hybridfree/eevblog-posts huggingface dataset:
Yet another high speed pulse generator (LMG1020) - Page 1
Forum section: electronics / projects

author: JohnG
author_rank: Frequent Contributor
timestamp: October 08, 2018, 07:50:56 pm
content: It won't win points for the fastest, but it will drive 50 ohms to 5V, and probably 10 ohms (have not had a chance to test), in a few hundred ps:http://www.ti.com/product/LMG1020Here are some pictures with an RTO1024 (spec'd at 175 ps risetime). Yes, I know there is some ringing.Not a bad little chip. And no, I don't work for TI...John

author: awallin
author_rank: Frequent Contributor
timestamp: October 09, 2018, 04:27:19 am
content: Looks interesting. For a pulse-distribution amp I am using IDT5PB1108 where 5 outputs are connected in parallell. Each output on the chip is 50R terminated, so the 5 parallell outputs drive about 2.7V into a 50R load - with decent rise-time (~400ps IIRC) - with the drawback that the output isn't 50R matched.This chip might be a good alternative if higher voltage levels are required?Would be nice to see a comparison between the LMG and the IDT on the same scope..https://www.ohwr.org/projects/pda-8ch-fda-8ch/wiki/wiki
Yet another home automation project, for fun. And other stuff. - Page 1
Forum section: electronics / projects

author: Kwincks
author_rank: Newbie
timestamp: August 19, 2015, 02:03:38 am
content: Hey Everyone!here is a long term project to make electronics stuff do stuff in my unit. and other interesting things ive done.The project uses Atmel mega1284 and Wiznet820io (W5200).And there is also a quickie USB keyboard emulator project, i was bored in the holidays.https://arrrhell.wordpress.com/(Scroll down a bit on the site to see stuff eh.)Simple Demohttps://youtu.be/gksnTD6b7lY

author: ledfreak3d
author_rank: Newbie
timestamp: August 19, 2015, 05:22:40 am
content: Looks very nice great work
Yet another identify this chip - Page 1
Forum section: electronics / projects

author: PaulAm
author_rank: Frequent Contributor
timestamp: June 26, 2021, 08:56:56 pm
content: I'm cleaning up my desk and found a tube of 4mm QFN-28 ICs that I cannot identify. Any searches I've run come up with nothing.There is no manufacturer's mark on them, just 3 lines:9788ET1909BJDRI believe that is a numeral 1, but might be an L or an I.The center of the bottom of the chip has a heatsink area.Anyone have a clue?

author: mariush
author_rank: Super Contributor
timestamp: June 26, 2021, 09:08:01 pm
content: MAX9788 / MAX9788ETI ?datasheet:https://datasheets.maximintegrated.com/en/ds/MAX9788.pdf

author: PaulAm
author_rank: Frequent Contributor
timestamp: June 27, 2021, 12:04:54 am
content: And give that person a prize!Yep, that was it.thanks!
Yet another identify this component thread... - Page 1
Forum section: electronics / projects

author: GadgetBoy
author_rank: Regular Contributor
timestamp: March 03, 2019, 09:06:52 am
content: This board is from a little UVC LED water sterilizer I got on ebay. Trying to identify this little SOT-23 package, which I think might be a voltage regulator. Transistor doesn't make sense, and I'm having trouble making out the tracks vecause of the super shiny white coating on the board. All I can identify is that the code on the chip is 1A40 (I think).Also, any thoughts on why R1 isn't populated and the positive lead is bodged on?P.s. Sorry for the B&W pic, but it made for much better contrast for identifying the letters on the chip.

author: RES
author_rank: Regular Contributor
timestamp: March 03, 2019, 09:18:41 am
content: http://www.s-manuals.com/smd/1a(1A40 sot-23)MT501 (mos-tech)https://usermanual.wiki/Document/mt501mostech.16022346/help

author: GadgetBoy
author_rank: Regular Contributor
timestamp: March 03, 2019, 07:18:44 pm
content: Wow you guys are great! Thanks!Also, what an adorable little LED driver! Didn't know they came that small.
Yet another IN-14 Nixie Clock, advice needed - Page 1
Forum section: electronics / projects

author: neontec75
author_rank: Newbie
timestamp: June 17, 2020, 01:12:33 pm
content: Hello!I've designed a simple Nixie Clock shield:https://github.com/NEONTEC75/4IN14NixieShieldhttps://github.com/NEONTEC75/Nixie4IN14(a library)That's my first electronic project.Could you please check that everything is done right, and there's no serious mistakes?It seems to work fine, but I'm not sure if it's safe to recommend others to build this clock.Thanks
Yet another Jim Williams Pulse Generator - Page 1
Forum section: electronics / projects

author: dc101
author_rank: Regular Contributor
timestamp: March 27, 2014, 03:46:58 am
content: I've been wanting to build one of these Jim Williams pulse generators for a while. I'm pretty excited I finally had a chance to build it tonight. I've had the parts for almost a week. Usually my ADHD gets the best of me and I have to fix about 4 or 5 mistakes, but I must have been on my game tonight, I only had one mistake! At any rate, here's the results of my build. JPEG attached, ~520ps rise time... not too bad I guess considering the build.

author: Vgkid
author_rank: Super Contributor
timestamp: March 27, 2014, 05:25:28 am
content: Is that a Lego wheel I see?

author: dc101
author_rank: Regular Contributor
timestamp: March 28, 2014, 01:07:53 am
content: Quote from: Vgkid on March 27, 2014, 05:25:28 amAhhhh why yes, yes it is. Kidsgotta love 'em. I have a rather large UHF satcom filter that is considered by the small people to be the "crystal of power" so I often find Lego people, Barbie dolls and other random pieces of toys shoved in various drawers and compartments of my "lab."

author: Vgkid
author_rank: Super Contributor
timestamp: March 28, 2014, 02:50:45 am
content: I still have a rather functional bunker that i made out of Legos, and about a thousand single Legos.What is your scope?

author: marshallh
author_rank: Unknown
timestamp: March 28, 2014, 04:49:20 am
content: Nice R&S
Yet another Nixie Clock - Page 1
Forum section: electronics / projects

author: profdc9
author_rank: Frequent Contributor
timestamp: March 02, 2020, 03:23:35 am
content: I designed a Nixie Clock using IN-14 tubes and all through-hole components to make an easy kit. Check out a video of it hereYou can find the schematics, PCBs, code for it here:http://www.github.com/profdc9/NixieClockIt shows time, date, temperature, and humidity.Enjoy!

author: awallin
author_rank: Frequent Contributor
timestamp: March 02, 2020, 06:14:52 am
content: does it sync to NTP over wifi or wired ethernet? (and how does temp/RH get into the device)what is the lifetime of nixie-tubes - years I would hopeupgrading the schematics from kicad 4 to latest kicad 5 might help others work with your design..

author: profdc9
author_rank: Frequent Contributor
timestamp: March 02, 2020, 04:44:24 pm
content: It doesn't sync to NTP, but I have a connector on it for a GPS module to get the time. I haven't implemented it yet though. It uses the DHT22 module for temperature and humidity and a DS3231 for a RTC.I use the Nixie tubes at a fairly conservative current, but since I haven't run it for a long time I'm not sure how long it will last, but it should be yearsI need to update the projects from v4 to v5, just haven't done it yet, because v4 works well for my purposes. The only change needed should just be to swap some library symbols and footprints to newer versions in the v5 library.Dan

author: Wimberleytech
author_rank: Super Contributor
timestamp: March 02, 2020, 06:26:00 pm
content: Nice work.I am nostalgic about these. When I started electronics, much of the test equipment was nixie based.I keep telling myself to get a nixie clock but I don't know if I want to build it or buy it. There are arguments for each option.

author: schmitt trigger
author_rank: Super Contributor
timestamp: March 02, 2020, 06:39:06 pm
content: I love Nixies and all of the vintage glow displays, Dekatrons, neon lamps, bargraphs...Have you implemented a routine to prevent the cathode poisoning?

author: profdc9
author_rank: Frequent Contributor
timestamp: March 03, 2020, 12:41:29 am
content: I currently have a button if you press and hold for 2 seconds turns on each element for 1 minute to prevent cathode poisoning. Not sure what else I should do besides that. I suppose I could do 10 minutes or something like that to be sure.

author: xavier60
author_rank: Super Contributor
timestamp: March 03, 2020, 12:54:28 am
content: With my clock, I didn't worry about poisoning of unused digits because they will never be seen, unless the tubes are swapped some day.
Yet another PCB business card (with touchpad and LED matrix) - Page 1
Forum section: electronics / projects

author: allanw
author_rank: Frequent Contributor
timestamp: August 16, 2011, 02:42:21 am
content: Hey guys, I just started my next project,a PCB business card with capacitive inputs, inspired by Dave's uCalc form factor. I already posted it on Reddit earlier today and had a few comments, so I might as well just link to the comments:http://www.reddit.com/r/electronics/comments/jjodf/yet_another_pcb_business_card_with_touchpad_and/Here's the top board, with the touchpad. The bottom board will consist mainly of an LED matrix and some shift registers.Looking for general comments/suggestions. Also ideas about what to do about PWMing the 7x9 LED matrix. I'm leaning towards using a second microcontroller, probably a tinyAVR, to handle it, since this 4 MIPS PIC is really too slow for 8+ bits.I'm probably moving it to a two CR1620 design side-by-side, to be able to use blue and green LED's and keep it within 3.6mm thickness.

author: mobbarley
author_rank: Regular Contributor
timestamp: January 15, 2012, 08:54:39 am
content: Did you ever get this crazy idea going??

author: allanw
author_rank: Frequent Contributor
timestamp: January 15, 2012, 08:59:32 am
content: Got the boards back a while ago, the LED's shine OK through the thin white PCB. However the copper sections are not transparent at all, unfortunatelyNot sure how to continue the project.I'll have some pretty neat projects coming up soon that I'll actually have motivation to finish though

author: mobbarley
author_rank: Regular Contributor
timestamp: January 15, 2012, 12:03:02 pm
content: Could it be solved by making each touch pad hollow with a circle cut out of its centre?I made a pcb business card last year that is a little different to most - I'll have to write it up soon.

author: allanw
author_rank: Frequent Contributor
timestamp: January 15, 2012, 05:53:57 pm
content: Ah, that's a great idea.The best capacitance detection method uses mutual capacitance between plates so it only matters if there's some perimeter. I'll have to give that a try.

author: mobbarley
author_rank: Regular Contributor
timestamp: January 15, 2012, 11:46:39 pm
content: Once you have a working prototype and want a batch built it could be improved a bit further by using the right pcb service - some can make 2 layer boards down to 0.4mm (16 mil) half that of iTead. In addition if you are careful with traces around your battery holder you could order solder mask on the outside only and leave the inside uncoated, one less layer for the light to penetrate.
Yet Another Simple Dummy Load Circuit (with problems) - Page 1
Forum section: electronics / projects

author: brainpowered
author_rank: Newbie
timestamp: December 26, 2020, 08:13:50 am
content: Backgroundi've been wanting to build my own very simple dummy load for a few yeas now. And now i've finally put some parts on a breadboard. At first (or third) try, it all seemed to work. However occasianlly, something wierd goes on and then the circuit kinda behaves funny.(see third attachment)So,1. a Potentiometer sets the Current (1V/V basis)2. first opamp 'follows' set current voltage and drives the mosfet3. a 0.1Ohm sense resistor provides feedback to the 'feedback opamp' with a gain of 10xIn theory the circuit should work as a simple voltage follower, right....?(see first attachment)Well, sometimes... So it managed to work on a breadboard, somehow, at some point, i thought it worked, but now that i decided to build a Protoboard version, it really didn't work at all!The Current floiwing thought the Mosfet it either waaay too high, or other times it's waaay too low, it seems to behave differently each time i built a new version of it on a breaboard, the exact same circuit....! Gremlins? Or just a misunderstanding in Opamp theory.... whats wrong here guys, .... i'm at my wits end.I thought my circuit theory was on my side, but alas, here I am, asking for help.What do you guy think? (ignore the 'Fan Controller' block for now, it actually works great!)My schematic may be slightly oversimplified, but EasyEDA seems to lack standard symbols, or i'm just completely amateur.I've also included a Fritzing diagram for how i plan on wiring it a breadboard.(see second attachment)

author: opampsmoker
author_rank: Regular Contributor
timestamp: December 26, 2020, 01:13:12 pm
content: You need to set the error amplifier (opamp) up as an integrator.Attached is the kind of thing..its in the free download LTspice

author: ledtester
author_rank: Super Contributor
timestamp: December 26, 2020, 02:11:38 pm
content: Here's a recent forum thread on designing an electronic load that you may find helpful:https://www.eevblog.com/forum/projects/constant-current-dummy-load-ran-a-gutter/

author: magic
author_rank: Super Contributor
timestamp: December 26, 2020, 02:19:40 pm
content: That's not unity gain, its 0.1x gain. The output moves 100mV for 1V change in input voltage.Furthermore, the transistor adds some phase delay which may destabilize a unity gain stable opamp even at unity gain (without the 10x feedback amplifier).The regulation amplifier (call it A1) likely oscillates in this configuration and goes nuts.Common solution: resistor between A1 input and A2 output and a small capacitor from A1 output straight to A1 input.There was a dozen threads about it, which may give you some starting points for experimentation.BTW, A2 can be dropped altogether and input voltage to A1 divided 10x instead. Barely any difference in accuracy, possibly more bandwidth achievable that way(?)
Yet Another SMD Reflow Hotplate - Page 1
Forum section: electronics / projects

author: fourfathom
author_rank: Super Contributor
timestamp: August 20, 2021, 04:28:59 pm
content: Here's one I just discovered, using an electric iron (as used to hand-iron clothes). Pretty clever! As the builder mentions, the cool-down is going to be a bit slow. Really nice project documentation.https://makermoekoe.com/2020/04/28/maker-moekoes-kind-of-soldering-iron/https://github.com/makermoekoe/Hotplate-Soldering-Iron

author: fourfathom
author_rank: Super Contributor
timestamp: August 20, 2021, 04:50:38 pm
content: I guess this "makermoekoe" guy is pretty prolific. Here's one of his Youtube videos showing laser-cutting a solder-paste stencil and using that iron-reflow jig. Those SMD components look pretty big, I don't think he's going to be making stencils for 0402 parts...He has another video where he solders a larger board on that iron-reflow, and he apparently the board is warped (or warping) enough that he is pressing down the corners during the process. I think I get more uniform heat with my toaster-oven reflow.
Yet another Spot Welder - or is it not. Max Weld - Page 1
Forum section: electronics / projects

author: anishkgt
author_rank: Frequent Contributor
timestamp: February 15, 2018, 07:51:34 pm
content: Hi All,Just finished with a long time project i had been working on. All doing after my day work during the weekends.I did not have this project in mind till had those cheap Chinese ones failing several times. So figured why not make a replacement PCB and have the enclosure but out of frustration i dumped the enclosure and sold the parts at the local market. The Sunkko often failed due to the cheap TRIACs that came with them most of them being salvaged from old boards or cheap ones with no brand names manufactured in china.I took it a step further and designed a dual SCR that can handle 16A each. Making them more robust. Always switches at the peak of the Sine wave so as to reduce inrush current and turned off at the reverse polarity. A standard practice seen in inductive loads such as motors.

author: anishkgt
author_rank: Frequent Contributor
timestamp: February 24, 2018, 04:12:49 am
content: The schematic if anybody wants it.
Yet Another TruePosition GPSDO - Page 1
Forum section: electronics / projects

author: LazyJack
author_rank: Frequent Contributor
timestamp: February 22, 2021, 11:53:02 am
content: As the subject says. I've come up with Yet Another TruePosition GPSDO and I'm sharing the design files and software for it.It's a TruePosition board, controlled by an STM32 BluePill and sporting a 128x64 LCD display.I've put the details on my blog:https://diysquared.blogspot.com/2021/02/yatg-yet-another-trueposition-gpsdo.htmlAny feedback is welcome.

author: ZigmundRat
author_rank: Regular Contributor
timestamp: February 22, 2021, 03:01:14 pm
content: Thanks for sharing. I have a couple of these as well, and this gives me a few ideas for packaging, etc. Like you, I’ve had these kicking around for a while. They should really be put together in a completed project. You did a nice job with yours.

author: bingo600
author_rank: Super Contributor
timestamp: February 23, 2021, 02:30:03 pm
content: Nice buildupI also have a few of these GPS boards.What happens if power is lost , are you saving the position and reissuing coordinates ?Or do you perform a new survey ?/Bingo

author: LazyJack
author_rank: Frequent Contributor
timestamp: February 23, 2021, 03:49:23 pm
content: That is a good question. I actually put the function into the firmware to be able to save and restore the current position, but to me it looks like that if you do a survey, then the TruePosition saves the coordinates itself and will reload it after poweron without any additional effort.Otherwise it will acquire a fix anyway, even if you do not issue a survey mode. It will eventually lock. Besides, anytime I can issue a new survey.Still needs to be verified if and how much this affects accuracy.The firmware keeps track of uptime and last lock time, so in case of power outage this can be detected.However, you just gave me an idea to show on the status whether a survey was performed since the last poweron, as that would definiteley indicate if we are using the most accurate location.
YM2151 board with integrated Arduino and C64 expansion port connector - Page 1
Forum section: electronics / projects

author: FrankBuss
author_rank: Unknown
timestamp: November 14, 2019, 04:12:32 am
content: Just a quick hobby project I'm doing at the moment, for using an old YM2151 FM synthesizer chip. It is all open source hardware, circuit diagram:https://github.com/FrankBuss/ym2151/blob/master/KiCAD/YM2151.pdfUsing with the Arduino IDE:Using with the C64:

author: ebclr
author_rank: Super Contributor
timestamp: November 14, 2019, 09:03:26 am
content: NiceSimilar oneshttps://www.aidanlawrence.com/ym2151-arcade-classic-adlib-mini/
YOUHFU 16X Stereo Encoder Project – Unknown Varicap Diode? - Page 1
Forum section: electronics / projects

author: Chris56000
author_rank: Frequent Contributor
timestamp: September 20, 2023, 06:01:24 pm
content: Hi!Does anyone know what Varicap Diode can be substituted for this "MV115" quoted in this 16X Stereo Encoder please?It looks like the author filched the circuit of the Elenos ELC40 Stereo Encoder PCB EL09 circuit design, and made himself a Sprint Layout PCB from it!I'm happy to experiment with this and have a go building it (Boards on order!) but I can't identify the "MV115" varicap diode used on it, or find a data–sheet for it!nybody any suggestions?Chris Williams

author: DimitriP
author_rank: Super Contributor
timestamp: September 20, 2023, 06:37:55 pm
content: here is the whole enchilada in all its gloryhttps://www.qsl.net/yo4hfu/Files/STEREO_16X/ELC40%2040W%20EXCITER%20-%20ELC40UK_0.pdfThe MV115 is D1 in sheet 1/2 of the EL09 schematic on page 37 of the pdf.The higher MV numbers were usually "higher" C varicaps in to 100-300pf range.Since it looks like a manual adjustment, you could replace it with a variable cap.

author: Chris56000
author_rank: Frequent Contributor
timestamp: September 20, 2023, 06:52:38 pm
content: There are plenty of high–capacitance varicap diodes available, but I really need to know the maximum and minimum capacitance of the one Elenos uses, whether to use a fixed capacitor or not!Is there a typo in the part number quoted?Chris Williams
Your favourite buck converter [SOLVED] - Page 1
Forum section: electronics / projects

author: Unixon
author_rank: Frequent Contributor
timestamp: March 30, 2024, 07:03:30 pm
content: Hi!I'm looking for a buck converter that is capable of delivering 12V at 3-5A from Vin in range 30-40V.Something similar to TI's TPS565208 / TPS54302 but with higher Vin.What would be your part of choice for these parameters?

author: Unixon
author_rank: Frequent Contributor
timestamp: April 02, 2024, 04:28:12 pm
content: I completely forgot of another very nice TI's converter TPS54340 (TPS54540) which is exactly what I need.Looks like it's not the first time I had to find it...

author: mariush
author_rank: Super Contributor
timestamp: April 02, 2024, 04:56:41 pm
content: Don't have favorites for your scenario but looking at digikey i would suggest theseMP4316/MPQ4316 or MPQ4436 - 45V, 6A, Low IQ, Synchronous Step-Down Converteror MPQ4317 - same but 7A max currentmp4316https://www.digikey.com/en/products/detail/monolithic-power-systems-inc/MP4316GRE-Z/16499338ormpq4316https://www.digikey.com/en/products/detail/monolithic-power-systems-inc/MPQ4316GRE-5-AEC1-Z/15928484mpq4317https://www.digikey.com/en/products/detail/monolithic-power-systems-inc/MPQ4317GRE-5-AEC1-Z/16265436mpq4436https://www.digikey.com/en/products/detail/monolithic-power-systems-inc/MP4436AGR-Z/13982881orhttps://www.digikey.com/en/products/detail/monolithic-power-systems-inc/MPQ4436GRE-AEC1-Z/13180810also may want to look at dc-dc controllers so that you could have separate mosfets and maybe have 2 or more phasesexample Renesas ISL81601 (60v buck-boost 2 phase controller) :https://www.digikey.com/en/products/detail/renesas-electronics-corporation/ISL81601FRZ/9385329See page 5 in schematic, has the complete development board schematic for up to 60v in, 12v out at up to 10AShame it's a bit expensive

author: tooki
author_rank: Super Contributor
timestamp: April 02, 2024, 07:30:51 pm
content: Just as general info: TI’s Power Designer is, as far as I have found, unparalleled. I’ve designed multiple PSUs with its help.On the other hand, if you want to try out actual hardware, MPS’s evaluation boards and USB-i2C interface are far, far cheaper than TI’s. I’ve been meaning to get some to play around with.
your repair lifetime of switching power supplies? - Page 1
Forum section: electronics / projects

author: coppercone2
author_rank: Super Contributor
timestamp: November 24, 2018, 03:20:03 pm
content: I tried to fix a supply but I noticed the transformer was cracked, a fuse was blown and I got too lazy to fix the rest of it, so I just got some small ferrite beads and a to-220 condom from it.I figured dealing with all the MOV, capacitors, burned PCB, burned insulation, old fan and something that was shorting it out was not worth it.Do you trust SMPSU repairs? (this was a low end meanwell).How long do they usually last you? Assuming its not in something really expensive, how much damage do you tolerate before you decide not to do a repair?

author: coppercone2
author_rank: Super Contributor
timestamp: November 24, 2018, 03:23:15 pm
content: Quote from: blueskull on November 24, 2018, 03:22:35 pmmay be mechanical from throwing out

author: coppercone2
author_rank: Super Contributor
timestamp: November 24, 2018, 03:28:17 pm
content: maybe I had two identical ones? It's not like it was powered up after being thrown into a deep dumpster.

author: Ian.M
author_rank: Super Contributor
timestamp: November 24, 2018, 03:32:02 pm
content: If its not the MOVs, startup resistor, bad caps, cooked secondary side rectifiers or an obvious dry joint or lifted pad etc. its probably not worth fixing . . . .After replacing a failed startup resistor or bad caps, its often more reliable than original if you've used better quality components.

author: coppercone2
author_rank: Super Contributor
timestamp: November 24, 2018, 03:45:49 pm
content: interesting thing is they had ferrite beads on the mov legs. I never saw that before.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: November 24, 2018, 09:23:45 pm
content: Those weren't MOVs, those were Y-rated (line to ground) capacitors.Tim

author: coppercone2
author_rank: Super Contributor
timestamp: November 24, 2018, 10:27:15 pm
content: you are right
YouTube upload page never loads  *SOLVED* - Page 1
Forum section: electronics / projects

author: robrenz
author_rank: Super Contributor
timestamp: January 06, 2015, 02:19:04 pm
content: I am continuously getting a YT upload page that says loading but never does. If I go to the basic upload link it will take the information but it also just sits with no progress.I did find that others had the same problem and were firewall related but I never had any problems before with the same Trend micro virus software. I also added the upload url as a safe site and lowered the security level to the lowest and still no joy.Any ideas?screen stays here permanentlyEdit: working in a in private window solved the problem

author: David_AVD
author_rank: Super Contributor
timestamp: January 06, 2015, 08:56:05 pm
content: I've had youtube not want to play any video ("an error occurred") on different PCs using Firefox in the past few months. The solution was to delete all youtube cookies.

author: rdl
author_rank: Super Contributor
timestamp: January 07, 2015, 12:00:39 am
content: YouTube has been performing poorly for months. I get that "an error occurred" problem occasionally, but the problem I get most frequently is the video freezing when it auto-switches from low to higher resolution. They make useless changes way too often and don't test things worth a damn.

author: Cyberdragon
author_rank: Super Contributor
timestamp: January 07, 2015, 03:42:14 am
content: If you click the gear on the bottom bar you can lock the resolution."Trend micro virus software"

author: rdl
author_rank: Super Contributor
timestamp: January 07, 2015, 01:36:34 pm
content: I can only change and lock the resolution after the video starts, and they always start at either 360 or 480. Even after one is playing and set to 720 with the gear icon, new videos often still start at the lower resolution. Maybe it's because I don't save cookies between sessions (though they are allowed while connected), or possibly it's some JavaScript that's getting blocked. My whitelist is pretty short.
yujileds AP - Page 1
Forum section: electronics / projects

author: rounin
author_rank: Regular Contributor
timestamp: February 17, 2021, 08:00:19 am
content: Anyone use the yujiled AP series?https://store.yujiintl.com/collections/full-spectrum-ap-series-cri-98.Making some task&photo lighting using yujiled VTC flex pcbs but the AP series seem quite nice. I might get a few once the 5600k are back in stock.AP is bare LED only though, anyone know a place to get unpopulated flex PCB with lands for 3030 leds? Some quick searches don't really show what I want, mostly single 3030s or ribbons for 2835s.These guys have an al core board, but a 10mm flex would be better:https://www.cutter.com.au/product/mcpcb-3030560-lin/

author: rounin
author_rank: Regular Contributor
timestamp: February 18, 2021, 05:40:33 am
content: Got a few AP 5000k samples coming. Any major difference between the MEANWELL PWM-40-12 and NPF-40D-12? Is one PWM type dimming and the other current reduction dimming?https://yujileds.com/wp-content/uploads/2021/01/P3200007.00-2.0-YJ-AP-3030-G02.pdfhas a current vs chromaticity shift graphI can't really tell how big a deal it is, it shows like a +/-0.001 CIE1931 shift with current and like a 0.005 CIE 1931 shift with temperature. Think non-pwm current dimming is fine then wrt color shift?

author: knotlogic
author_rank: Regular Contributor
timestamp: February 18, 2021, 05:51:00 am
content: That's interesting, haven't seen those before.How do they compare to the their VTC series? Flipping between the product pages it looks like the AP is a bit higher in the orange and red regions and they filled in the drop between 400 nm and blue?

author: rounin
author_rank: Regular Contributor
timestamp: February 18, 2021, 06:23:15 am
content: I'll test them head-to-head when they get here. Yeah I think the main difference is in the both blue and red falling off more gradually and less blue spike / peak.

author: Zero999
author_rank: Super Contributor
timestamp: February 18, 2021, 11:00:39 am
content: I wonder how they work?The peak in the 420nm, implies they use violet, rather than the usual blue LED to excite the phosphors. There are other peaks in the blue, green and red regions, which is indicative of a triphosphor mix.
YX8019 Component - Page 1
Forum section: electronics / projects

author: bostonman
author_rank: Super Contributor
timestamp: April 09, 2021, 02:17:46 am
content: I have some LED solar lights that are having issues. Long story short, I was interested in seeing the circuitry and discovered they have a YX8019.Looking online, datasheets are in Chineese, but an old EEVblog message has a YX8018 translated that I believe is nearly identical.https://drive.google.com/file/d/0BwZTKiltzKYzTDJQYjdQMzhNVEU/viewAnyway, looking at figure 1-2 which seems to match the circuit I traced, I'm baffled by how the LED turns off when sunlight hits the panel. If pin 1 pulls the line to ground, that would turn off the LED, but draw excess current from the solar panel and not charge the battery. If the solar panel voltage is higher than 1.2v, which would turn off the flow of current from the battery, the LED would still turn on.

author: bostonman
author_rank: Super Contributor
timestamp: April 10, 2021, 01:36:00 pm
content: I disassembled another type and discovered this one has a black dot (epoxy?) on the board. I'm assuming a different component is used and epoxy is placed over for protecting against water/humidity.
Z80 video board - Page 1
Forum section: electronics / projects

author: minibutmany
author_rank: Regular Contributor
timestamp: January 23, 2013, 03:58:29 pm
content: HiI have been working on a small CP/M Z80 microcomputer and everything is going pretty good except for the output. I have very little idea of where to start in terms of making a video board. I would like it give at least some black and white text and use RCA or some other standard way of connecting to a TV. The idea with this project was to use only ICs that were available in the 80s and early 90s, but all the designs I have found use some super fancy microcontroller more powerful than the Z80 itself. What are some simple circuit solutions to video output that are compatible with an 8-bit CPU?

author: Skimask
author_rank: Super Contributor
timestamp: January 23, 2013, 04:16:35 pm
content: MAX7456..easy...simple...not really cheap.

author: SeanB
author_rank: Super Contributor
timestamp: January 23, 2013, 04:20:23 pm
content: Look at the schematic that Woz made for the 6502, it uses almost nothing and doubles as ram refresh as well.There were a few S100 bus video outputs that used an integrated controller, but I am not sure it is made any more so you will either be using old stock or pulls.I think a 6845 works, and there is info athttp://interbutt.com/mess/super80/for the standard TTL version.

author: grumpydoc
author_rank: Super Contributor
timestamp: January 23, 2013, 05:56:01 pm
content: 6845 was very common as a timing generator back then so it would be entirely appropriate if you wish to stick with contemporaneous chips.There are also the TMS9918 and Yamaha 9938 & 9958.

author: free_electron
author_rank: Super Contributor
timestamp: January 23, 2013, 06:55:59 pm
content: just hook it up to an LCD panel. There are graphics panels with COG that can do 80 characters or more by 8 lines.

author: nctnico
author_rank: Super Contributor
timestamp: January 23, 2013, 09:26:52 pm
content: Quote from: grumpydoc on January 23, 2013, 05:56:01 pmI vote for the Yamaha V9938 and V9959. Like the Z80 they where used in MSX2 MSX2+ computers and are actually quite powerfull (hardware line drawing, copy with mask, sprites, etc).http://en.wikipedia.org/wiki/Yamaha_V9938http://www.ebay.com/itm/609938-YAMAHA-V9938-VDP-IC-MSX-/400113102788

author: andersm
author_rank: Super Contributor
timestamp: January 23, 2013, 11:24:06 pm
content: The bookThe ZX Spectrum ULA: How to Design a Microcomputercontains a full description of the video circuitry of the ZX Spectrum, and it has beenrecreated in programmable logic.

author: svofski
author_rank: Regular Contributor
timestamp: January 26, 2013, 02:22:33 am
content: Usually old computers would share the video memory with CPU. Some had transparent scan (as in accessing video memory while the CPU is waiting), some had more complex bus arbitration (= hard to predict execution times), some had nothing (= snow effect).Have you considered going retro all the way and using Intel 8275 CRTC together with Intel 8257 DMA controller? That would be text-only though. I'm not sure how easy they are to find these days.
zebra strip contacts for LCD - Page 1
Forum section: electronics / projects

author: red_mamba
author_rank: Contributor
timestamp: February 28, 2011, 12:11:00 pm
content: Any one knows where to get this?

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: February 28, 2011, 04:59:17 pm
content: The classic answer would be try ebay ...Even so, the zebra strip contacts , its one product not so widely available.The quality of it , it is very important in long term.And the even more worst fact are, that on ebay many people are trying to rip you off.About the fact , if it worth it , to search for zebra strip contacts ..Its all about the cost of the device that you own.Anything cheapy as device, it does not worth repairing it.And my general advice are , do not mess-up with your LCD display or zebra strip contacts , if both of them works as it should.

author: red_mamba
author_rank: Contributor
timestamp: February 28, 2011, 05:45:24 pm
content: Am not repairing anythingI got tiny LCD's for my customer and I need zebra strips to connect them to my PCB

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: March 01, 2011, 02:57:30 am
content: In this case you have a big problem.You should order the specific (in specs) zebra strip, that works with the LCD that you got.And to build the PCB accordingly.

author: neoone
author_rank: Regular Contributor
timestamp: March 01, 2011, 10:40:48 am
content: I know one store that has thosehttp://www.elektroniksc.com.pl/?sGrupa=PODZESPO%A3Y&p=main&str=2(items 0088, 0076, 0074, 0064) but I don't suppose that you know polish languagePrices are in PLN, it's a rather small site so probably they don't sell abroad very often.

author: red_mamba
author_rank: Contributor
timestamp: March 01, 2011, 12:00:32 pm
content: they have what I needhave send them an email, will see

author: red_mamba
author_rank: Contributor
timestamp: March 07, 2011, 10:43:04 pm
content: There site is down and my initial email contact is not respondingAny other source?
ZEEWEII DSO2512G  DC 5V RIPPLE MEASUREMEMENT - Page 1
Forum section: electronics / projects

author: Gebrey
author_rank: Newbie
timestamp: April 01, 2025, 03:25:42 pm
content: Hallo everyone,I hope to be in the right forum section.I bought DSO2512G as suggested from forum members.Now, Im making some easy test to become confident with it.Ive got an arduino DHT22 X8 sensors that works ONLY with a specific 5V source. The APPLE OLD USB 5V PSU (the quartz shaped one. 5V 1A USB-A).I want to investigate about.Tested sources:- Apple 5V1A old USB A psu (fail just one sensor 10% of time probably due to the lenght and the connection of that sensor)- DCDC 13V LIFEPO4 battery to 5V output (fail reading 90% of signals)- 5V USB C from a TUYA 12V 10x relays board (failing similar)- handmade L7805 voltage regulator with adeguate filter caps (failing similar)Now this thing is very odd. So since the supplied current is over 1A in all situation, the only other parameter is the ripple that could interferes with data signals timing of sensor with arduino NANO.I tought to enter in OFFSET mode and subtract 5V to see only the ripple. But unfortunatly I can only get to OFFSET MENU without any possibility to work with (MENU > Meas > CH1CH2 button > V button long press ).Can you help me? Im a really newbie to DSO and this model of DSO.THANKS

author: tunk
author_rank: Super Contributor
timestamp: April 01, 2025, 05:16:29 pm
content: Try to set it to AC coupling (not DC).

author: osmax_br
author_rank: Regular Contributor
timestamp: April 01, 2025, 05:23:01 pm
content: there is the decoupling modeDCAC : removes the dc part from the signal , you can view the ripple without dealing with the 5vI suggest watch w2eau videos on this matter

author: Gebrey
author_rank: Newbie
timestamp: April 01, 2025, 09:01:53 pm
content: Thank you bothThis is the situation. How is possible that GREEN (Apple 5V1A) has more ripple than YELLOW (DcDc 12V to 5V) BUT the Apple works and the other not?

author: Gebrey
author_rank: Newbie
timestamp: April 01, 2025, 09:42:38 pm
content: I thought that these 2 probes werent calibrated...These measures are made with the same probe.
Zelda BOTW's Cartridge Teardown - Page 1
Forum section: electronics / projects

author: Julien_Texplained
author_rank: Newbie
timestamp: May 30, 2017, 09:30:14 am
content: Hi everyone,Maybe some of you might be curious about what's inside a Nintendo Switch's cartridge.We just releasedthis articlewhere we proceeded to teardown the Zelda cartridge and analyze the Nintendo Switch cartridges’ security in general.I hope you will enjoy it and feel free to give us your feedbacks.We will keep posting new pictures of this cartridge and other devices on our Twitter (@Texplained_RE) so stay tuned!Have a good dayJulien

author: JPortici
author_rank: Super Contributor
timestamp: May 30, 2017, 09:55:20 am
content: edit the post, link is broken

author: wraper
author_rank: Unknown
timestamp: May 30, 2017, 10:23:22 am
content: It's certainly not ROM based (if mask ROM was meant by that), one would be insane to do this nowadays. Just a NAND flash IC with some flash memory controller in one package made by Macronix. What is that memory controller and it's security features is another question.

author: Zbig
author_rank: Frequent Contributor
timestamp: May 30, 2017, 10:38:13 am
content: Julien_Texplained, I personally don't like the way you make some far-fetched assumptions and make it sound like you know things you actually don't - you're just guessing.

author: wraper
author_rank: Unknown
timestamp: May 30, 2017, 11:18:41 am
content: Quote from: Zbig on May 30, 2017, 10:38:13 amThe largest mask ROM offered by macronix in their MX23L series is apparently 128M bit (16 megabytes). They also have "XtraROM®" MX23J with up to 1G bit (128 megabytes). They don't explicitly say what it is inside but certainly not mask rom as is programmed at factory. Still too small for modern games. If you need the right size for modern games, you have no choice other than NAND.

author: Zbig
author_rank: Frequent Contributor
timestamp: May 30, 2017, 11:28:15 am
content: Wraper, my remark was directed to the original poster. Sorry for not making that clear.EDIT:For all we know, it could just be a modified SD card and, as you said, the smaller die could just be a flash controller. Also, flash would have most sense for a game storage in regards to updates and patches. That's why I don't like how OP jumps to calling it a "security chip" and speculating how it could be circumvented.

author: wraper
author_rank: Unknown
timestamp: May 30, 2017, 01:20:59 pm
content: Security most likely is there, no copy protection is a very rare exception not a norm these days. Macronix offers optional security in other 23 series ICs as well.

author: Julien_Texplained
author_rank: Newbie
timestamp: May 30, 2017, 01:43:10 pm
content: Quote from: Zbig on May 30, 2017, 10:38:13 amHi and thank you for your feedback.Even if I don't really understand the purpose of your comment.Yes we made some assumptions because we would like to know how it works, that's generally how studies workAt this stage of the study it was too early to affirm anything hence the guesses and the use of "could".Now that the Chip ID is almost finished we have more answers and we can confirm (or not) our assumptions.Regards
Zener clamping at microamp supply levels - Page 1
Forum section: electronics / projects

author: jmoschetti45
author_rank: Contributor
timestamp: September 19, 2019, 06:44:29 pm
content: Long story short, I have an input of 4-125VAC I need to measure with a comparator. Preliminary testing shows I'll need my threshold to be around 12V. The comparator portion is easy.My problem is the variable voltage, or I'd just use a cap dropper to drive the opto.My thoughts are a simple full bridge with a series resistor with a zener. To keep the dissipation down, I'd shoot for something like 220k or 330k. I don't remember the op amp's input current requirements off the top of my head (LM358 ....have a ton laying around).Usually, I'd just use a zener to limit the voltage, but will the 1mA or less cause issues with the zener?

author: jmoschetti45
author_rank: Contributor
timestamp: September 19, 2019, 07:05:55 pm
content: Quote from: blueskull on September 19, 2019, 06:51:33 pmI'm seeing a max of 7V in the datasheet?

author: magic
author_rank: Super Contributor
timestamp: September 19, 2019, 07:26:12 pm
content: There is a million xx431x parts differing in reference voltage (1.24/2.495/2.5), operating current range and abs maximum voltage.Quick parametric search brings: SC431, LMV431
Zener clipper cct (help request) - Page 1
Forum section: electronics / projects

author: Cliff Matthews
author_rank: Unknown
timestamp: April 19, 2018, 05:53:53 pm
content: Just a low budget project with most parts I've collected for a while. I'm wiring a flexible bank of transformers supplied with 2 types of variable mains regulation:1) transformer buck/boost 2) zener clipper using 4x 50watt studs each with 6amp rectifier (so zeners only work half cycles)Questions: Provided I have good heat sinking, is the clipper cct's fuse size correct? and can this cct be optimized?The caps everywhere I assume will smooth noise, will they make much difference?edit:Sorry, fuses, switches, diodes are missing in TINA (diodes are *6A08's, etc.. Go easy, this old guy is still learningand I've had those expensive NOS zeners for 20+ years and a bunch of .022uf 600v film caps just itching to get used..
Zener diode tester - Page 1
Forum section: electronics / projects

author: johnwa
author_rank: Frequent Contributor
timestamp: January 04, 2024, 03:41:21 am
content: Hi everyone, here is a little project I put together over the Xmas break - a handheld tester for determining the breakdown voltage of zener diodes. The circuit isn't anything special at all - just a boost converter and a panel meter module - but it is proving to be quite a handy little tester, well worth having in the lab.Further details, and a circuit, are over athttp://loopgain.net/zenertester/if you'd like to try building one.

author: enut11
author_rank: Super Contributor
timestamp: January 08, 2024, 06:57:17 am
content: Hi@johnwa. Nice little project. I am an incurable electronic gadget man but for zener testing I use my power supply set to a constant current of a few mA. Starting at zero I wind up the volts until CC sets in and reveals the zener voltage.enut11

author: johnwa
author_rank: Frequent Contributor
timestamp: January 15, 2024, 09:38:10 am
content: Thanks, enut11! If you only need to test zeners occasionally, using a power supply is not a bad way to test them.(For anyone else who wants to try this, make sure you follow enut11's advice exactly, and wind the voltage up slowly from zero - many power supplies have poor transient response and/or excessive output filter capacitance, which could otherwise result in damage to the DUT)

author: SeanB
author_rank: Super Contributor
timestamp: January 15, 2024, 12:28:30 pm
content: I made one years ago, using old small transformers I had. wired 2 back to back to give an isolated supply of around 100V, then made a simple constant current source of 10mA with it. 4 terminals, 2 for the DUT, and 2 for the meter probes, and it was done. Also came in handy testing small relays, and other things like charging up old capacitors, to see if they were leaky.

author: watchmaker
author_rank: Unknown
timestamp: January 31, 2024, 03:01:43 pm
content: Quote from: enut11 on January 08, 2024, 06:57:17 amTHANKS for this. I was wondering how to verify and select zeners. Quick and easy.

author: magic
author_rank: Super Contributor
timestamp: January 31, 2024, 04:35:02 pm
content: I would add a few kΩ resistor between the output capacitor and test terminals in order to limit surge current when the zener is connected. Or your fingers.Such thing could also be used to test low voltage transistors, but I found that my jellybeans like BC547 or 2N3904 tend to exceed 100V...

author: johnwa
author_rank: Frequent Contributor
timestamp: February 01, 2024, 11:21:15 am
content: Quote from: magic on January 31, 2024, 04:35:02 pmThat's not a bad idea, in fact C2 could probably just be connected to the other side of R2.Quote from: magic on January 31, 2024, 04:35:02 pmYes, there is sometimes a quite surprising difference between the rated value, and what they will withstand in practice. Of course, a diligent engineer will not rely on this, but it's great if you need a one-off for a repair or something.
Zener in rectifier - Page 1
Forum section: electronics / projects

author: Karatzinis
author_rank: Newbie
timestamp: April 11, 2019, 10:55:54 pm
content: HiCan I use a zener diode, e.g. Vz=43V, in a rectifier to suppress overvoltages while it is in blocking state (nominal blocking voltage is 30V). A diode of 40V sometimes is damaged from voltage spikes. Could a zener be a solution ? When using a zener it seems to supress the peak voltages but is there any danger for short circuit the output or break down ?Thanks in advance.

author: Hiemal
author_rank: Regular Contributor
timestamp: April 12, 2019, 12:43:49 am
content: I don't think you're using the zener correctly here.Is something more appropriate I think.

author: ArthurDent
author_rank: Super Contributor
timestamp: April 12, 2019, 12:44:37 am
content: Just use a higher rated rectifier diode in the 100 to 600 volt range. If the ringing you show in your drawing is from a switching mode power supply, make sure you use a fast diode.

author: David Hess
author_rank: Super Contributor
timestamp: April 12, 2019, 04:58:50 pm
content: If breakdown across the normal rectifier is damaging it, then using a zener may not help. Also, zener diodes are slow and not suited for switching power applications.An avalanche rated rectifier may be exactly what you need. Like TVSes but not zeners, they use special processing so that reverse breakdown takes place uniformly across the junction instead of allowing hot spots to form.

author: Karatzinis
author_rank: Newbie
timestamp: April 15, 2019, 05:52:57 pm
content: Thank for the responses, I think I will just go for a higher rated typical diode. More general, even using TVSs I wonder if it's good practice to have a component in a rectifier that can partly "open" to suppress any voltage spikes that could appear.