Arduino to display MIDI-triggered values on it's 7-segment display.If anyone has worked on something similar, I'd love to share some ideasBig ups,Dan x

author: coromonadalix
author_rank: Super Contributor
timestamp: February 02, 2023, 05:31:21 pm
content: make a look a like daft punk helmet display ??nice and good work

author: RoGeorge
author_rank: Super Contributor
timestamp: February 02, 2023, 10:00:19 pm
content: Wow, great retro Cyberpunk look!
I made LC oscillator finder (and found that there are only 12 simplest types)  - Page 1
Forum section: electronics / projects

author: dusan
author_rank: Regular Contributor
timestamp: July 08, 2024, 11:05:10 am
content: I made a program that generate random topology and uses spice simulation to find if it oscillate. The goal was to find some novel LC oscillators. It worked, it found many different oscillators. I let it ran for a while and soon I found out that the simplest possible LC oscillator has 1 inductor, 2 capacitors, 1 resistor and 1 transistor. I found many different variations of it, I called this class of oscillators "LCCRT oscillator" and it also always had 2 internal nodes so that's not very large search space so I generate all possible combinations and I found out there are exactly 12 distinct LCCRT topologies:Basically any time cap connects to a rail it can be placed to other rail as well, and any time one rail connects via resistor, the resistor can also be moved to other rail. This creates 12 possible combinations.Of course it found many different topologies. Some times they were unique, other times they could be simplified into already found oscillator. You can find entire project on github, it is a ngspicejs script:https://github.com/dvhx/lc-oscillator-finder

author: Shay
author_rank: Regular Contributor
timestamp: July 12, 2024, 06:36:05 pm
content: That's really cool. Is it able to generate other type of oscillators? E.g some that rely on negative resistances or simpler R/C/BJT only type?

author: dusan
author_rank: Regular Contributor
timestamp: July 13, 2024, 07:02:15 am
content: Currently only one inductor and any amount of capacitor, resistor and npn.
I need a bit of help with touchscreen coordinates on mcufriend display - Page 1
Forum section: electronics / projects

author: muscleleaf
author_rank: Newbie
timestamp: January 16, 2019, 12:35:54 pm
content: Hello EEVlog community.I am sorry if this is not the right location to post. I am working with an mcufriend 3.5" TFT Touchscreen display on an Arduino Mega using the mcufriend_kbv library. I got everything working fine, things draw properly, all that crap but I cannot for the life of me get the touchscreen to work as intended. The X and Y are mirrored as hell. I press left it goes right and vice versa.In my project I have:#define XM A1 // must be an analog pin, use "An" notation!#define YP A2 // must be an analog pin, use "An" notation!#define XP 7 // can be a digital pin#define YM 6 // can be a digital pinand in the loop()xpos = map(tp.y, 210, 902, 0, tft.width());ypos = map(tp.x, 859, 213, 0, tft.height());I have gotten these values by running the mcufriend_kbv calibration thing. The calibration worked fine, I was able to press the crosshairs correctly and it printed this to serial:TouchScreen.h GFX CalibrationMaking all control and bus pins INPUT_PULLUPTypical 30k Analog pullup with corresponding pinwould read low when digital is written LOWe.g. reads ~25 for 300R X directione.g. reads ~30 for 500R Y directionTesting : (A1, D7) = 21Testing : (A2, D6) = 31Diagnosing as:-XM,XP: (A1, D7) = 21YP,YM: (A2, D6) = 31ID = 0x6814cx=286 cy=363 cz=139 LEFT, TOP, Pressurecx=247 cy=565 cz=138 LEFT, MIDH, Pressurecx=170 cy=918 cz=238 LEFT, BOT, Pressurecx=523 cy=157 cz=630 MIDW, TOP, Pressurecx=529 cy=917 cz=342 MIDW, BOT, Pressurecx=882 cy=156 cz=702 RT, TOP, Pressurecx=887 cy=533 cz=570 RT, MIDH, Pressurecx=748 cy=830 cz=437 RT, BOT, PressureMCUFRIEND_kbv ID=0x6814 320 x 480const int XP=7,XM=A1,YP=A2,YM=6; //320x480 ID=0x6814const int TS_LEFT=213,TS_RT=859,TS_TOP=210,TS_BOT=902;PORTRAIT CALIBRATION 320 x 480x = map(p.x, LEFT=213, RT=859, 0, 320)y = map(p.y, TOP=210, BOT=902, 0, 480)Touch Pin Wiring XP=7 XM=A1 YP=A2 YM=6LANDSCAPE CALIBRATION 480 x 320x = map(p.y, LEFT=210, RT=902, 0, 480)y = map(p.x, TOP=859, BOT=213, 0, 320)I am using the display in the landscape orientation number 1.I have tried swapping around the defined pins and it changes stuff but still not what I need, it makes it believe up is left and down is right and stuff like that. I think I've rotated those values in all possible ways. Any ideas why it flips right and left? I am using the standard drawing sketch by mcufriend_kbv and when I draw in the left corner it draws in the right one.Thanks a lot for your help, this has been driving me mad for the past week
I need a DAQ - Page 1
Forum section: electronics / projects

author: cncjerry
author_rank: Unknown
timestamp: January 31, 2020, 09:29:11 am
content: More like a want one. I've been looking at some of the new Analog devices boards and the AD4110 and the Analogmax daq1.Both just don't do it for me. I thought the Ad4110 eval was decent at $99 USD but then I guess you need the system development platform board I think it is called, the interface between the board and PC, and that is another $50.Then I started looking at the Hantek products and Picoscope, Analog Discovery and other products like those. I posted here because the application would drive the need. I don't need it to generate anything as some of those units have signal generators. I would like it to be 24 bit and sampling needs to only be 100 per second though faster is ok. I can live with 20 bits. I don't need fancy software as all the processing is offline. Ideally I want to hook my lab freq reference to it and an external voltage reference. I thought about building my own like the AD4110 and might still go that route. It will be used for time and phase related experiments initially, measuring some very low frequency and phase differences. I saw that Owon 6112and that looked interesting with averaging and ET it looked like it got to 13bits only.Thoughts?

author: DaJMasta
author_rank: Super Contributor
timestamp: January 31, 2020, 10:49:31 pm
content: A DAQ or an ADC?There are a number of USB DAQs in various configurations, but if you want 20 bits at 100 samples a second..... you just need a decent DMM. Something like a 6.5 digit DMM should give you around that without PLC averaging and reading to memory or over an external interface can probably get you 100 samples a second. A Keithley 2000, for example, can be pretty cheap on the used market and can give you 5.5 digits of resolution to about 270 samples a second over GPIB.If you relax your number of bits requirement a bit, NI or Measurement Computing both make 14-16 bit USB DAQs with several channels and much higher sample rates, then many other companies make similar products (I think Dave's even showed a couple on the mailbag). There's also the PXI or similar mainframe option if you're willing to invest in a chassis and controller as you can get high sample rates, high resolution, or both for relatively reasonable prices, and there's availability for many measurement channels at once.On the cheap end of things, if you can limit your input signal range, audio ADCs are commonly 24 bit with 96kHz or more sample rate and are very cheap as consumer items. With the right input circuitry to keep it within range and with a decently laid out commercial board, you can achieve some pretty low noise and high accuracy with your regular audio card as an input.

author: thm_w
author_rank: Super Contributor
timestamp: February 01, 2020, 12:22:52 am
content: https://www.picotech.com/data-logger/adc-20-adc-24/precision-data-acquisitionhttps://labjack.com/All-Categories/24bit-analog-input-daq
I need a good 555 project ASAP (Please) - Page 1
Forum section: electronics / projects

author: thomieboy
author_rank: Contributor
timestamp: March 26, 2014, 08:13:16 pm
content: Hello everybody,I'm a 16 year old student and for my electronics class I need to make a simple but fun 555 timer project.I don't know what to choose. I need an orignal project that is not too expensive to make and is relativly easy to explain.Next tuesday I have to present it too my teacher for my exam. After spring break we will have to order the parts and make it.Anybody here with good idea's? I already found this website:http://www.555-timer-circuits.com/There are a few projects on that, but to be honnest, I would like that mine stand out a bit.Thanks in advance !

author: oldway
author_rank: Super Contributor
timestamp: March 26, 2014, 08:57:31 pm
content: I am working on a dimmer for controling highly inductive loads using two 555 (Cmos version) to generate pulses for the triac.It's intended to work on main (230Vac), but for safety, it could be used with 24Vac.That's an original project, you will not find this on Internet.What do you think about ?

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 26, 2014, 09:00:53 pm
content: Search 555 timer contest for ideas.

author: thomieboy
author_rank: Contributor
timestamp: March 26, 2014, 09:02:18 pm
content: Quote from: oldway on March 26, 2014, 08:57:31 pmThis is indeed original, I will keep this one in mind. Thank you !

author: oldway
author_rank: Super Contributor
timestamp: March 26, 2014, 09:12:54 pm
content: It is already working, I still have to make some improvements as soft start.Using:- 01 x LM324 (micro power 4 x op amp)- 02 x TLC555 (cmos version of 555)- 02 x BC337 (NPN transistors)- 01 x BC327 (PNO transistor)- 01 diode zener 15V 1W- 01 diode 1N4007- 02 diodes 1N4148The only problem is that your teacher will never believe that you have make this project...Here, another one more simple:http://www.edn.com/design/analog/4415447/555-timer-triggers-phase-control-circuitFor safety, you only have to modify this project to work with 24Vac instead of 230Vac.

author: GiskardReventlov
author_rank: Frequent Contributor
timestamp: March 27, 2014, 01:15:08 am
content: In no specific order.Code:1) model the diurnal cycle2) model the gestational period for your favorite invertebrate3) model the gestational period for your favorite mammal4) egg timer5) teeth brushing timer6) bacterial growth curve7) battery charge curve8) battery drain curve9) model the time it takes for a car salesperson to cause you to flee the car lot10) model radioactive decay11) model orbit for Halley's Comet
I need a manual for national Panasonic vp5102b - Page 1
Forum section: electronics / projects

author: Mugiwara303
author_rank: Contributor
timestamp: January 18, 2022, 07:08:56 pm
content: Hi everyone, I need a manual for national Panasonic vp5102b oscilloscope I couldn't find it on google, thank you.

author: Benta
author_rank: Super Contributor
timestamp: January 18, 2022, 08:04:26 pm
content: Quote from: Mugiwara303 on January 18, 2022, 07:08:56 pmWrong. It's the second hit on Google.What you mean is: "I couldn't find it FOR FREE anywhere using Google."That's a different story.
I need feedback on this project - Gas sensor - Page 1
Forum section: electronics / projects

author: LuisHDR
author_rank: Newbie
timestamp: August 06, 2025, 08:13:55 pm
content: Hi everyone, I’m an electronic engineering student and have been working for a while with datasheets, application notes, programming, and PCB design using KiCad.I’m currently working on a small gas sensor module, similar in concept to the MQ series, but based on a higher quality sensor from Figaro. I’d really appreciate any feedback, as I don’t have someone close I can ask for input on the design.The idea is that the module outputs between 0V and 2V, using an INA333 instrumentation amplifier. I’ve included a potentiometer to allow offset adjustment at the input.So far, I’ve tested the Wheatstone bridge output with a multimeter on a breadboard, and I can adjust the signal down to around 0.050 mV. It seems to oscillate between 0.050 mV and 0.400 mV. With the INA333 set to a gain of ~20, the maximum differential signal of ~100 mV should give me an output of 2V.The circuit also includes a 3.0V voltage regulator, which is what the sensor requires — and I’m powering the INA333 from the same regulator.Any comments, suggestions, or concerns would be greatly appreciated. Thanks in advance!test1 and test2, is for set offset input, with multimeter.

author: daisizhou
author_rank: Super Contributor
timestamp: August 06, 2025, 10:50:25 pm
content: You can try the MAX1452 solution.INA333 is a differential amplifier circuit, and using a more modern MAX1452 might be better.

author: MariuszD
author_rank: Regular Contributor
timestamp: August 07, 2025, 06:59:45 am
content: Remove C1 because it causes instability, remove R4 because it serves no purpose.

author: LuisHDR
author_rank: Newbie
timestamp: August 07, 2025, 02:40:29 pm
content: Quote from: MariuszD on August 07, 2025, 06:59:45 amAfter reading a bit, I realize I could do without the resistor, but wouldn't it be better to keep the capacitor to filter out noise

author: MariuszD
author_rank: Regular Contributor
timestamp: August 07, 2025, 04:48:00 pm
content: Capacitive loading causes oscillations in the amplifier. Filters are made differently.
I need help converting frequency to time. - Page 1
Forum section: electronics / projects

author: MarkS
author_rank: Unknown
timestamp: February 07, 2012, 04:56:38 am
content: I've never had the need before and I want to make sure I've got this correct.For my 68000 computer, the processor needs a power on reset delay equivalent to 128 clock cycles. I'm using a 10 MHz clock. If my calculations are correct, I get 0.0128 ms. I'm calculating it like this: 0.0000001 * 1000 * 128. Is this correct?

author: ron
author_rank: Regular Contributor
timestamp: February 07, 2012, 05:05:18 am
content: freq=1/period

author: amspire
author_rank: Super Contributor
timestamp: February 07, 2012, 05:13:35 am
content: Sounds correct to me.