hybridfree/eevblog-posts huggingface dataset:
Small display module for military application usage - Page 1
Forum section: electronics / projects

author: abhishekkumar1902
author_rank: Regular Contributor
timestamp: August 24, 2018, 03:06:29 pm
content: We are working on a military radio product where we are basically looking for a small display to be used in ahot swappable remote displayfor this radio device. The display could be a small 16x2 line kinda LCD or may be a small 64x32 dots LCD or a 128x64 dots LCD but should below power consumingand should have a temperature operation range from-40C to +85CMil Temp range. Any suggestions?

author: DaJMasta
author_rank: Super Contributor
timestamp: August 24, 2018, 03:37:22 pm
content: Sounds like you want a wide temperature LCD..... they are available from major distributors and on request from LCD makers, there should be many options.

author: krho
author_rank: Regular Contributor
timestamp: August 24, 2018, 03:57:10 pm
content: If -20- +70 would suffice then take a look at JDI IOT range

author: coppercone2
author_rank: Super Contributor
timestamp: August 24, 2018, 06:50:32 pm
content: Is that a good idea for a military radio, what if the hot swap able thing gets lost in the heat of combat. Or it gets hit with concussion and the display gets dislodged in some kind of explosive attack or vehicular ramming situation, at the start of an ambush, where you really need to radio for help. Or the command camp or whatever gets attacked or overrun and you need to grab shit quickly and get out of there.I hope you have two displays on it? Maybe have the permanent display under the removable display module. And of course you can get interference that renders the radio useless.Is it like a smart watch or something?

author: abhishekkumar1902
author_rank: Regular Contributor
timestamp: August 24, 2018, 09:19:07 pm
content: Yes, that is a secondary remote display which is only required for some customers, the radio itself has a primary display unit.
Display Project - Page 1
Forum section: electronics / projects

author: Dr.No
author_rank: Newbie
timestamp: September 17, 2016, 05:56:24 pm
content: Hi!I want to realize a project, that uses a RGB TFT Display but i am an Noob with programming=Dhttp://www.mouser.com/ds/2/291/NHD-5.0-800480TF-ATXI-231021.pdfThe Display uses a 24-Bit Parallell RGB Interface (Parallel 8800) and I want to controll it with a AVR MCU but now the big question: Which one??In the End the Display just have to show a vertical and a horizontal line, so no advanced Video stuff...Can anyone give me a tip, which MCU i could use (maby one with a developmentboard and some librarys for the interface available?)greez

author: bktemp
author_rank: Super Contributor
timestamp: September 17, 2016, 06:07:49 pm
content: You can't drive the display directly using a AVR.You need to add a display controller. S1D13748, S1D13517 or SSD196x work fine for such displays:http://www.solomon-systech.com/en/product/display-system-solutions/display-controller/ssd1962/http://vdc.epson.com/index.php?option=com_docman&task=cat_view&gid=68&Itemid=Depending on how fast you want do redraw the screen a AVR might be a bit slow (800x480xRGB=1152000Bytes is a lot of data).

author: Dr.No
author_rank: Newbie
timestamp: September 19, 2016, 07:13:16 am
content: Yea! that helps a lot! Thank You-> specially, because now i found out, that the Display Pinout nearly matches with the pinout, the controller calls "MCU Interface" !! MHMM! That means, there is allready a Display Driver in my Display! nice=D
DisplayPort audio video mux - Page 1
Forum section: electronics / projects

author: VEGETA
author_rank: Super Contributor
timestamp: June 02, 2021, 08:41:44 pm
content: Hello,I have a design which has 8-lanes of VBO-HS output video up to 4k60, the IC doesn't output anything else. I needed to output it to HDMI but it requires 15k of HDCP license to get ITE ICs for it, which is a no go for me.I went for DP solution and been searching for weeks until I got the design idea correctly working using EP196E DP transmitter from Explore which does output 4k60 video on DisplayPort (may need format conversion from VBO-HS but this is doable)... but it doesn't support audio output!!So now the entire design with all sophisticated parts is hung up on mere digital audio output along with video.Therefore, do you know a way which I can mux the audio and video on DP output? I searched for ICs but couldn't find any!I am open to change the design as it needs to achieve digital video output up to 4k60 with audio... I went for DP to avoid licensing as no IC manufacturer accepts giving ICs or their documents unless I have HDMI adopter license and for ITE HDCP license (15k per year).thanks

author: viperidae
author_rank: Frequent Contributor
timestamp: June 03, 2021, 06:12:18 am
content: You either jump on the hdmi patent/copyright bandwagon or implement it yourself in an FPGA without calling it HDMI. The video signal, as far as I know is the same between Display Port and HDMI.

author: VEGETA
author_rank: Super Contributor
timestamp: June 03, 2021, 06:37:34 am
content: Quote from: viperidae on June 03, 2021, 06:12:18 amI am a noob in terms of FPGA, this project is beyond me by far.The video signal is not the same between the 2 as far as I know, there is some difference. Some passive converter cables can successfully do the conversion and some require active cables.It is really frustrating to go the entire market and never finding one IC which can do such very trivial job! imaging I got NDA of 2 big companies, one of them supplied me with their datasheet of scaler IC which is +1000 pages... this effort will be 0 without the actual audio signal capability!Right now I am trying to search for any IC which takes other forms of 4k60 video plus audio, so I can convert mine to it then output it...

author: I_Saldana
author_rank: Contributor
timestamp: June 03, 2021, 09:51:06 am
content: Some weeks ago I was looking for an alternative to the resistor ladder construction for outputing a display (vga) signal from an FPGA.This is the hdmi / DVI project/library page I bookmarked for later use:https://github.com/hdl-util/hdmi/HDMI _is_ basically DVI with audio muxed in. Except you have to pay a licence to use it - and this is important - in a commercial product. Also it has to be premade for royalties to apply, that's the loophole arduino used when not paying for hdmi on the vidor aparently.There is a whole lot of grey area. The link above talks about them in some detail.Good luck.
DisplayPort to DVI - Page 1
Forum section: electronics / projects

author: Pack34
author_rank: Frequent Contributor
timestamp: May 28, 2019, 03:09:30 pm
content: I'm looking for the cheapest way to convert a DisplayPort output to a DVI-I (single link) input. Is it really as simple as wiring in a MAX9406 (or similar) chip like the app note below?https://www.maximintegrated.com/en/app-notes/index.mvp/id/4313

author: wraper
author_rank: Unknown
timestamp: May 28, 2019, 03:20:20 pm
content: Most of displayport outputs are DP++ which means you only need a simple level shifter IC. They already can output DVI signal natively, just with different voltage level.http://www.ti.com/lit/ds/symlink/sn75dp139.pdf
Distance sensor required with 0.1mm accuracy and upto 4m range - Page 1
Forum section: electronics / projects

author: matrixofdynamism
author_rank: Regular Contributor
timestamp: May 07, 2024, 08:13:33 pm
content: For an application, I need a distance measuring sensor that has 0.1mm accuracy and no worse and can measure upto 4m easily. It will need to be incorporated into a design with a microcontroller so I can make use of the data. I have not been able to find something that matches these requirements.The table saw contains a fence and is used in woodworking. All table saws have it. I need a sensor that help me measure the distance between the sensor and the table saw fence. This is the application.Does anyone know what type of sensor I could use? Maybe you have done a project of such nature already.

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: May 07, 2024, 08:34:38 pm
content: Ultrasonic sensors have an accuracy of about 1%, so not good enough. There are LIDAR sensors used on 3D printers that do the resolution, but not the distance. I think you need an interferometric laser sensor, and that's not going to be cheap. Or, maybe a mechanical sensor based on a fine cable and rotary encoder. There was also the Trav-A-Dial used on lathes that essentially tracked a surface with a wheel-http://www.lathes.co.uk/trav-a-dial/#:~:text=An%20ingenious%20device%20%2D%20and%20widely,surfaces%20sliding%20against%20each%20other.What's your budget?

author: Retirednerd2020
author_rank: Regular Contributor
timestamp: May 07, 2024, 08:56:46 pm
content: A magnetic scale and pick-up for a DRO would do it for you if it works for you mechanically. They can be made any practical length.Have a look at dropros.com to get an idea.

author: langwadt
author_rank: Super Contributor
timestamp: May 07, 2024, 09:25:42 pm
content: https://www.sra-measurement.com/high-accuracy-magnetic-linear-tape

author: matrixofdynamism
author_rank: Regular Contributor
timestamp: May 07, 2024, 10:15:00 pm
content: You understood the predicament that I am in. If the device is expensive, what does that really mean? 1,000£?May there are prexisting solutions for this problem that are digital, that I can use.

author: Someone
author_rank: Super Contributor
timestamp: May 07, 2024, 11:09:27 pm
content: Quote from: matrixofdynamism on May 07, 2024, 10:15:00 pmYou go and talk to the suppliers:https://www.astech.de/astech/download/ldm51-lumos/Datasheet_LDM51_EN_V1.7.pdfOr do some research about how/why other machine tools all seem to use pre-packaged solutions:https://www.touchdro.com/resources/getting-started/dro-scale-selection-guide.html

author: David Hess
author_rank: Super Contributor
timestamp: May 07, 2024, 11:39:35 pm
content: Get a scale for a DRO. They come in magnetic and optical versions. The advantage of the magnetic versions is that you can cut the scale to length.
Distortion Guitar Effects Pedal. - Page 1
Forum section: electronics / projects

author: axeonic
author_rank: Contributor
timestamp: October 24, 2024, 11:53:35 pm
content: Hello,Could use some extra eyes to check my PCB design of a single transistor 2N3904 distortion circuit with selection switching of silicon and Germanium diodes. (Schematic shows all silicon diodes, but switch will select between a pair of silicon diodes and a pair of Ge diodes.)It is based on the Elektra Distortion circuit. (Q2 is just for reverse polarity protection of the voltage input). The pot and cap connected to the emitter is for gain control.Thanks for any comments/help/suggestions.Tony

author: RJSV
author_rank: Super Contributor
timestamp: October 25, 2024, 12:06:22 am
content: I would, first guess, try a typical value for potentiometer VR2, like 10k to 50 kohms.That VR2 would affect input bias, if I'm reading that schematic right.

author: moffy
author_rank: Super Contributor
timestamp: October 25, 2024, 02:16:18 am
content: If VR2 is 1k in an LTSpice sim the voltage at the collector of Q1 was 7.9V for a 12V supply, which is OK, make C7, 100u or greater as it provides an AC bypass for the rest of VR2 so that the AC, audio gain, is controlled by VR2 without upsetting the DC bias point of Q1. Values might need modifying depending on Vcc, 10k might work also.

author: antenna
author_rank: Frequent Contributor
timestamp: October 25, 2024, 02:47:31 am
content: The only distortion pedal I ever made was a crowther hotcake so I am no expert on distortion, but one thing jumps out at me from tinkering with RF.Looks like the diodes are clipping both the positive and negative peaks. With the option to control the positive and negative clipping separately, you can get different harmonic content. Symmetric distortion (like a square wave) causes odd harmonics, whereas asymmetric distortion causes even harmonics to appear.Not sure if even harmonics are wanted, but IIRC, the hotcake I built did the distortion asymmetrically.

author: floobydust
author_rank: Super Contributor
timestamp: October 25, 2024, 03:11:22 am
content: I don't think SW1 will work as you expect it, there is always the 4 diodes in parallel seen.Because U1/U4 output also goes to U3/U5 via R3. Germanium diodes will always clamp before silicon due to their lower forward voltage.

author: axeonic
author_rank: Contributor
timestamp: October 25, 2024, 03:13:04 am
content: Thank you. I'll experiment with those values you mention.TonyAm

author: axeonic
author_rank: Contributor
timestamp: October 25, 2024, 03:15:16 am
content: Quote from: floobydust on October 25, 2024, 03:11:22 amYeah, I have to think more about how I have those clipping diodes wired. Thank you.
Distribute 12V on DIN Rail? - Page 1
Forum section: electronics / projects

author: Lord of nothing
author_rank: Super Contributor
timestamp: June 04, 2024, 05:26:44 pm
content: HiI have multiple Pc Fans in my Server Rack and I got an 12V Power Supply is there some easy way to distribute the 12V from the Power Supply via my DIN Rail?Thanks

author: ajb
author_rank: Super Contributor
timestamp: June 04, 2024, 06:19:39 pm
content: Sure, just searching for 'DIN rail terminal block' should turn up lots of options. I like this spring contact style, they allow ferrule-terminated wires to be pushed directly into the terminal and have a small pushbutton to release, which makes them very easy to use:https://www.altechcorp.com/CP/There are plenty of other options, though, from major manufacturers as well as cheap clones, so take your pick. Generally you stack as many terminals as you need next to each other, and then insert jumper strips to electrically connect adjacent terminals as needed.For power distribution, double level terminals that allow both levels to be jumpered independently work very well. You can use one level for positive and the other for negative, and land the each pair of fan wires at the top and bottom positions on a single terminal. I used them to wire up 24VAC zone valves for my heating system, photo attached. You can see that there is a continuous jumper (orange strip) on the lower level to join all of the neutral/common connections together, and three separate jumpers on the top level to join the live connections into three separate zone groups. Single-level blocks would require each load to connect to two different groups of terminals, so this keeps the wiring much tidier.
Distributed load loudspeakers ? - Page 1
Forum section: electronics / projects

author: chris_leyson
author_rank: Super Contributor
timestamp: September 26, 2018, 01:14:25 am
content: I stumbled across a youtube video from "tech ingedients". Fantastic diy speakers for $30...Somewhere he says to get the best bass response you want to make the planar diaphrams as large as possible, which he does.Get a teeny tiny loudspeaker from Dayton audio, DAEX25FHE-4, and stick it on to back of a really huge diaphram for better bass response, and this is shown in the video linked below at 10:18. The driver is just stuck on with a bit 3M tape so at low frequencies you have to rely on the mass of the driver to produce any sort of force in the diaphram. What do you think they put the mounting holes in the driver for, to make look pretty or something, they are there for a reason. Some expensive Canadian wood which I didn't catch the name off sounds better though, less tinny.Reonance in rigid plates gets a mention, use the "magic" 2/3 or 5/3 offset and maybe a bit of damping , no magic there really. The whole video is a good example of bad physics and bad science. No swept frequency measurements whatsoever and no comparison with a reference speaker. The guy is doing a video on "fantastic diy speakers" but can't can't even get the sound recording right, is he for real or just taking the piss.

author: BravoV
author_rank: Super Contributor
timestamp: September 26, 2018, 02:16:54 am
content: Quote from: chris_leyson on September 26, 2018, 01:14:25 amThese days, as long you can shoot your own video and upload it to be viewed publicly, you can claim yourself what ever you like.

author: oPossum
author_rank: Super Contributor
timestamp: September 26, 2018, 02:38:11 am
content: Quote from: chris_leyson on September 26, 2018, 01:14:25 amFrequency measurement begins at 15:04https://youtu.be/CKIye4RZ-5k?t=906

author: Gyro
author_rank: Super Contributor
timestamp: September 26, 2018, 08:32:46 am
content: NXT developed and patented these distributedmodepanel speakers years ago. They marketed transducers and complete panels for wall mounting and flat panel displays. That's probably the 'inspiration' for his video, there was quite a fuss about them at the time...https://en.wikipedia.org/wiki/Distributed_mode_loudspeakerEDIT: You can still find them on ebay in fact:https://www.ebay.co.uk/sch/i.html?_odkw=NXT+speaker&_osacat=0&_from=R40&_trksid=m570.l1313&_nkw=NXT+flat+speaker&_sacat=0
Distribution of a 28.8mhz clock to 4 circuits - Page 1
Forum section: electronics / projects

author: kushagrad28
author_rank: Newbie
timestamp: March 19, 2017, 07:28:55 am
content: Hello This is Kushagra from India. I am currently working on a project to time synchronize multiple RTL-SDR's. For capture frequency hopping GSM. I have read that connecting the output of a single TCXO to multiple dongles only works up to 3 dongles due to increased inductance of the circuit. I need to have at least 4 to be time synchronized for my project. How do I do that. I am currently a student of Electronics 2nd year. I tried to figure it out online. most of the circuits use fan out clock buffers. and I don't have much experience working with them.So I am looking for a way to get 4 outputs from a single output of a clock to feed to my clock input of different dongles. Any help would be greatly appreciated.P.S. Sorry for my confusing manner of writing.

author: kushagrad28
author_rank: Newbie
timestamp: March 19, 2017, 08:40:33 am
content: Very helpfull !! Thank YouWill try to make this.
Diversion of power flow using toggle switch - Page 1
Forum section: electronics / projects

author: Gowda1
author_rank: Contributor
timestamp: December 11, 2020, 11:46:47 am
content: Hey,I want to divert the power flow between two lines as shown in the figure.My question is, Is it possible to divert the power flow just using toggle switch? Because I am not going to switch between the lines when it is operating. I only switch it when the circuit is off. I am going to do it on PCB. Do I have to worry about any ratings? I thought of using relays but anyways it takes lot of space and also as I said I am not going to do the switch it when the system is working. Please let me know if its possible or not. If its possible what are the factors I should worry about. Thanks.

author: opampsmoker
author_rank: Regular Contributor
timestamp: December 11, 2020, 02:06:56 pm
content: if you can be absolutely certain there is no current flow (not even temporary capacitor charging current) when you close the switchs, then you dont have to worry about the voltage rating of the switch. But you have to worry about the current rating of the switch.400VDC is highly dangerous and i believe you know this.
Diversity Antenna Switch IC or Board Wanted - Page 1
Forum section: electronics / projects

author: ocw
author_rank: Regular Contributor
timestamp: September 07, 2021, 11:48:57 pm
content: What IC's or boards are available for automatic selection of the better receive antenna? This is for the 500 - 600 MHz range. I am not finding much available. While it would be better to have the selection based on SNR, I can supply a voltage based on the signal strengths.

author: ocw
author_rank: Regular Contributor
timestamp: September 08, 2021, 03:15:44 am
content: It looks like it comes down to my simple idea which amounts to the two receiver method. Use two narrow pass band filters having less bandwidth than the desired signal has (which I already have) feeding two detectors. The antenna selected is determined by the stronger of the two voltages from the detectors. If any noise difference stays the same, that difference (if there is any) could be removed by a balancing control.As said, it would be better to have the selection controlled by SNR, but that raises the complexity to a point that I am trying to avoid.
DIvider ladder for constand dB steps - Page 1
Forum section: electronics / projects

author: Barry Hardhouse
author_rank: Contributor
timestamp: October 01, 2023, 09:08:16 am
content: Hi All.I've had occasion a few times to use this kind of ladder attenuator, which gives constant-dB steps. This network is basically a general case of the R-2R ladder we see used for D/A conversion. Moving towards the centre of the ladder, and assuming that the ladder is "long" enough, the output impedance asymptotes to a constant value.I don't think I've ever seen it treated in a textbook, so I thought I would formalise the design equations and share it here in the hopes it might be useful.Mods, feel free to move if in an inappropriate location.EDIT:...aaaaand, yes! There's a typo in my thread title.

author: MathWizard
author_rank: Super Contributor
timestamp: October 10, 2023, 11:14:22 am
content: I saw an old parts a while back and it had lots of attenuation boxes, and filters, all in big sturdy cases with big switches, etc. I bet they lasted a long time. I made a standard 6 digit resistance box, it would be nice to have a few other types, like a dB stepper box or whatever it's called.
dividing 100 MHz, should I expect technical difficulties? - Page 1
Forum section: electronics / projects

author: SArepairman
author_rank: Frequent Contributor
timestamp: April 29, 2014, 08:01:30 pm
content: I need to divide the output of a DDS square wave output (100 MHz) , using a hittite microwave part. I never have done anything at these frequencies.Is there anything special that I should know about doing this? Everything else on the board is low frequency and there is a ground plane. I intend to put the divider chip as close as possible to the dds chip. I need this so I can really tune the ever living crap out of frequency. But I am kind of scared of 100 MHz. The 100MHz output channel of the dds chip has a different power supply then the other lower frequency outputs.

author: mathias
author_rank: Regular Contributor
timestamp: April 30, 2014, 01:35:11 pm
content: 100 MHz is not that tricky, but I guess it depends on the power levels you are using and possibly the impedances involved. I assume everything is 50 Ohm?Anyway, Hittite parts for 100MHz sounds like extreme overkill. A comparator (MAX961, AD8611, ...) and some high speed cmos (74AC74 divide-by-two) will get the job done.

author: SArepairman
author_rank: Frequent Contributor
timestamp: April 30, 2014, 03:06:47 pm
content: Quote from: mathias on April 30, 2014, 01:35:11 pmthe free parts box inspires some interesting design choicesyes, it is all 50 ohms.

author: c4757p
author_rank: Super Contributor
timestamp: April 30, 2014, 03:10:49 pm
content: Quote from: SArepairman on April 30, 2014, 03:06:47 pmSave them for something more interesting! You could do this with a small handful of junk parts...
Dividing sensor network into multiple connections - Page 1
Forum section: electronics / projects

author: mrburnzie
author_rank: Regular Contributor
timestamp: July 09, 2020, 04:19:59 pm
content: Hi everybody,I have a project where I have parking sensors on the streets. The streets are very dense and full of traffic.For now I'm using LoRaWAN to communicate with all the sensors. The gateways are on top of buildings.My requirement is to have a stable network that is of course also low power (>10 yrs). Till now the gateway price and position was always a negative thing when it comes to the LoRaWAN system, especially talking parking sensors. My idea is to divide the connections into two parts.The first part would be to change the sensors RF IC/module into something more generic (something like:https://datasheet.octopart.com/ADF7024BCPZ-Analog-Devices-datasheet-27843825.pdf) and the second part would be to create small gateways that are battery powered. The gateways would have the same RF IC/modules and an NB-Iot device that sends the data to the server (API).What are the thoughts on this?Also I found haystack, that mentions a lot of issues with LoRaWAN:https://medium.com/@patburns/announcing-haystacks-lorawan-replacement-program-1a72cb4cf201andthat is one of the reasons I want to skip LoRaWAN if possible. It is a great protocol (I don't want to offend the LoRaWAN fanboys), but I want to look at other solutions too.
DIY 132-Ball csBGA? - Page 1
Forum section: electronics / projects

author: NivagSwerdna
author_rank: Super Contributor
timestamp: May 24, 2018, 11:06:18 am
content: Is it feasible for a hobbyist to hot air on a small-ish BGA? What are the pit falls?I'm potentially looking at a LCMXO3LF-4300E-5UWG81CTR50 or similiar.Or is this unrealistic and should be left to the professionals?Is verification via JTAG possible?

author: NivagSwerdna
author_rank: Super Contributor
timestamp: May 24, 2018, 11:11:09 am
content: Just foundhttps://www.eevblog.com/forum/projects/bga-for-hobbyists-is-it-even-possible/looks like this has been well discussed in the past. Thanks!
DIY 18650 Lithium Battery Charge, Protect, Boost to 5V Circuit - Page 1
Forum section: electronics / projects

author: dusnoki
author_rank: Newbie
timestamp: April 12, 2018, 10:06:00 am
content: Hez guys, new video is finallz up. I created a DIY 18650 Lithium Battery Charge, Protect, Boost to 5V Circuit. It can charge the battery using a micro usb cable, protect it from overdischarge, and boost the voltage to 5v.It wasn't easy as I'm a web developer by profession and only meddle in electronics on a hobby level, and have learned anything electronics related from youtube videosI've read a lot of datasheets and used SMD components so the board would be the smallest possible. It isn't as small as I would like but for my first try it's not too bad. Main thing is that it worksYou can check out the video atI'll just leave you with a couple of pictures of the board and schematic.Hope you like the video
DIY 3D Printed Atomic Force Microscope  - Page 1
Forum section: electronics / projects

author: diracshore
author_rank: Regular Contributor
timestamp: February 21, 2012, 11:58:54 pm
content: Check this out,http://www.nanowerk.com/spotlight/spotid=2304.phphttp://namcub.accela-labs.com/pdf/Print%20your%20atomic%20force%20microscope.pdfFull design here,http://web.archive.org/web/20080106164837/http://www.biophysik.physik.uni-muenchen.de/PlasticAFM/Original thread,http://groups.google.com/group/openmanufacturing/browse_thread/thread/e3ea9182fe618a71

author: Unknown
author_rank: Unknown
timestamp: February 22, 2012, 09:49:53 pm
content: I'm impressed by the performance they get from the printed head, I would never have expected this to work. Too bad you can't print all of the other equipment.
DIY 4-Arm Helping Hands Solder Tool  - Page 1
Forum section: electronics / projects

author: TorqueRanger
author_rank: Frequent Contributor
timestamp: October 08, 2012, 06:53:13 pm
content: I found this awhile ago and thought you guys would like this ... I not any part of the sale of the of product if you choose to purchase one from him..This is a quick DIY post on how to make a 4-arm helping hands solder tool. This tool is extremely helpful for holding wires, connectors, boards, or anything else that you typically solder together. The arms are easy to move, and they stay put during intricate soldering tasks. I use mine every time that I solder and it makes this job MUCH easier and more fun!http://fpvlab.com/forums/showthread.php?5406-DIY-4-Arm-Helping-Hands-Solder-Tool

author: Mediarocker
author_rank: Contributor
timestamp: October 08, 2012, 07:01:25 pm
content: That is pretty neat! I also like the coloring.Hmmm.. Yet something else to spend my money building

author: metalphreak
author_rank: Frequent Contributor
timestamp: October 09, 2012, 06:51:57 am
content: Interesting use for coolant pipes and nozzlesThey're typically used on milling machines, cold saws, and other cutting tools to spray a stream of coolant on the material you are cutting.Much cheaper and easier to get from China/Hong Kong off ebay if you aren't in the USA.For example:http://www.ebay.com.au/itm/32cm-Long-16mm-Thread-Round-Nozzle-Water-Oil-Coolant-Pipe-/190734651527?pt=AU_Business_Industrial_Industrial_Supply_MRO&hash=item2c68abd087#ht_2573wt_1156

author: jeremy
author_rank: Super Contributor
timestamp: October 09, 2012, 11:16:41 am
content: Just bought some arms off ebay, see how it goes.

author: T4P
author_rank: Super Contributor
timestamp: October 09, 2012, 11:18:46 am
content: Seems interesting, they only cost 0.80USD in chinaDefinitely giving it a try ... i hate my "helping hand" so much

author: ablacon64
author_rank: Frequent Contributor
timestamp: October 09, 2012, 12:50:50 pm
content: That's an interesting project. I've seen some on instructables also but never tried them. I looked for those pipes in Brazil but couldn't find any.
DIY 4 wire Kelvin leads - Page 1
Forum section: electronics / projects

author: drummerdimitri
author_rank: Frequent Contributor
timestamp: August 17, 2019, 04:36:20 pm
content: I'd like to make the best leads to benefit from the 4 wire resistance measurement capability of my DMM6500 however, I need some pointers on how to make the best ones possible.Firstly, what gauge silicone wire should they be? I need them to be between 1 and 1.5 m long.I got these connectors which have separate connection points so I can wire two cables to each connector:https://www.aliexpress.com/item/32570109938.html?spm=a2g0s.12269583.0.0.9b9d33b004dabaWill be terminating them with gold plated banana plugs.Anything else I should be concerned about?

author: Fire Doger
author_rank: Regular Contributor
timestamp: August 17, 2019, 04:54:08 pm
content: "Best Leads" and aliexpress doesn't match.These are not goldplated, they are gold painted.Also I am sure there will be special wires for this purpose, depends how expensive you want to go.

author: MosherIV
author_rank: Super Contributor
timestamp: August 17, 2019, 06:18:26 pm
content: HiYes, I got similar clampshttps://www.eevblog.com/forum/testgear/gold-plated-test-probes-any-good/25/No, they are not the best but they work.Do not worry, the gold plating is ok and so far has not flaked off.You will actually limited by what will fit through the hole of the clamp housing.I used a small uk based firm, they only supply 1 type of silicone test cable. So I just got that.Everything they supply is good quality so I do not have to worry.Think about strain relief. I put cable ties on my cables so the the cable tie is against the hole in the housing.I used mine at work this week. Managed to measure 55 micro

author: drummerdimitri
author_rank: Frequent Contributor
timestamp: August 17, 2019, 11:06:36 pm
content: Initially, I soldered the cable to the bottom of the connector as it was intended since they had already placed a blob of solder there but then I realized I could solder way up right next to the points of contact which would help lower the lead's resistance by a bit and provide strain relief as the cables are held down tight by the springsAll I need to do now is find a way to hold the cables in place. It's a shame there isnt any screwable piece of plastic to keep it held in place.I'd rather not use heat-shrink as it is not an elegant solution so maybe some hot-glue would do the trick?

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: August 17, 2019, 11:31:54 pm
content: The nice thing about a 4-lead measurement is the leads don't matter much. Anything that pleases you is probably plenty good. I have a friend who makes them out of plastic clothes pins and copper tape!

author: MosherIV
author_rank: Super Contributor
timestamp: August 17, 2019, 11:41:35 pm
content: Nice idea soldering nearer to the tips.As I mentioned, I used a cable tie as strain releif. See pictures.I also used some heat shrink to bundle the cables together to stop them becoming a tangled mess.I see you used the spring to hold the cable and the cable insulation also stops the spring shorting the 2 halves of the clamps, nice
DIY 4wire probes/Kelvin clamps - Page 1
Forum section: electronics / projects

author: MosherIV
author_rank: Super Contributor
timestamp: June 30, 2017, 07:57:46 pm
content: Hi, so I bought these cheap clamp probes ages ago (Aug2016) and have only just got round to wiring them up. For anyone who wants to know the tricks to making them.I got them from Amazon :https://www.amazon.co.uk/gp/product/B00XOL4332/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1I got the cheapest ones I cound find on Amazon, yes I know I can get them cheaper on ebay, banggood etc but I prefer the protection and customer service from Amazon.They come with no instructions, so you have to figure out what to do yourself.First, take them apart by removing the spring.Then lift and slide out each prong.Solder a wire to each prong :Be careful not to let solder overflow down the side of the prong, they fit tight in the plastic shell and solder will stop them fitting.

author: MosherIV
author_rank: Super Contributor
timestamp: June 30, 2017, 08:00:38 pm
content: Next insert one prong into the shell :Feed the wire through the hole in the shell :I added a cable tie for strain releifDo the same on the other side.

author: MosherIV
author_rank: Super Contributor
timestamp: June 30, 2017, 08:12:02 pm
content: Now the really trick part - putting the spring back in!Sorry, I did not take any pictures of putting the spring back in but I needed both hands and them some to do itMake sure the short side of the spring is on the insulated probe (the insulation stops the spring acting as a short between both prongs)I found the easiest technique to be pushing the spring in until the long spring rests on the wire.Then use something like a screw driver to lift the short spring (do not let it drag on the insulation on the prong - it will drag and lift it). Use screw driver as a slide for the spring, use your finger and push the centre of the spring and the short arm will just slide along the screw driver blade.When the spring loop is in line with the shell pivot, it is on place. Carefully lift and slide the screw driver out.(Sorry - forgot to take a picture of the black one at this point)

author: MosherIV
author_rank: Super Contributor
timestamp: June 30, 2017, 08:16:34 pm
content: Finally, I used some heat shrink to hold the wires together and make it look neat :I used them on my Schlumberger 7155Plus which has 4wire resistance measurement :This is it measuring a 0.1Had to null out the probes to get an accurate masurement on this low a reading
DIY 500x High Voltage Passive Oscilloscope Probe - Page 1
Forum section: electronics / projects

author: leblanc
author_rank: Regular Contributor
timestamp: August 09, 2017, 07:36:47 pm
content: ** I will not responsible for any injuries or for any damage this may cause to your equipment. Use the following design at your own risk and use caution when dealing with high voltages! Always review your connections before applying power to the system. **I needed to measure high voltage (a few kV) with an oscilloscope; we only had standard 10x passive probes (and some other low voltage active probes). Instead of spending a few thousand dollars on a high voltage probe, I built my own 500x (500:1 attenuation) high voltage passive oscilloscope probe for about 25USD. It's really easy to build. I thought I'd share the design.I didn't care really care about AC performance above a few hundred Hertz, so I omitted the probe tip capacitor and the adjustable compensation capacitor. This design can certainly be improved upon.Diagram (I also printed this and taped it to the probe):Place high voltage resistor and coax cable on a piece of perfboard (make sure you get the kind with no pads or plating, otherwise there will be far less creepage).Solder on the resistor, coaxial cable, and mini-grabbers. Apply a generous amount of hot glue to reduce stress on solder joints. If you want, you can conformally coat the board. Cut the perfboard to size. I find tin snips usually work well on FR4, but the perfboard I got was particularly brittle, so I just scored it with a knife and broke it with my hands.Place heatshrink and apply label. Depending on your heatshrink diameter, you may want to do this before attaching the minigrabbers.BOM:1x coax cable (TPI 58-072-1M), cut in half, I used one to make two probes1x 500M high voltage resistor (Ohmite SM108035006FE)1x perfboard (i.e. Keystone 3396), with no pads or plating2x minigrabbers (i.e. Pomona 4176-02, this is a pair of black+red)A few inches of high voltage wire, i used some 22AWG high voltage wire we had in the labA few inches of high voltage heatshrink, large diameterUsage:Your oscilloscope channel should be configured in 1Mohm mode (like you would set it for an ordinary 10x passive probe), not in 50ohm mode. If your oscilloscope allows, you set the gain to 500x (actually 501x would be more accurate, since we have a voltage divider of 500Mohm with the scope's internal 1Mohm). If you don't have the option to set this, just remember to mentally scale your measurements (i.e. multiply by 50 if your setting is 10x).The mini-grabbers are obviously not rated for high voltages; treat them as live conductors when the system is powered.Do not touch the high voltage side of the probe when the system is powered. Instead, secure the probe clips with the system powered off, then turn on the power.Keep in mind that the ground clip on passive oscilloscope probes is connected to earth ground.
DIY 8-bit computer - Page 1
Forum section: electronics / projects

author: Noah1989
author_rank: Newbie
timestamp: April 10, 2014, 05:46:37 pm
content: Hi,here's a project that I've in fact been working on for a long time now: an 8-bit computer based on the Zilog eZ80F91AZA microcontroller. I am currently building a second prototype and decided to document all the steps along the way. I thought you might find this interesting:https://www.youtube.com/playlist?list=PLpsoj9xEaVLdEZXYoIKRCeHpG_DMm27ABI am planning on making this a proper DIY kit, the ultimate goal is an easily accessible, fully hackable 8-bit computer, that works with modern hardware, i.e. USB peripherals and DVI video. Definitely a mailbag item, when I have some samples ready!All open source of course, anything else would defeat its purpose:https://github.com/Noah1989/EightZero/tree/zinu/src

author: CaptnYellowShirt
author_rank: Frequent Contributor
timestamp: April 10, 2014, 07:59:07 pm
content: I remember writing ASM for my TI-82 Z80 way back in the day. I can't imagine the patience it takes to build this kind of thing from scratch. My hat's off to you.

author: calexanian
author_rank: Super Contributor
timestamp: April 10, 2014, 08:25:38 pm
content: Looks great. You have a good German accent too. makes it even more entertaining. I did not watch your previous videos. What clock speed is it running at? Also what speed in the serial RS232 data running at?

author: Noah1989
author_rank: Newbie
timestamp: April 10, 2014, 10:03:02 pm
content: Quote from: calexanian on April 10, 2014, 08:25:38 pmThe clock speed it 4MHz, but can be multiplied by an on-chip PLL to up to 48 MHz (50 is the specified max the chip can do, but when I selected the crystal I somehow thought 50 was dividable by 4.. stupid me) I will probably use 2 or 5 MHz when I turn this into a product. The idea is to keep speed low so that you can hack around with external circuits on a breadboard, but optionally increase speed using the PLL if you need more processing power.Serial runs at standard 9600 Baud, 8 data bits, no parity, 1 stop bit
DIY 948-type desoldering station - Page 1
Forum section: electronics / projects

author: bogdan2014
author_rank: Regular Contributor
timestamp: April 20, 2023, 09:59:10 am
content: I thought it would be a nice project to build a vacuum desoldering station (similar to 948 types). I got the gun and a vacuum pump and I'm now onto implementing the control circuit, especially the temperature control.The maximum temperature I got at the tip was around 450C, which is too much, I'd like to keep it somewhere in the range of 300-350C.I measured the voltage coming from the thermocouple (assuming K-type) at different tip temperatures and noticed a few things:- there's differences between readings (always starting with a cold tip and observing the voltages at different temperatures); probably due to the thermocouple not being compensated- there's quite a lot of thermal mass, even after cutting the supply the temperature rises by another 20-30 degrees- consequently, there's a difference between the voltage reading and the temperature reading (for example, the voltage starts to go down even though the temperature is still high)So I'd like to start from here and do a correct reading of the temperature. I already ordered a MAX6675 compensator IC and I'll see what I get from that.

author: ralphrmartin
author_rank: Frequent Contributor
timestamp: July 24, 2023, 05:42:38 pm
content: I'm about to do a project which needs similar suction to a desoldering gun. Can I ask which vacuum pump you used?

author: tooki
author_rank: Super Contributor
timestamp: July 24, 2023, 05:56:53 pm
content: FWIW, Pace (which makes excellent desoldering tools) uses a 12V DC, roughly 20inHg/70mbar vacuum pump, which they then overdrive at 24V for around 1/2 second before dropping down to 12V. That gives an initial burst of higher vacuum to clear the hole.If you decide to emulate that behavior, then you want to get a pump with a brushed DC motor, not one with a brushless DC motor, since the overvoltage would likely just fry the controller. (Just don’t try to sell anything using that approach, since they patented it.)Here’s a video I took of it in slow-mo, by the way:
DIY AC power monitoring - Page 1
Forum section: electronics / projects

author: John B
author_rank: Frequent Contributor
timestamp: January 31, 2025, 12:14:08 am
content: I'm mulling over making my own mains power monitor which will output data over WIFI using MQTT.I don't mind DIY'ing the interconnectivity, but don't have any real urge to reinvent the wheel in terms of the actual data sampling and calculations.I can manage the isolation side of things, meaning measuring current via current transformers and probably a small step down transformer to provide the voltage waveform.The question is whether there are any modules which take (low) voltage and current waveforms and calculate real, reactive and apparent power, current, voltage etc. Then output data by SPI or I2C etcI've used a few consumer items like these, the features level of accuracy is fine for me. This design is obviously mass produced for many markets. I think from opening up one previously it's all a monolithic ASIC blob, but something along these lines in terms of functionality would be desireable.https://www.amazon.com/YICHENG-Electrical-Overload-Protection-Backlight/dp/B0CDPQ4CXW/ref=sr_1_64?sr=8-64&xpid=Gsiy1Ht0I7L47https://www.amazon.com/Electricity-Electrical-Consumption-Backlight-Protection/dp/B09BQNYMMM/ref=sr_1_6?sr=8-6

author: scottapotamas
author_rank: Regular Contributor
timestamp: January 31, 2025, 12:56:32 am
content: I don't have great documentation for it unfortunately, but I've been running a ATM90e36 based 3-phase monitor on my home since 2019 (~6yrs) with no complaints.A CT and 12V transformer per phase and I've measured it to ~watt accuracy. I log phase voltage/currents as well as power-factor and frequency, if you wanted complex power values they're available too.https://www.tindie.com/products/whatnick/atm90e36-devkit/is what I used to finish the hardware side quickly, seems like he has a single-phase breakout available too.

author: ledtester
author_rank: Super Contributor
timestamp: January 31, 2025, 01:10:00 am
content: There are AC power meters which can talk RS485, e.g.:https://www.aliexpress.us/item/3256804134979756.html
DIY AC Voltage reference - Page 1
Forum section: electronics / projects

author: krish2487
author_rank: Frequent Contributor
timestamp: May 07, 2012, 07:00:43 pm
content: Hello..I have a fluke 111 TRMS that i would like to calibrate(It is fairly accurate even now as when compared against a new calibrated Rish 16S True RMS (rebranded gossen metrawatt).it is off only in the decimal readings. i wanted to perform a at home calibration to see if1) I could "tune up" the fluke to perform as well as the Rish2) If i could develop a fairly accurate reference for resistances/voltages/currents at the lowest cost possible to get a 0.1 % or thereabouts standard.The semiconductors available seem as a pretty good compromise considering a true calibration from a government body would cost more than my annual salary so would getting a Reference itself off ebay.Passives in 0.05% tolerance range are about 4 times the cost of a 1% tolerance passive.Throw in a bunch of Ics and resistances and caps and inductances. It is by no means negligible cost but still a LOT cheaper than getting it calibrated by a Institution ( which i feel is not required for hobby purpose).I got my hands on the service/calibration manual and saw that the calibration itself was done at 6V,6A etc, you get the point right.So getting a DC voltage reference, capacitors, resistors, inductors seems pretty straightforward.I am stumped at a 6V RMS AC reference which is holding me back at the moment. I have no clue as to how to generate a 6V AC RMS referenceSo I request all the guys present on this forum to help me with this roadblock. Maybe we can come up with a solution that might be a poor-mans reference calibration, much like the uCurrent.Or putting it another waySo i sound as if I am talking out of my head or is there a geniune need for such a thing??I figured not everybody can afford a bench reference (even used).

author: Jeff1946
author_rank: Regular Contributor
timestamp: May 07, 2012, 08:25:33 pm
content: One way. Connect a suitable AC source (Wall wart or whatever) to a power resistor. Connect your meter parallel to the resistor. Place the resistor into an insulated container (coffee mug?) with water and a temperature probe. Gentlely stir and accurately measure time for the change between two temperatures. Repeat with a known DC voltage similar to the RMS of your AC voltage. Ratio of the time between the same two temperatures should be the inverse of the ratios of the square of the voltages. I would expect this would be about 1% accurate if you are careful. Thus an accurate value of the resistor or accurate temperatures doesn't matter as they are the same for both experiments. Note you must coat any bare wires so you don't electrolyze the water. Note this measures RMS of the AC. It is a little tricky because home AC is often a little distorted due to non-resistive loading. For example note the current rating printed on a compact fluorescent lamp is greater than you would calculate from the power rating.Another way. Measure peak to peak voltage on an oscilloscope and compare to known DC voltage. Again at best 1% accurate.