hybridfree/eevblog-posts huggingface dataset:
Searching for rocker, buttons and connectors for underwater product housing - Page 1
Forum section: electronics / projects

author: Jackster
author_rank: Frequent Contributor
timestamp: January 14, 2023, 12:33:08 pm
content: Very early stages of a POC bit of work for an underwater housing with some electronics in it.I require some button/rocker switches and power/data connectors for underwater applications.Notting crazy like 1000+ ft down but around the 300-500ft mark plus overhead.Mostly after buttons that are small enough to fit a few in a small space. Thinking 3-5mm rounded.But also need some that are 5-10mm round.The rocker needs to be large enough for thumb use with neoprene gloves on.Think camera zoom rocker with the ability to press on it a little or a lot with analog voltage so I can see how far the rocker is pushed.As for connectors. I am ideally looking for power and coax in a single connector but can settle for two connectors.Any suggestions on brands to go with?Most of my searches so far have turned up massive industrial ones or cheap "water proof" ones.Ideally looking for suggestions from people who have used connectors underwater. I have found a few suppliers.

author: geggi1
author_rank: Frequent Contributor
timestamp: January 14, 2023, 01:01:07 pm
content: I think that at these pressure ranges everything is custom. About 10 to 15 bar overpressure.From your picture it looks like its for something camera related.There are under-water housings for for some cameras on the marked

author: Terry Bites
author_rank: Super Contributor
timestamp: January 14, 2023, 04:24:24 pm
content: Like this?https://chaloncomponents.co.uk/product/ek1-waterproof-cover-for-a11-rocker-switch/30barwww.lemo.com/en/products/high-pressure-connector

author: Jackster
author_rank: Frequent Contributor
timestamp: January 14, 2023, 05:14:17 pm
content: Quote from: Terry Bites on January 14, 2023, 04:24:24 pmYes, like those connectors.Forgot to check Lemo. Already use them on another product..I doubt those caps will work under pressure.

author: bidrohini
author_rank: Regular Contributor
timestamp: January 15, 2023, 02:23:13 am
content: For push buttons you can visit:https://www.roboticocean.com/product/pressure-rated-switch/
Searching for SMD Top to Bottom connector - Page 1
Forum section: electronics / projects

author: Jannehrl
author_rank: Contributor
timestamp: April 06, 2020, 08:06:40 am
content: Hello Guys,im coming with a special request - im searching for a a simple SMD Connector that you can place on top of a PCB, but will connect to a connector at the bottom. You dont know what i mean? Well its a bit difficult to explain in text, thats why i made a little sketch of what would suit my needs( SMD Header connector, i didnt draw the body).I need a connector for my Aluminium PCB`s (Aluminium = 1 Layer only) where i want to connect LED`s on top of the PCB to a PCB under that aluminium PCB.I did search for such a connector, but honestly i dont even know what to search for (270 Degree connector? upside-down connector?).Looking forward to your replies

author: veryevil
author_rank: Unknown
timestamp: April 06, 2020, 07:01:19 pm
content: Tryhttps://www.digikey.co.uk/short/zjb30c

author: max_torque
author_rank: Super Contributor
timestamp: April 07, 2020, 01:17:48 pm
content: can you drill / mill through your IMS pcb? If so, "surface mount, bottom entry" are the key words..........https://www.google.com/search?q=surface+mount+bottom+entryObviously, you'll need a tight enough geometrical tollerance on the two pcbs to stop the pins that come up from the lower pcb, and through the top pcb actually touching and shorting on the IMS of that pcb

author: Wendy_Preston
author_rank: Contributor
timestamp: April 09, 2020, 07:43:02 am
content: Could you just use a horizontal THT pin header, but mount the tails SMT sideways, giving you the mating pin facing down?If so, then you just need to determine if the pitch and pin size you need is available as a standard pin header. You'll probably need to glue or support the header before soldering, obviously.

author: TomS_
author_rank: Frequent Contributor
timestamp: April 10, 2020, 01:07:33 am
content: Some people have already mentioned it, but yeah, you need to flip your thinking 180.On the board where you want the pins, use a bottom entry socket instead, and then place the pin header on the other board.The bottom entry socket mounts on the top of the board like you want, and holes are drilled to allow the pins to poke through from below.Search google images for "bottom entry socket" and you'll find some examples of how it fits together.

author: donotdespisethesnake
author_rank: Super Contributor
timestamp: April 12, 2020, 03:54:17 pm
content: I have four questions:1. Is the connector intended to be edge mount, or anywhere on the board? i.e. can the substrate be drilled or routed?2. What is the current and temperature rating required?3. Surely this is a common requirement, how do other people do it?4. Will we ever hear from the OP again?

author: Jannehrl
author_rank: Contributor
timestamp: April 21, 2020, 09:06:35 am
content: I didnt think id get that many answersthank you allThe tip about "Bottom entry" is pretty much exactly what i needed.I really didnt know that most smd Pin Headers can be simultaneously used for bottom entry.That pretty much solved my problem.
Searching for Step up LED driver  - Page 1
Forum section: electronics / projects

author: ranthalion
author_rank: Contributor
timestamp: December 24, 2020, 05:22:11 pm
content: I'm looking for something similar toPR4401 - Boost Driver for LEDs, but available through one of the big distributors (Mouser, Digikey, Arrow, LCSC). This Prema IC is SOT23-3 and only requires a small 10-47 uH inductor to drive an LED from 0.9 volts. The downside is that it's not available from the typical distributors I'm aware of.Is there a similar component in terms of functionality, size, cost, and additional components? I've spent some time browsing through Digikey and Mouser, but I haven't found anything that works with only a single additional component.

author: Marco
author_rank: Super Contributor
timestamp: December 24, 2020, 09:32:16 pm
content: I googled for "three pin" boost led driver, which got me to astackexchange post, which mentioned theZXSC380from Diodes Inc available at Mouser and Digikey (and CL0117, which is not).

author: ranthalion
author_rank: Contributor
timestamp: December 25, 2020, 12:31:14 am
content: Awesome! Thanks so much for that recommendation.
Searching for Thumbstick Joystick - Page 1
Forum section: electronics / projects

author: DocRaptor
author_rank: Contributor
timestamp: February 01, 2025, 04:37:06 pm
content: Hello,I'm looking for thumb joysticks, which are available at digikey, mouser or lcsc. It needs to be a flat type one like the N40P107 and needs to be hall effect or resistive, not the "simple" push buttons style. The problem is: It is like every company discontinued this type. AMS N40P107, ALPS RKJXU, ... , all listed as obsolete. Is there a thumb joystick out there, which is compact, pcb mountable and available by the big distributors?

author: coppice
author_rank: Super Contributor
timestamp: February 01, 2025, 05:05:46 pm
content: The ALPS RKJXV is resistive. Is that unsuitable in some way?

author: DocRaptor
author_rank: Contributor
timestamp: February 01, 2025, 06:19:52 pm
content: Quote from: coppice on February 01, 2025, 05:05:46 pmThe problem is: It is not compact. The high of the ALPS RKJXV is 2cm. I need a low profile like the N40P107 with 4.33mm or the ALPS RKJXU with 6.7mm .

author: Marco
author_rank: Super Contributor
timestamp: February 01, 2025, 06:42:09 pm
content: How about Nintendo Switch third party replacement part? It will be hard to find the actual manufacturer, but availability is likely not going away soon.

author: DocRaptor
author_rank: Contributor
timestamp: February 01, 2025, 08:33:38 pm
content: Quote from: Marco on February 01, 2025, 06:42:09 pmThe Switch Joysticks stick to out much. My project will be housed in a clamshell case. The most fitting thing only is this one:https://www.digikey.de/de/products/detail/adafruit-industries-llc/2765/6193582. Or if I hunt them at Aliexpress the FJ08K-S / B10K-1. Sadly nothing hall-effect.It is weird. There where multiple manufactures who made these thumb joysticks. Now there is really no one.

author: SiliconWizard
author_rank: Super Contributor
timestamp: February 02, 2025, 02:30:09 am
content: On Aliexpress you can find replacement for the Nintendo Switch which are claimed to be Hall-effect based, such as:https://www.aliexpress.com/item/1005006746686389.htmlIt's hard to find out what the manufacturer of these is. The brand name that is given on Aliex (here: BIKLY) is usually the name of the brand which sells the replacement kits (joysticks + screwdrivers + ...)Haven't found these tiny ones on Digikey or Mouser, but I'd be interested too.

author: DocRaptor
author_rank: Contributor
timestamp: February 02, 2025, 11:43:34 am
content: Quote from: SiliconWizard on February 02, 2025, 02:30:09 amIt looks like the Manufacturer of one of the Switch replacement joysticks is YTL. On LCSC they offer two joysticks, which are looking like the ones from the Switch. The LCSC Part numbers of these are C42411045 and C42411052.
Searching for USB GPS - Page 1
Forum section: electronics / projects

author: marholt
author_rank: Newbie
timestamp: September 08, 2015, 11:38:21 am
content: I'm looking for USB gps, that has accurate data for the altitude and position.I tested from Columbus V-800 +. The test was performed on octokopter with a autopilot. On the drone, there is also an internal GPS, which I've compared columbus to. In addition, I also mounted my phone and logged the data using sport tacker application. Columbus has a very poor results (see attached graph blue line.) The red line on graph is a programmed route of which would be ideal, but the actual route is green line. Even when I comparede with the phone, the information on an internal GPS and on the phone very similar.I've also contacted columbus why is there so much differences betwen the data, but there was no answer from them.I don't want to use the internal GPS because of 2 reasons:It has communication via the CAN bus and it's own protocol, for which there is no documentation, and I do not know if decoded it correctly, because sometimes I get false information.If I'm connected to CAN bus with non standart equipment for the drone, I can't guarantee that this will not interfere with the autopilot. (Problem with insurance if the drone crashes)So I'm looking for a suitable USB gps, where there is sufficiently accurate data for altitude. If it also includes air preasure correction for altitude measurement, even better.It may also be on the RS232 bus.Does anyone have any suggestions?

author: dave_k
author_rank: Frequent Contributor
timestamp: September 08, 2015, 12:26:25 pm
content: Have you looked at any of the modules from uBlox?

author: matkar
author_rank: Regular Contributor
timestamp: September 08, 2015, 06:59:16 pm
content: It seems like the Columbus GPS has data averaging... What is the time scale on your chart?I wouldn't worry about CAN interference too much since you only read the data. It seems you figured out the protocol correctly. Could those occasional glitches you mention not come from misreading CAN but erroneous altitude measurements? You can further configure your CAN reader in "listen only" mode so it doesn't interfere with CAN at all.What kind of CAN reader do you have?

author: marholt
author_rank: Newbie
timestamp: September 09, 2015, 05:15:01 am
content: For CAN reading and decoding I'm using bealgebone. It is possible that beaglebone causes those glitches.So I can buy a new CAN reader and stil wonder if I decoded the protocol correctly or buy a new GPS.
Searching for waterproof connector for module that connects to panel. - Page 1
Forum section: electronics / projects

author: Jackster
author_rank: Frequent Contributor
timestamp: January 17, 2022, 09:45:54 pm
content: Hi allBeen tasked with finding a connector series that will allow for a module to connect to a panel and also connect via a cable using the same connector.So need a female panel socket, male plug, female plug, male panel socket.With both panel sockets being able to mate.Only need 5 pins, and ideally needs to be in the 10-20mm diameter range of size.Also can not be like $20 per connector. Looking for something on the lower end of the price range.ThanksJack

author: mc172
author_rank: Frequent Contributor
timestamp: January 17, 2022, 11:41:37 pm
content: The SP13 range is something I've used in the past for outdoor projects. They're available cheaply on Amazon/eBay/etc.

author: jpanhalt
author_rank: Super Contributor
timestamp: January 17, 2022, 11:44:28 pm
content: Look at the range of connectors for automotive use. Relatively small, easy to use, and waterproof.
Searching for white led backlight for lcd display 150x50mm - Page 1
Forum section: electronics / projects

author: Kjelt
author_rank: Super Contributor
timestamp: October 24, 2021, 02:44:56 pm
content: Anyone here maybe know where to buy these ?I need to replace a CFL backlight preferably with a white led backlight, something like this but then bigger, 150mmx50mm 3mm thick good diffusion.Thanks,https://www.adafruit.com/product/1621

author: tooki
author_rank: Super Contributor
timestamp: October 25, 2021, 06:10:41 am
content: Following. I’ve also had little luck finding larger backlight modules.For what it’s worth, something I bought the parts for but haven’t put together yet is using a COB LED module as the backlight. They come in many different shapes, sizes and voltages. While they’re intended for high currents for illumination, one can of course run them at a fraction of their maximum current to get a backlight-friendly light flux.

author: voltsandjolts
author_rank: Unknown
timestamp: October 25, 2021, 09:54:48 am
content: Two 75x60mm side by sidehttps://www.luckylight.cn/en/products/led-display/led-backlight/

author: Kjelt
author_rank: Super Contributor
timestamp: October 31, 2021, 09:49:59 am
content: It looks like it is unobtanium
Searching for Zuken Cadstar download - Page 1
Forum section: electronics / projects

author: mikecarts
author_rank: Newbie
timestamp: December 05, 2013, 06:16:59 am
content: Good day to all,Can anyone help me on where to download Zuken Cadstar software?I did find one in but seems like theres a problem with the software due to comments posted.Is this a free software? or licensed required. I will be using this for my personal use and for my knowledge to explore and practice.Looking forward on your response.Thanks.

author: poorchava
author_rank: Super Contributor
timestamp: December 05, 2013, 08:07:07 am
content: Here:http://www.zuken.com/en/products/pcb-design/cadstar/resources/expressYou need to register first.Express edition is limited to 300 pins or 50 components. This can be worked around by creating components that are in fact "circuit modules", but it's very cumbersome on larger scale. Also CadStar in general is a rather unpleasant tool to use. It has all the features that other high-end packages have, but the interface sucks bigtime. PCB designers in our company use it. If you can afford the full version - dont buy CadStar, go for Altium. If you're gonna use it as a hobbyist better go for DipTrace, because it's a piece of software that a hobbyist can actually afford.Or you can look on torrent sites.

author: mikecarts
author_rank: Newbie
timestamp: December 05, 2013, 08:36:46 am
content: Thank you SirAs per your advice I will take it as my reference.I have experiences with Eagle but I need to migrate on a recommended EDA software that is widely used in the electronics industries specially those companies who used it.I have read some comments and opinions about Altium sounds interesting on my part coz its well recommended

author: LEECH666
author_rank: Frequent Contributor
timestamp: December 05, 2013, 01:37:15 pm
content: Cadstar is quirky indeed. If you're not dead set on it I wouldn't recommend it either.I have to use it at work and you get used to it.
Searching info about this synchro converter - Page 1
Forum section: electronics / projects

author: F4CPY
author_rank: Contributor
timestamp: April 25, 2014, 02:17:37 pm
content: Hi guysI'm on a antenna rotator project using synchros for antenna position recopy.I found a part in my local junkyard which can perhaps be used.I join a (bad) photo sorry for the blur.It's a DDC (data device corp.) conversion module SC-471Pins: S1, S2, S3 for the synchro.GND, 15v, -15v, 5v ok for the supplyBut what about V, M, S, -CI suspect S as sinus, -c as -cosinus, but V and M? (Velocity, Motion?).Tried to search at DDC website for old part but see nothing about SC moduleMy first guess will go on a sort of SCOTT T transformerhttps://plus.google.com/101722425550171060516/posts/fWroqUndMwAThanks for your helpDidier

author: woodchips
author_rank: Frequent Contributor
timestamp: April 25, 2014, 02:50:47 pm
content: If the modules are just Scott transformers, then no power supplies are needed, so must be more than that.What about a synchro to serial data converter? So need clock, start, ? and ? pins?Analog Devices make (still do?) resolver to digital converters, but not synchro to digital, always seemed to convert resolver to synchro first.The module might be a special to Sperry item, but must be for gyro compasses?Might have to buy them and try.
Searching simple wireless audio solution - Page 1
Forum section: electronics / projects

author: PeterFW
author_rank: Frequent Contributor
timestamp: May 10, 2015, 01:28:51 pm
content: Hello!Are there simple drop in solutions available to transmit two line level signal wirelessly?Not a complete consumer product, something like a ESP8266 or XBee but for audio.Idally without PCB antenna, i would like to use a proper one.Bluetooth is not an option, it should be low latency and only require line level in and outputs.The only ones i could find were I2S.Greetings,Peter

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: May 10, 2015, 01:39:36 pm
content: Isn't that called FM radio?

author: technix
author_rank: Super Contributor
timestamp: May 10, 2015, 01:46:12 pm
content: Simplest solution for audio frequencies with existing modules: FM radio.Get one of those in-car stereo FM transmitters and a stereo FM radio, tune them to the same frequency that is not used in your local region, and you are good to go for a few tens of meters of reception range.If you want larger range, get a HAM radio certificate.

author: PeterFW
author_rank: Frequent Contributor
timestamp: May 10, 2015, 02:19:22 pm
content: Should have said that more explicit, something digital/paired with a decent frequency response

author: Marco
author_rank: Super Contributor
timestamp: May 10, 2015, 02:50:42 pm
content: Microchip has Kleer and Dialog Semiconductors has Smartbeat, but they aren't interested in selling individual modules.Ti Purepath is probably your best bet, althoughmodules aren't exactly cheap.PS. oops, you wanted line in ... the development kit modules can do that, butthat's even less cheap.PPS. there's quite a few different Chinese boards with the NRF24Z1 available from the usual suspects as well.

author: technix
author_rank: Super Contributor
timestamp: May 10, 2015, 04:20:55 pm
content: Quote from: PeterFW on May 10, 2015, 02:19:22 pmDigital audio always have some kind of delay when passing through processors, and you are using two processors here - this will almost certainly throw off timing and ruin your experience if you need time sync (e.g. video playback)FM is the cheapest and simplest actually, with decent frequency response.

author: Marco
author_rank: Super Contributor
timestamp: May 10, 2015, 04:29:01 pm
content: A couple of 10s of msec this way or that aren't going to ruin it ... synchronization of A/V on PCs is piss poor and people rarely notice.
Second and third sourcing components - Page 1
Forum section: electronics / projects

author: Pack34
author_rank: Frequent Contributor
timestamp: October 05, 2016, 02:51:30 pm
content: I'm about to go through my product portfolio and add substitutes for all of my BOMs. How "deep" should I go? Is just a single substitute fine, or should I add a second substitute?It seems like every-time I send something off I have a random capacitor that's out of stock for 7 weeks. I'd like to do this as professionally as possible but I wasn't sure if a single substitute would be fine.

author: Pack34
author_rank: Frequent Contributor
timestamp: October 05, 2016, 03:12:40 pm
content: With the current assembly process we have in place, everything is locked down and requires forms to be exchanged when substitutions are made. Currently I'm attributing the primary source and manufacturing part numbers for all components in the BOM.The concern is that every other batch there's a random component that is out world-wide. The assembler contacts our manufacturing manager, forwards me the email, I check off on the substitute, sign and scan a form, and then they make the boards.Picking out multiple acceptable parts will not be an issue. It's just that this depth of BOM management is a bit new to me and I do not know if just a single alternative is fine or if I should have two or three alternatives (when possible) just to be sure everything runs as smooth and is as hands-off as possible.I'd rather be looking at new products than filling out forms for issues with stuff that's been locked in for a year or more.

author: Cerebus
author_rank: Super Contributor
timestamp: October 05, 2016, 03:15:49 pm
content: Quote from: blueskull on October 05, 2016, 02:58:53 pmYou've told him lots he probably already knows but you haven't answered the only actual question he asked:QuoteI'm sorry to say I haven't anything useful to say on "how deep", but at least I thought I could try to keep the question on track before the usual suspects show up and have an argument about what ought to be second sourced and the politics of the countries you second source them from.

author: Pack34
author_rank: Frequent Contributor
timestamp: October 05, 2016, 03:22:02 pm
content: Quote from: Cerebus on October 05, 2016, 03:15:49 pm
second generation current-conveyor - Page 1
Forum section: electronics / projects

author: kmakaram
author_rank: Newbie
timestamp: November 14, 2012, 11:38:57 am
content: Please help me in designing a second generation current-conveyor in orcad and also give me some insight on what it is and how it works.

author: ejeffrey
author_rank: Super Contributor
timestamp: November 14, 2012, 04:56:35 pm
content: Why don't you try doing your homework first, and then ask specific questions when you run into problems?
Second life for a webcam from a laptop lid (CN-04P5V9 from DELL Precision M6500) - Page 1
Forum section: electronics / projects

author: RoGeorge
author_rank: Super Contributor
timestamp: June 30, 2019, 09:39:19 am
content: Spotted a few days ago some interesting looking wires near a dumpster bin. They proved to be the U.FL antennas' cables from the cover lid of a former laptop.Together with the antennas and the cables, there was also a PCB with a webcam and two mics on the side.Searching for the numbers from the small sticker, the camera module model, 04P5V9, was from the DELL Precision M6500 laptops, a model from around year 2010. First thought was to find the specs of the camera, so looked up for the laptop's specs, and it was a 3.2 MP camera, format 4:3, true resolution 2048x1536 pixels. Not bad.Second thought was to identify the pinout of the camera module connector. The schematic for Dell M6500 can be found online, and surprise, the webcam was in fact connected by a USB bus, so it's a USB webcam. Nice!From the schematic, the pinout can be easily identified, so it turned out the USB signals GND, D+ and D- are not only on the connector, but also on the test points near the connector.In the schematic there are two zero ohm resistors, R97 and R101, used as jumpers to set the camera Vdd to either 3.3V or 5V. I didn't know if this camera is a 3.3V or a 5V camera. Started with a 3.3V first, and slowly increased the Vdd voltage up to 5V, watching the current. Somewhere between 150-250mA. The camera was working at either +3.3V or +5V, but at 5V it got really hot after a few minutes, so I decided to put 2 diodes in series with the +5V coming from the USB cable, so the camera will see about 3.3V for its Vdd. Any other Si diodes, e.g. 1N4148, would probably work too, but just o be sure the diodes won't get hot inside the heat-shrink tube, I used two 1N4007.The webcam can do 1024x768 (or lower) at 30 FPS and higher resolutions (up to 2048x1536) at 15 FPS. Tested with Linux and Windows. No drivers required. From the USB ID it's seen as a Ricoh device.Code:~$ lsusb | grep "ID 05ca:1815"Bus 003 Device 009: ID 05ca:1815 Ricoh Co., Ltd~$ ffplay -f video4linux2 -list_formats all /dev/video0[video4linux2,v4l2 @ 0x7fb114000b80] Raw : yuyv422 : YUYV 4:2:2 : 640x480 352x288 320x240 176x144 160x120 1024x768 1280x720 1280x1024 1600x1200 1920x1080 2048x1536[video4linux2,v4l2 @ 0x7fb114000b80] Compressed: mjpeg : Motion-JPEG : 640x480 352x288 320x240 176x144 160x120 1024x768 1280x720 1280x1024 1600x1200 1920x1080 2048x1536And it works flawless!Later edit:Replaced tynipic.com broken links with local pics uploads.
Security stuff: RS485 vs 220V - Page 1
Forum section: electronics / projects

author: Ranganok
author_rank: Newbie
timestamp: June 20, 2019, 02:28:36 pm
content: Hi all,I have a question about electrical safety that I hope you can solve me.I have a rail to connect spotlights like the photo rail:Generally, 220V (L, N and PE) and DALI (DA + and DA-) circulate through this rail. I want to use the DALI connexions to transmit a MODBUS signal (over RS485 bus) to the lights, but I am concerned about the electrical safety of the controller and the lights (all consider the RS485 bus as SELV).Is there a problem? Would I have to make a galvanic separation in the controller and the spotlights? Only in the controller?Thank you

author: mbs38
author_rank: Newbie
timestamp: July 17, 2019, 12:55:14 pm
content: Hi,1. safety aside: where is your return path for the RS485 bus? You need three wires not two for that.2. separation is good enough and that is all that's needed for SELV3. BUT I would not do it, because you are laying a trap for the next person working on it...

author: Ian.M
author_rank: Super Contributor
timestamp: July 17, 2019, 01:11:13 pm
content: If the spotlights have a grounded case and the DALI bus doesn't daisy chain to any other devices (other than through the rail), then all you really need is warning stickers on the lights and the rail that the bus should be treated as mains live. (which could happen at any time if conductive debris enters the track).OTOH at the controller end, the risk of contact is significantly higher, so galvanic isolation is probably nessercery.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: July 17, 2019, 01:13:58 pm
content: You can use passive receivers (e.g. IL610) for RS485 over 2 wires, as long as you don't have many devices on the bus
Seebeck measurement tool - Page 1
Forum section: electronics / projects

author: zenman
author_rank: Newbie
timestamp: December 28, 2018, 05:25:53 am
content: I need to measure the seebeck coefficient for some research I am doing on thermomaterials but the cheapest measurement tool I can find costs $9000! Here is a link:http://en.jouleyacht.com.cn/product/20.htmlSo I have decided I will try to reverse engineer it. My plan is to combine a soldering iron, a microvolt meter, and two thermocouples connected to an ESP32 microprocessor. Then dump the measurements into a google spreadsheet and calculate the seebeck value.I plan to use:ESP32 mcuAD620MAX6675 + therocouples60watt soldering ironI am kind of guessing with my design as I have only watched someone else use a seebeck measurement tool and have never even operated one let alone know the detailed specs.It is ok if my tool is not perfectly accurate. I would be ecstatic if I can get 80-90% accuracy. That would still move my research forward. Is there anyone here that has experience with seebeck measurement tools and can offer some advice?

author: mvs
author_rank: Frequent Contributor
timestamp: December 28, 2018, 09:14:57 am
content: Quote from: zenman on December 28, 2018, 05:25:53 amYou can try to use two soldering iron tips from cartridge based soldering station as probes, like Hakko T12 or JBC C210. They have integrated heater and thermocouple.

author: zenman
author_rank: Newbie
timestamp: December 28, 2018, 01:54:57 pm
content: That’s a good thought. I was thinking about building the thermocouple in so I could output the data to a microcontroller. But maybe working the other direction is simpler and use their physical design for the housing of the thermocouple.

author: Kleinstein
author_rank: Super Contributor
timestamp: December 28, 2018, 02:02:44 pm
content: Measuring the Sebecke coefficient is rather tricky, especially measuring the actual temperature at the contact points. Much of the difficulty is likely in preparing the samples. It can be relatively easy with large samples of low thermal conductivity material, but rather tricky with brittle, high conductivity materials.The general idea would be measuring thermal EMF and temperature difference. In the simple form this could be with 3 material junctions on both sides. To form 2 thermocouples: one could be something like copper and sample and the other could be the same copper and constantan.The setup really depends on the samples - likely no one version fits all solution.

author: doktor pyta
author_rank: Frequent Contributor
timestamp: December 28, 2018, 04:03:07 pm
content: https://www.ebay.de/itm/Messplattform-fur-Seebeckeffekt-v-Fraunhofer-Institut/352183775462?hash=item51ffc9f0e6:g:sToAAOSwB-1YyYbq:rk:2:pf:1&frcectupt=true
Seeed's Open Parts Library (OPL) - Page 1
Forum section: electronics / projects

author: hamster_nz
author_rank: Super Contributor
timestamp: May 19, 2014, 12:59:10 am
content: On my doorstep today was my "Open Parts Library v2" from Seeed Studio (http://www.seeedstudio.com/depot/Open-Parts-LibraryBasic-V2-p-1560.html). It is a set of common SMD parts, and there is a matching Eagle library to go with them. Resistors, Caps, a few inductors, fuses, actives, connectors....Now that it is in front of me I'm really quite impressed, superbly packaged, well over a 1000 little bits to play with for my next design. Far better than my shoebox with little bags and partial reels that I currently have.Even if it saves me a respin of a PCB due to a device footprint missmatch it will be well worth it...

author: Dago
author_rank: Frequent Contributor
timestamp: May 19, 2014, 06:17:20 am
content: Quote from: hamster_nz on May 19, 2014, 12:59:10 amIn my opinion the best way to avoid this is to make all footprints yourself so if something goes wrong you only have yourself to blame... I personally use PCB library experthttp://www.pcblibraries.com/FPX/which outputs IPC-7351 compliant footprints for a ton of of different software packages. It makes making a footprint to take like a maximum of a minute or so.

author: hamster_nz
author_rank: Super Contributor
timestamp: July 16, 2014, 02:26:34 am
content: Sorry to dig up an old thread, but Seeed are now let you bulk-buy of single parts from the OPL to keep your OPL supplies topped up, or for small MFG runs.Prices are pretty hobbyist friendly e.g. 20xATMEGA328P-PU DIP for US$32.48 or 10x ATMEGA328P-PU 32-TQFP for $14.65.Some of the quantities are a bit high - For example what am I going to do with 50 DC power sockets? Well at under 5c each I'll just have to build more stuff!http://www.seeedstudio.com/depot/OPLopen-parts-library-catalog-c-136_138/?ref=side
Seeing samples (audio) on oscilloscope - Page 1
Forum section: electronics / projects

author: drummerdimitri
author_rank: Frequent Contributor
timestamp: April 05, 2019, 06:30:31 pm
content: Is it possible to see the sampling to determine the sampling rate of audio on a digital scope or does it have to be an analogue scope.All I see is a continuous sine wave or does the DAC fill in the blanks?

author: DaJMasta
author_rank: Super Contributor
timestamp: April 05, 2019, 09:22:45 pm
content: Not sure exactly what you're trying to see. An ADC sampling an audio signal is taking only tiny amounts of energy from the signal to make its measurement, so if you look at the signal going into the ADC (or the buffer for the ADC, depending), it should look just like the signal anywhere else, regardless of sample rate.You can probably look at the ADC's sample clock or data output and figure out what sample rate it was running, but the whole point of the ADC's input stages is to keep from altering the signal while making its measurements.If you're looking at a DAC output, a combination of filtering, interpolation, or other methods can be used to smooth out the output waveform. An oscilloscope generally has less vertical resolution than an audio DAC, so you wouldn't be able to see the steps in the output even if they weren't filtered, but every visible step on an oscilloscope is audible distortion in the signal, so there was been at least some filtering done to the DAC output to keep it from being distorted. Again, you could probably look at the data input rate or DAC clock to figure out what the sample clock was at and look at it along with the signal to try and correlate where the output would be changing, but with a (likely) 8 bit scope and a 16 bit or more audio ADC, your scope probably doesn't even have the resolution to see the DAC's minimum output step size.

author: LapTop006
author_rank: Unknown
timestamp: April 06, 2019, 06:37:37 am
content: A good explainer is available in this video:

author: drummerdimitri
author_rank: Frequent Contributor
timestamp: April 06, 2019, 07:58:06 am
content: Quote from: LapTop006 on April 06, 2019, 06:37:37 amThe video I needed thanks!

author: soldar
author_rank: Super Contributor
timestamp: April 06, 2019, 12:54:27 pm
content: Quote from: LapTop006 on April 06, 2019, 06:37:37 amThat is a really good video. Good content and well presented. Thanks!
Seeking a zerocrossing SSR without using Microcontroller! - Page 1
Forum section: electronics / projects

author: Md Mubdiul Hasan
author_rank: Regular Contributor
timestamp: November 30, 2019, 06:05:51 am
content: Hello There,Hope this post find you well.May be or may not you would love it, because this issue has reached huge number of problems.Someone could say "school project for infants".I was trying to build a SOLID STATE RELAY with zero crossing switching.Similar to this typehttp://demo5.zmpress.net/solid-state...ys-xssr-2402p2In my case I was using MOC3021[url=http://www.farnell.com/datasheets/97984.pdf]www.farnell.com/datasheets/97984.pdfand BTA100-800A.dv/dt of BTA100 is 500V/us.My application is 380V 40A load switching.Lets say for inductive and capacitive load.Main issue is "someone said me not to use any microcontroller to drive the TRIAC gate".So, random switch type SSR has been chosen,It might be non-zero crossing type SSR. 5V dc as been used that does not make sense for gate switching or its keeping the gate ON always.How about using a TIMER as follows?" alt="" class="bbc_img" />Can we control zero crossing with this idea?I think I need a zero crossing detecting circuit, what do you think? Does it possible to use this circuit for zero current/ voltage crossing?

author: Zero999
author_rank: Super Contributor
timestamp: November 30, 2019, 08:46:30 am
content: Just use the MOC3041 instead.http://exa.unne.edu.ar/ingenieria/sysistemas/public_html/Archi_pdf/HojaDatos/Optoelectronica/moc3041.pdf

author: Md Mubdiul Hasan
author_rank: Regular Contributor
timestamp: December 01, 2019, 05:19:26 am
content: Thank you very much.MOC3041 dv/dt is reasonable.The MOC3021 does not have zerocrossing The MOC3041 has the same rating of the 3021 but it has zerocrossing so does the MOC3081The MOC3081 is 800 volt peak the 3041 is 400 volt peak they both have zero crossing circuit built in.

author: Md Mubdiul Hasan
author_rank: Regular Contributor
timestamp: December 09, 2019, 01:17:45 am
content: Quote from: Zero999 on November 30, 2019, 08:46:30 amI need to be clear you few facts, my informations need to be modified.The SSR is going to switch following type of Delta capacitive bank!c_delta_load.PNG(11.87 kB. 407x308 - viewed 126 times.)It has ...R.M.S Voltage = 440 VACReactive Power, Q= 25kvrRMS Current= 32.8ACapacitor values= 342.53uFFrequency=60HzPower factor= -0.4I want to know with this higher power is there any problem with MOC308X+BTA100 resistor wattage ?For 40A application, I will change bank capacitor.
Seeking Advice on Pull-up Resistor Values for LTC4417 VALID Pins - Page 1
Forum section: electronics / projects

author: KarthiAru
author_rank: Newbie
timestamp: December 27, 2024, 01:44:03 am
content: Hello everyone!I'm currently working with the LTC4417 to manage power switching between batteries and USB in my circuit. I've noticed that the datasheet's application circuit recommends using 1M ohm pull-up resistors on the VALID pins, which seems unusually high. Does anyone have insights on why this specific value is recommended? If you've used this component, what pull-up resistor values did you choose? Any guidance or experiences shared would be greatly appreciated!

author: moffy
author_rank: Super Contributor
timestamp: December 27, 2024, 03:41:54 am
content: I would assume that the high resistor values are chosen for efficiency reasons, but would ultimately depend on the load they are driving i.e. the /valid signal.

author: KarthiAru
author_rank: Newbie
timestamp: December 27, 2024, 03:49:09 am
content: Thanks. The /valid pins are directly connected to the STM33 MCU GPIO ports in my case.
Seeking an electronic circuit that is suitable for your own hands-on production - Page 1
Forum section: electronics / projects

author: daisizhou
author_rank: Super Contributor
timestamp: May 09, 2019, 05:14:34 am
content: I hope to spend my spare time,Making interesting electronic circuits.ESR module designed by Mr. Jay_Diddy_B.Very good, very practical.I hope to get a similar circuitI hope everyone can help me.

author: daisizhou
author_rank: Super Contributor
timestamp: May 09, 2019, 03:08:30 pm
content: Hi, are you not recommended?

author: TimNJ
author_rank: Super Contributor
timestamp: May 09, 2019, 03:17:10 pm
content: I'm unsure as to what you are asking.Do you want to produce and sell something? Just want to build hobby circuits, for fun?Either way, please let us know what your interests are. Maybe we can recommend after we know what you like to work on.

author: daisizhou
author_rank: Super Contributor
timestamp: May 10, 2019, 08:50:11 am
content: Just want to build hobby circuits.I like to make interesting electronic circuits myself.I hope everyone can help me.

author: daisizhou
author_rank: Super Contributor
timestamp: May 10, 2019, 01:45:14 pm
content: Such as maintenance testing tools.Esr tester LCR testerSimple tool for repairing PCB,Circuit,New ideas......Are all of my interest

author: daisizhou
author_rank: Super Contributor
timestamp: May 14, 2019, 02:34:41 am
content: Help help,Exquisite electronic design is accepted

author: Miti
author_rank: Super Contributor
timestamp: May 14, 2019, 02:46:12 am
content: You want us to design something that you can sell? Interesting, I never thought of this...

author: daisizhou
author_rank: Super Contributor
timestamp: May 15, 2019, 12:50:40 pm
content: NO.I like electronic production.I hope to learn electronic knowledge

author: OM222O
author_rank: Frequent Contributor
timestamp: May 15, 2019, 02:57:02 pm
content: you can learn electronics pretty easily. I'm not sure how we can help since you don't have an specific question. start a project that you want to do, then ask for help when you had issues.

author: soldar
author_rank: Super Contributor
timestamp: May 15, 2019, 04:38:13 pm
content: Quote from: daisizhou on May 09, 2019, 05:14:34 amHelp you with what? Are you thinking of any specific project? Maybe this one:https://www.eevblog.com/forum/projects/5-transistor-esr-meter-design/If you are using computer language translation I am afraid it will get in the way. You might want to improve your English a bit so you can communicate better

author: daisizhou
author_rank: Super Contributor
timestamp: May 18, 2019, 02:36:48 am
content: Yes .I have seen this project.I hope to get other projects.Similar electronic ideas
Seeking Constructive Criticism on BMS Design - Page 1
Forum section: electronics / projects

author: Dowapa
author_rank: Newbie
timestamp: January 23, 2024, 05:50:53 am
content: Hello all! Before I start I want to say this is my first time posting here, so I apologize if I breach any rules or social conducts.For the past few months I've been hard at work designing the schematic for a battery management system that's going to go into a small handheld device. This is my first time designing a circuit this complicated (and this dangerous), so I've exhaustively poured over every detail of the design and have tried to learn as much as I can in the process. However, I'm aware that no matter how much attention to detail I give this design there are probably going to be things that I miss due to my lack of industry experience. I was hoping you all could take a look at this schematic and give me constructive criticism and let me know if there are any issues? I would be greatly appreciative of any advice you could send my way.Here's a little more info about this design:This is a battery management system I plan to use for a small handheld device (which contains a microcontroller, some sensors, a display, and other components). Due to the compactness of the device and sensitivity of the sensors, I elected to avoid using buck-boost voltage regulators. I needed at least 5V to play with, so I designed the circuit to protect and charge 2 18650 cells in series. I'm aware I might not have needed to include cell balancing functionality for only two cells. I decided too anyway at the request of my boss, who told me to design focused on quality and safety above all else. As far as performance requirements go I expect the circuit that this will be powering to not draw more than a few hundred mA continually, possibly up to 1 A during calculations. The jumpers are there just as a prototyping precaution (to allow me to isolate different parts of the circuit and test functionality easily). I also haven't added an output header just yet, but I plan to have pins for Pack+, Pack-, and 3V3. I'm also going to include a header for the I2C connection on the fuel gauge, and one that connects to the 2nd thermistor. My plan is to design and order the PCB for this circuit and put it through a series of tests to ensure functionality (repeated charging and discharging, fault testing, ect.)Attached is a PDF of the schematic. Each component is labeled and contains links to the specific components I selected on digikey and mouser. You'll also see my notes which contains details (mostly from the datasheets) important to the design or selection of components. I've also included a zip file containing the datasheets for the core components found in this schematic. Please feel free to nitpick any details as this is a learning experience for me.Thank you so much in advance!Edit: Make sure to open the PDF in a proper PDF viewer (like Adobe Acrobat) so you can click on components and see the comments containing the links and part# and such.
Seeking info about Siemens FZJ logic (1980's) - Page 1
Forum section: electronics / projects

author: iXod
author_rank: Frequent Contributor
timestamp: May 04, 2020, 07:24:20 pm
content: Some equipment with a "FZJ101 H4" DIP-16 IC, needs replacement. Best I can determine it's a Siemens dual JK flip-flop. No idea what logic, voltages, etc. it's based on.I'd like to find a datasheet and with the goal of replacing this IC with a modern one and some external circuitry (I think this is a high-voltage type, maybe resistant to noise?).Any help is very much welcome.Thanks.

author: fourtytwo42
author_rank: Super Contributor
timestamp: May 04, 2020, 08:18:02 pm
content: So lets try some BASIC info from you, what is the supply voltage, what is the clock frequency ? A picture of the pcb with said part also might be illuminating, sorry ost my crystal ball at the moment!

author: SeanB
author_rank: Super Contributor
timestamp: May 04, 2020, 08:24:10 pm
content: IIRC those run off 15VDC, and have quite high noise immunity. Never worked with them, just found some modules in the scrap yard.

author: amyk
author_rank: Super Contributor
timestamp: May 05, 2020, 03:52:04 am
content: https://www.eevblog.com/forum/chat/siemens-fzj-101-inforeplacement/
Seeking J-Lead SMT Leadframes - Page 1
Forum section: electronics / projects

author: envisionelec
author_rank: Frequent Contributor
timestamp: February 24, 2020, 07:30:32 pm
content: I am looking for a J-lead leadframe to install along the edge of a PCB to fit into a PLCC socket. There are lots of examples of devices like this pressure sensor (page 15) with formed J-leads soldered along the perimeter. Where can I find such an item?https://www.mouser.com/datasheet/2/18/DS-0375_Rev_A-1499152.pdf
Seeking Manual / Technical Guide for O'Neil 8i impact printer - Page 1
Forum section: electronics / projects

author: josecanuc
author_rank: Contributor
timestamp: January 12, 2020, 02:37:08 am
content: Many years ago, I was given a couple of O'Neil 8i impact (dot-matrix) printers. The plan was to develop an amateur-radio emergency communications message passing system.While that never materialized, I now have the itch to use them in some way, even if just an artistic endeavor.Unfortunately, documentation is hard to come by now. It seems O'Neil is no longer in business, and a for a while, I can see references to "O'Neil / DataMax" brand, and eventually Honeywell. Archive.org has some versions of their website that look promising, except that the actual PDF/ZIP manuals were not archived.My main interest is:Pinouts of the two data connectors: An RJ-11 jack, and a Mini-DIN 6 (female)Documentation on the serial protocol; especially model-specific escape commands for functions like form-feed, setting form height, homing, etc.So -- does anyone here happen to have a PDF of the technical manual for an O'Neil Product Development model 8i impact printer?
Seeking part # for single-pin female header connector - Page 1
Forum section: electronics / projects

author: Rasterist
author_rank: Contributor
timestamp: August 14, 2021, 08:10:29 pm
content: I know someone makes single-pin versions of the 2x3 header you see below, but I can't find any examples. Can someone point me to some part numbers (ideally, Digikey or Mouser)? Thanks.

author: wraper
author_rank: Unknown
timestamp: August 14, 2021, 08:13:31 pm
content: What you want most likely is Dupont connector, not header connector.

author: Rasterist
author_rank: Contributor
timestamp: August 14, 2021, 08:36:15 pm
content: Yup. Additional searching yielded this (https://www.amazon.com/dp/B0774NMT1S/?coliid=I39PXZD49WAP9F&colid=2CEK477UOFYV9&psc=1&ref_=lv_ov_lig_dp_it) kit, which should work fine.
Seeking Sencore LC103 Schematic - Page 1
Forum section: electronics / projects

author: Towlerar
author_rank: Contributor
timestamp: July 25, 2021, 03:06:37 pm
content: I've been searching the web for a Sencore LC103 schematic but haven't had any luck. Does anyone have it and is willing to share. Thanks!

author: coromonadalix
author_rank: Super Contributor
timestamp: July 25, 2021, 03:10:25 pm
content: http://ftb.ko4bb.com/getsimple/index.php?id=manuals&dir=06_Misc_Test_Equipment/Sencore/Sencore_LC103

author: Towlerar
author_rank: Contributor
timestamp: July 25, 2021, 05:37:37 pm
content: Quote from: coromonadalix on July 25, 2021, 03:10:25 pmThank you so much, I really appreciate it!