hybridfree/eevblog-posts huggingface dataset:
... - Page 1
Forum section: electronics / projects

author: cleaningOut
author_rank: Contributor
timestamp: April 17, 2015, 01:01:37 am
content: ...

author: Blasterbug
author_rank: Newbie
timestamp: April 21, 2015, 08:06:40 am
content: Hi there,How did you finally control the matrix shit ?

author: Blasterbug
author_rank: Newbie
timestamp: April 29, 2015, 12:51:13 pm
content: To me, it appears Arduino wire library doesn't support totally I2C protocol, I usehttp://dsscircuits.com/articles/arduino-i2c-master-libraryinstead. And I am now able to get data from Matrix controller.I create a GitHub repository to promote my library. Take look athttps://github.com/blasterbug/Matbotics

author: Blasterbug
author_rank: Newbie
timestamp: April 30, 2015, 08:48:50 am
content: Yes, I used Arduino Mega 2560. But I think the I2C library is design for all Arduino boards. I probably made a mistake thinking this way.I don't know much about the bitrate. But I know also signals are 5V, it's the I2C reference used by Arduino and the NXT, so the Matrix controller should work at the same voltage.My library is much about how to send I2C commands to the controller rather than which type of signals it uses.

author: Blasterbug
author_rank: Newbie
timestamp: June 10, 2015, 12:38:15 pm
content: I updated my library, It is now possible to read battery level and some more stuffs like controller status, etc.I made a good demo of the controller used by a Arduino board ...

author: Mechatrommer
author_rank: Super Contributor
timestamp: June 10, 2015, 01:30:49 pm
content: Quote from: cleaningOut on April 17, 2015, 01:01:37 amsoon you'll realize it is not the NXT or ROBOTC that is junk... fwiw NXT has 32bit 48MHz ARM and another 8bit coprocessor, if you cant get that right then

author: Blasterbug
author_rank: Newbie
timestamp: June 29, 2015, 08:59:19 am
content: Quote from: Mechatrommer on June 10, 2015, 01:30:49 pmHi Mechatrommer,True, I already know that. In deed, NXT has a processor and his other coprocessor is in fact another micro-controller used to deal with devices. And good to know, NXT doesn't have a ship to deal with I2C. The whole I2C protocol is managed only with software. And this is a big junk.But whatever, I do not use NXT.
Writing Some Calculators - Page 1
Forum section: electronics / projects

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 02, 2015, 08:00:22 pm
content: http://seventransistorlabs.com/Calc/ResDiv.htmlShould look okay, obviously you'll need JavaScript to use them. Haven't ran W3C-Validate on anything yet. Try it on different browsers and platforms, see if it's usable or not?I have a bunch more yet to do, I'll update when they're ready.Tim

author: Lightages
author_rank: Unknown
timestamp: June 02, 2015, 08:06:33 pm
content: Thanks for sharing!

author: German_EE
author_rank: Super Contributor
timestamp: June 02, 2015, 08:40:38 pm
content: Works fine on Firefox 38 and Linux Mint (and the site is damn useful)

author: c4757p
author_rank: Super Contributor
timestamp: June 02, 2015, 09:06:24 pm
content: Verynice to include the double-output and biased dividers.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 03, 2015, 08:59:21 am
content: More:http://seventransistorlabs.com/Calc/Tempco.htmlTim

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 06, 2015, 11:23:24 pm
content: This should be pretty useful:http://seventransistorlabs.com/Calc/RLC.htmlAlso, made some updates/corrections to the earlier ones (mostly in HTML code).Tim

author: Richard Crowley
author_rank: Super Contributor
timestamp: June 07, 2015, 12:04:11 am
content: Great! Remember to add your pages to the list...http://www.eevblog.com/wiki/index.php?title=Online_references,_utilities,_calculators_etc.
Writing to ST25TB512 NFC tag - Page 1
Forum section: electronics / projects

author: Rachie5272
author_rank: Regular Contributor
timestamp: June 19, 2025, 06:08:47 am
content: I'm trying to work with ST25TB512 NFC tags. I'm able to read them with a flipper zero, but so far I have not been able to find anything which will write to them. The datasheet is very unclear on what tools are needed. Can anyone help?
Wrong resistor SMD code - Page 1
Forum section: electronics / projects

author: fedimakni
author_rank: Regular Contributor
timestamp: July 29, 2021, 08:29:25 am
content: Hello,Today I encountered a weird problem. My design contain a 100K ohm SMD resistor 0603 with SMD code 104. I used a prototype service to assemble the pcb in china. When i received the PCBs i found some of them don't behave correctly, after investigation i found that the resistor value (in some PCB) was around 36M ohm (correct value 100K ohm) the problem that the SMD code is also 104.Note: Some PCB work normally and their resistor is 100K ohmCould the factory make mistake by using resistors from the grey market which have the same SMD code? What are the possible reasons of such problem?Thanks again for your support.

author: SeanB
author_rank: Super Contributor
timestamp: July 29, 2021, 11:12:14 am
content: Probably cracked resistors, or recycled ones that were simply put in a tape for sale after being recovered from ewaste.

author: teletypeguy
author_rank: Contributor
timestamp: July 29, 2021, 05:52:23 pm
content: Are you sure the marked code is 104? The 0603 package is sometimes marked like that for 5% values -- 1% values (the E96 series) usually have a 3-digit code (2 numbers and one letter) that needs a lookup table to read. You find that even the 5% (E24) values, if ordered as 1% will use the E96 markings. So if you order a 5% 100K it will be marked 104, but if you order a 1% 100K it will (usually) be marked 01D. However, it depends on the manufacturer -- I have reels of 100K 1% marked both ways, from different manufacturers.Scroll to table at bottom:https://learn.sparkfun.com/tutorials/resistors/decoding-resistor-markings

author: fedimakni
author_rank: Regular Contributor
timestamp: July 30, 2021, 05:43:34 am
content: Hello,Thanks for the reply,Yes I am sure they have 104 code on the top of them.

author: bson
author_rank: Unknown
timestamp: July 31, 2021, 05:57:32 pm
content: Probably cracked during reflow, cleaning, or in shipping.

author: Gyro
author_rank: Super Contributor
timestamp: July 31, 2021, 06:16:17 pm
content: The test is whether it unsolders in one piece or two.

author: gamalot
author_rank: Super Contributor
timestamp: July 31, 2021, 08:41:21 pm
content: Quote from: SeanB on July 29, 2021, 11:12:14 amNo one will recycle such cheap components. A whole wheel of 5,000pcs 0603 resistors is only worth about 2 US dollars in China.
Wrong wire insulation size  - Page 1
Forum section: electronics / projects

author: Sparks
author_rank: Contributor
timestamp: January 20, 2015, 10:57:50 pm
content: Just to put this out there, I bought a 1000' spool of 22g solid wire from jameco.com. When I went to use it there was something a little off. My automatic wire strippers have always worked perfect on my old spools of 22g, but this time the wire just slips right between the cutters. The wire itself is the proper size but the insulation is just really thin.Never encountered this one before, gotta slow down my work slightly and go back to the old adjustable strippers.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 21, 2015, 03:04:28 am
content: Is it that slippery hard stuff, too? Teflon or kynar or whatever?I always just get good old Alpha 3051...Tim

author: cosmicray
author_rank: Frequent Contributor
timestamp: January 21, 2015, 03:18:23 am
content: That sounds like Teflon insulation. If it is, beware of pulling it tight when turning sharp corners. Funny things may begin to happen several years down the road.

author: Sparks
author_rank: Contributor
timestamp: January 22, 2015, 07:45:34 pm
content: It's a PVC insulation,http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_36805_-1

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 22, 2015, 10:00:02 pm
content: 105C PVC, 10 thou jacket. Well, there you have it!Seems curious that it's 600V rated. I wouldn't suggest actually using it for that, certainly not around sharp chassis corners and edges and stuff...Tim

author: Sparks
author_rank: Contributor
timestamp: January 22, 2015, 11:03:02 pm
content: Didn't even notice that in the datasheet. Gonna need to review those a bit more carefully.
Wrote a tutorial on LtSPICE. Feedback welcome - Page 1
Forum section: electronics / projects

author: ghani256
author_rank: Contributor
timestamp: September 11, 2016, 02:24:52 pm
content: Hey guys. I recently wrote a primer on LtSPICE. You can see it on the link below.Your feedback and suggestions are highly welcome so that I may improve it. Thanks.http://techsology.net/2016/09/08/ltspice-tutorial/]http://techsology.net/2016/09/08/ltspice-tutorial/

author: alexanderbrevig
author_rank: Frequent Contributor
timestamp: September 11, 2016, 10:36:02 pm
content: Seems goodI would add shortkey descriptions as I found LtSPICE much more pleasant to work with after a few shortkeys is learned.BTW; You should fix the URL in your post.

author: StillTrying
author_rank: Super Contributor
timestamp: September 11, 2016, 11:32:55 pm
content: URLs in your post are broken, only had a quick look but your 4 tutorials are good for starters, and me!

author: ghani256
author_rank: Contributor
timestamp: September 12, 2016, 05:34:07 am
content: Quote from: StillTrying on September 11, 2016, 11:32:55 pmI will look into it and fix those. Thanks
WS-1 water sensor - Page 1
Forum section: electronics / projects

author: Ezink
author_rank: Newbie
timestamp: January 02, 2024, 06:54:07 pm
content: Hello everyone,I used to work quite actively with electronics design, so I even feel a sense of shame when asking, but I don't understand how the WS-1 water sensor works. It has two wires, red and black. I want to connect 10 sensors so that when one of them is triggered, the relay switches from NO to NC. I will design the further logic, but it is not clear to me how this sensor works and how to connect it. Maybe someone has experience with this WS-1 sensor and could you share a schematic of how to connect it?

author: ataradov
author_rank: Super Contributor
timestamp: January 02, 2024, 07:18:17 pm
content: The sensor seems to take +24 V power and has plain relay output with 3 contacts - Common, Normally Open (NO), and Normally Closed (NC). When there is no water detected, Common and NC are shorted. Once water is detected, Common and NO are shorted.If you want any of the 10 sensors to trigger the relay, then you can connect all commons and NO in parallel. If any of the sensors triggers, it will short the parallel connection. You can use that to power your secondary relay. Or just use the signal directly.

author: Ezink
author_rank: Newbie
timestamp: January 02, 2024, 07:29:54 pm
content: Thank you for replay, but incorect. As I mentioned, it have 2 wires, red and black, thats it. It looks like this:

author: pcprogrammer
author_rank: Super Contributor
timestamp: January 02, 2024, 07:31:45 pm
content: Hi Ezink, welcome to the forum.I found two versions of WS-1 on the net.TheAsurity® WS-1 Wet Switch® Flood Detector, which has a relay build into it and can be connected as ataradov wrote.And theTANE WS-1, which has only two wires, which you wrote. This one I suspect works with a difference in current. When no water is detected it draws only a small amount, and when it detects water it will draw a bit more. You can experiment with it when you have one. Take a 12V power supply and connect the sensor with a resistor in series. Lets say 1Kohm. Measure the voltage across the resistor when dry and when wet. You can then calculate the currents and design a circuit around it.If this is the case you can wire them in parallel. When one or more get wet the current will go up.Edit: @Ezink, I already wrote up my responseSo just focus on the Tane sensor.
WS2811 addressable LED driver unused pins - Page 1
Forum section: electronics / projects

author: danners430
author_rank: Regular Contributor
timestamp: January 29, 2019, 01:39:58 pm
content: Afternoon folks,I've got a project ongoing at the moment, involving umpteen tiles being installed in a control panel. These tiles are all different and mostly unique, but the various LED configurations can be generalised into 6 "master" designs, with only the necessary LEDs for the individual tile being added at installation. Saves me money on PCBsHowever, I've come across a minor problem - what do I do with unused pins on the driver chips, the WS2811? I'm guessing it won't do any harm leaving them NC, but would best practice be to tie them to ground, since the chip is open drain...?Any clarification would be much appreciated!!

author: Ian.M
author_rank: Super Contributor
timestamp: January 29, 2019, 02:05:08 pm
content: Where did you get the idea the WS2811 LED outputs are open drain? If one carefully reads itsdatasheet, it tells you that they are PWMed 18.5mA (typ.) current sinks, that drop 0.4V (presumably minimum). Why would you think grounding them would be desirable? Depending on how the current sinks are implemented, that could disrupt non-grounded outputs.

author: danners430
author_rank: Regular Contributor
timestamp: January 29, 2019, 02:25:07 pm
content: That was my assumption... hence my question - assumptions make fools!!I'm guessing then it would be more desirable to either leave them NC, or fit "dummy LEDs" in the form of resistors (3V @ 18.5mA ~ 160Ω)...?
WS2812 reflow soldering failure rate - Page 1
Forum section: electronics / projects

author: okaresz
author_rank: Newbie
timestamp: January 21, 2015, 03:24:17 pm
content: Good day,I have a board design with 12 WS2812 modules in a circle layout on the top (see attached picture, sorry for the poor quality, it's just for the layout). The first batch recently came back from the pick&place company, and when I started to test the boards, it turned out that on EVERY board, there are 2-3 LED modules are dead. I have however one board which I hand-soldered, no faulty LEDs there.Now I did my fair research on the WS2812 modules, and how reliable others found it. 1-3% failure rate can be said to be normal, during handling, mounting or during operation. Of course I too am dealing with IC-s ordered from china, so there is something to be said for a reliable source...But a consistent ~30% failure rate in a 50pcs board (600pcs LEDs) batch? Come on.. And since I haven't found a specific topic on the possible reflow failure of these LEDs, here is oneI'm using the older - 6pin - revision of WS2812, sometimes referred as "S" version. Additional to the standard docsheet, I found this soldering and reflow manual:http://www.insomnialighting.com/datasheets/WS2811RGB_WS2812_manual.pdf.I consulted with the P&P company, the peak of the reflow profile was to the specification (even below, ~ 220-230 celsius), for about 12s.There are LEDs which are completely blown, not even forwarding data, and there are a few in which just one of the colors is dead. I don't have a microscope or other inspection equipment, so I shot a few pictures with a macro lens:http://goo.gl/1I7zAIThe ones, marked with black corner are the faulty ones.That strange gooey stuff appearing to flow and crack beneath the top cover could be the silica gel, which the reflow manual mentions. The transparent top cover is completely undamaged, looks shiny and smooth, as it should, on every LED. I checked the soldering, it' totally fine.I hope some more experienced eyes can see more than mine.thanks,okaresz

author: langwadt
author_rank: Super Contributor
timestamp: January 21, 2015, 03:35:12 pm
content: Were they stored in a sealed bag and/or baked before soldering? If moisture gets inside they can crack from steam when soldering.That would also explain why hand-soldering works, because you are not heating the whole part just the pins

author: okaresz
author_rank: Newbie
timestamp: January 22, 2015, 11:24:43 am
content: Wow. That hit me in the head. I almost feel dumb, I guess I never really understood the importance of baking... till now.No, the chinese don't bother with moisture sealed bags, and I doubt the assembler baked the parts before reflow. So yepp, this can be a very possible reason, thanks!
WT2003H4 with decent sound quality? - Page 1
Forum section: electronics / projects

author: Paul.H
author_rank: Newbie
timestamp: July 19, 2025, 10:18:53 am
content: HelloI have a project where I'm using an ATtiny1614 to trigger a sound signal on the WT2003H4 chip. The sound is a simple bell tone stored as an MP3 file.I've tested various speakers, including 8Ω 0.5W, 8Ω 3W, and 4Ω 3W models. All speakers have a diameter of less than 36 mm, as this is the maximum size that fits inside the housing.At first, I used the PWM output and connected the speakers directly to the WT2003H4. The volume was acceptable, but the sound quality was poor—especially with low frequencies. There was a lot of crackling and distortion.I suspected that the internal amplifier of the WT2003H4 might not be powerful enough, so I switched to the DAC output and added an external amplifier. I tried several amplifier chips (NS4150B, PAM8302A, and LM4890). I connected them according to their respective datasheets and also configured the WT2003H4 for DAC output mode. However, the sound was extremely quiet—barely audible.Has anyone worked with the WT2003H4 and managed to achieve decent sound quality?
OK: Help making a C# project work (Thanks Rich) - Page 1
Forum section: electronics / projects

author: SL4P
author_rank: Super Contributor
timestamp: December 26, 2016, 09:37:58 pm
content: I'm a complete newbie with C# (a week), but have already attempted to put together my FIRST application that seems to work -exceptfor serial interfacing with asynchronous data bursts (up & down)from a custom embedded controller. (a config/setup utility)What i've done is in my opinion incredibly clunky (about 100 dynamically created controls on half a dozen tabbed pages).There are three functions on the connected device (which can be modified), does -1) download a map of memory addresses2) retrieve a block of data3) send a. lock of dataMy main current problem is synchronising the bursts of data coming and going - as somewhere i lose maybe 0.5% of my received data, or the 'receiver' tries to parse the same values more than once (?!)I haven't tried sending data back yet. The bi-di serial works, I think the issue is the threaded handling of the data to avoid race conditions.What i'm looking for is an experienced C# devnearbythat can work over my programming inadequacies, and (hopefully) close one eye to my C# learner status.I'm (literally) broke, (5 years) unemployed and that's unlikely to change in the near future (health), but I'm happy to figure a way to reward a contributor if a path can be found. The idea is this app will make my embedded project more saleable - and put some small bikkies in the bank. (I've sold around 25 of them already)The reason i need to find someone locally is the requirement to work directly with the host device, as well as opportunity to modify the host software interface if needed (ASCII serial @ 115200 bps).Drop a PMif you think you're bored enough to work for the least money man has ever seen.The effort could take as little as a single afternoon to a couple - depending on how good you are, and how much of my work you need/want to replace!Melbourne South-Eastern suburbs (~20 km from CBD)I can supply coffee trips, food court visits etc!

author: Julius
author_rank: Contributor
timestamp: December 28, 2016, 03:18:05 pm
content: Maybe you could try posting the relevant threaded excerpts of your code on the forum and get some feedback on that?

author: SL4P
author_rank: Super Contributor
timestamp: December 28, 2016, 09:53:12 pm
content: Thanks for the thought.i'll look at that, but the code is extremely interdependent (remember i said it was my first clunky attempt!)Hundreds of variables - effectively streamed.I know it's possible, just out if my current skill level!Will put it up if i don't find a saviour.Thx.

author: Tony_G
author_rank: Super Contributor
timestamp: December 29, 2016, 02:45:05 am
content: Create a GitHub repo for the code - Point people at it - Be prepared to take fixes being submitted.I know that might be a bit much for a new user but this will give you a solid base moving forward and let people contribute to your project.As long as your project builds and can "run" (doesn't need to have the HW to execute) then people can propose changes (I'd be happy to throw a few in).TonyG
WTF - can't reach Altium (10) Document Parameters...! - Page 1
Forum section: electronics / projects

author: SL4P
author_rank: Super Contributor
timestamp: February 21, 2016, 12:06:31 am
content: I've just started a new PCB project, and working in the schematic editor, I want to set the document parameters etc.I opened the Sheet-Options panel, but can only scroll within about 2/3 of th elist of variables... the bottom items (Title etc) are out of reach!Any thoughts ?

author: marshallh
author_rank: Unknown
timestamp: February 21, 2016, 12:13:01 am
content: Resize the main window? The listbox may be a fixed size and have been truncated by the dialog.Is your screen resolution set low?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 21, 2016, 03:41:37 am
content: Windows desktop setting: turn off 125% text size.Tim

author: marshallh
author_rank: Unknown
timestamp: February 21, 2016, 05:39:45 am
content: Ah right, the old DPI breakage that ensures basically nobody used it.I tested Altium 15 on Windows 10 and surprisingly all UI stuff sized correctly no matter the DPI! It only took 3 decades...

author: SL4P
author_rank: Super Contributor
timestamp: February 21, 2016, 01:31:13 pm
content: Thanks for the tips...Normally I see the problem pretty quickly, but in this case, all the windows are away from the edges, and the scroll works fine - just not to the bottom opf the list... !I'll get back into it tomorrow.Thanks again.

author: SL4P
author_rank: Super Contributor
timestamp: February 21, 2016, 10:05:28 pm
content: Thanks guys - I should have used my brain before engaging the keyboard...A pretty weak UI effort - considering the amount of work they put into the graphical elements!(CLOSED)
wtf is a "3/4-length" PCIe card ??  - Page 1
Forum section: electronics / projects

author: frogblender
author_rank: Regular Contributor
timestamp: April 09, 2021, 03:22:41 am
content: The boss told me today to design a"3/4-length"pcie card (for the latest skynet chip, but that's neither here nor there).But checking the PCIe card Electromechanical spec ver 2.0 (I think we are too cheap to spring for a pcisig membership, so we have the 2.0 spec), it makes no mention of "3/4", "three-quarter", nor any other such variation. Itdoesspeak of half length and full length thusly:half = 6.600" (167.65mm for the metric fanboys)full = 12.283" (312.00mm for mfb's)Anyone know what a 3/4-length pcie card is? Or perhaps you have the pcie "Card Electromechanical Spec" ("CEM") rev 4.0? (maybe the sly foxes slipped in a 3/4 length subsequent to rev/Gen2?)Any help is greatly appreciated.

author: frogblender
author_rank: Regular Contributor
timestamp: April 09, 2021, 03:33:44 am
content: ..OP here: and let me pre-empt all the wise-acres who passed 5th-grade math and who'll suggest "well, just take the average of the half and full, and you'll get 3/4!"... that won't cut the mustard: if I do that, and the skynet card doesn't fit into Facebook's latest T-800 server, Zukerburger himself will walk into my boss's office and kick her ass. And then she'll walk into my office and kick my ass. So in order to fend off the machete, I need to point to aspecthat defines 3/4-length (thus I was asking if anyone has the gen4 CEM).

author: maxkunes
author_rank: Newbie
timestamp: April 09, 2021, 05:24:07 am
content: I might have access to the PCIE CEM r3.Hope this helps. I've attached screenshot of attached the relevant page. 3/4 length is a thing.

author: frogblender
author_rank: Regular Contributor
timestamp: April 09, 2021, 01:46:42 pm
content: Much thanks to @maxkunes !PCIe cards of "three-quarter length" were not defined until r3.
Wurth power module question - Page 1
Forum section: electronics / projects

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: July 20, 2019, 12:36:33 pm
content: https://katalog.we-online.com/pm/datasheet/171021501.pdfCan someone tell me what to do with the SW pins on this device? The datasheet unhelpfully says to not connect these pins to other functions, the sample layout in the datasheet shows them all connected together, but the Wurth eval board shows them all floating.In any case they seem to be internally connected. It's frustrating to see a datasheet from 2016 that still isn't updated, or am I complaining too much?How about the bizarre layout guidelines for the ground splitting they recommend? Also not done on the eval board, everything is connected together.Anyone ever use these? What did you do? The module itself works very well on the eval board, my guess is to simply follow the board itself, SW pins all floating, all grounds in one plane.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 20, 2019, 02:08:03 pm
content: The SW note is dumb, yeah. Seems you'd want to tie them together with a pour, for thermal capacity, but to connect nothing else (unless of course you want to try some snubbing or damping, which they'll never suggest, but that's where you'd do it).The layout seems not inconsistent with the GND note; see that there's no other GND connections to the back side plane, so AGND is essentially tying to PGND at the point indicated. I don't see anything wrong with pouring copper over everything GND, top and bottom.Tim

author: capt bullshot
author_rank: Super Contributor
timestamp: July 20, 2019, 03:58:56 pm
content: Oh, another ugly Würth stuff -- thrown together an inductor (made by a company like Pulse or whatever they've bought) into a re-branded power module (check the usual suspects like LT for a similar one).
X-Link Bluetooth gateway and rotary wall phone project  - Page 1
Forum section: electronics / projects

author: gbkd80
author_rank: Newbie
timestamp: May 30, 2019, 11:03:34 pm
content: Hello- I am adding an old rotary wall phone in my kitchen (since I have a spot for it to go anyway) mostly for the retro look to match my theme- but once I realized they sell a Bluetooth gateway that would work on any phone, including the rotary, I said cool I’ll just use that. The idea is that I can bridge it from my cellphone and make it actually function since I don’t actually have an active land line.The conundrum is this: I don’t have a power outlet near the phone jack, and this gateway itself is a bit unsightly and large, and requires power. I tried to see if I could feed it down the wall with the existing land line wires but I had sheetrocked over that area of my basement back when I bought the house many years ago. So my idea of having the BT in the basement out of sight won’t work without extra work I don’t want to commit to. Then I thought about possibly taking the gateway apart and somehow mounting it inside the rotary phone; although I’d still need power. Maybe some sort of DC battery clip that I can mount on the side?Anyone ever play around with this stuff? I know it’s not really a ‘build’ but it’s a project I wanted to do :-)

author: zitt
author_rank: Regular Contributor
timestamp: June 03, 2019, 10:56:52 pm
content: So... it's P.O.T.S rotary phone... where the power is typically derived from the red and green wires; right?To power the rotary phone; don't you just plug into the RJ connector?If so; is there a spec on the BT device where you can't have a length of twisted pair to the Rotary phone?IE gateway in the "basement" and a short run of twisted pair to the rotary phone.What am I missing? Ah - you said you didn't want to run it to the basement.Still tho; a remote power plug with twisted pair running to the phone seems the easiest to do.

author: sokoloff
author_rank: Super Contributor
timestamp: June 03, 2019, 11:01:51 pm
content: As @zitt said, if you have two wires (they don't even have to be twisted; the very old ones weren't) from the BT to the phone, the phone will work. That opens up a lot of possibilities for where to hide the XLink. (You want it to be close by to where you leave/charge your phones, so the bluetooth works well.)Small sheetrock repairs are quite easy. I wouldn't hesitate to drill into the wall as needed to locate the XLink in a cabinet, over the microwave, or what have you. (We use an Xlink at home; it's nice. I didn't know until just now that it supports rotary dialing.)
x-microwave lego style biasing method - Page 1
Forum section: electronics / projects

author: john23
author_rank: Frequent Contributor
timestamp: July 18, 2025, 07:06:18 am
content: Hello,I have bought a PCB of an amplifier. The amplifier is like a lego.The problem with this is how do I bias it. I have rf_in rf_out But I dont know how to bias such things. What component do we use to deliver the DC into this amplifier component?Is there some examples? Thanks.https://www.analog.com/en/resources...o-prototype-rf-designs-using-x-microwave.htmlhttps://catalog.quanticxmw.com/item/x-mwblocks/amplifiers/XM-A9V6-0604D
X-Ray Control Grid Voltage - Page 1
Forum section: electronics / projects

author: sixtimesseven
author_rank: Frequent Contributor
timestamp: June 02, 2020, 04:05:25 pm
content: Does anyone know what typical X-Ray tube control grid voltages are?I have the datasheet for my Microfocus X-Ray tube (60kV, 1A, 50W) and it has grid control. However, no mention on the specific voltages. Does anyone know some typical values? I've seen some schematics with up to -10kV, that would be a real pain to supply.

author: Wolfram
author_rank: Frequent Contributor
timestamp: June 02, 2020, 10:29:19 pm
content: For similarly sized dental X-ray tubes, the focus voltage tends to be in the -600 - -800 V range.If you feel like experimenting, you can apply a variable voltage and see how the tube behaves. If you apply the maximum filament current and anode voltage, then you know the focus voltage is too negative if you don't get the rated anode current. You can also observe the focal spot with a lead pinhole and adjust the focus voltage to get the rated size. Beware that you might be able to focus the beam to a finer spot than the tube was designed for, resulting in excessive anode power density.Edit: found some info specific to your tube, see the attachment. It looks like your focal spot is in the first category, so the actual voltage doesn't matter much. You could possibly just tie it to the cathode through a resistor in case you want CW output. Source:https://www.yumpu.com/en/document/read/3917835/produktkatalog-pdf-66-mb-petrick-gmbh. Here's some additional data on a similar tube to yours as well:https://www.yumpu.com/en/document/read/3918040/1titel-112g6-epsd-petrick-gmbh

author: sixtimesseven
author_rank: Frequent Contributor
timestamp: June 02, 2020, 11:25:13 pm
content: Quote from: Wolfram on June 02, 2020, 10:29:19 pmLooks good. So far it worked even with the grid disconnected.My idea was to be able to turn of the tube to a.) limit x ray emission even though I have a pretty good lead box I still don't just want to pump it out and b.) limit heating of the focal spot when not in use c.) would be to be able to adjust something inside the box but I'm not certain I trust it fully since loss of negative voltage would turn it on again.As far as I understand the grid control is usually used to get a fast shutter to do xray "video". Might be fun as well.
X-ray detector Philips PW1965/20 DY1787 Geiger tube Teardown, info wanted ? - Page 1
Forum section: electronics / projects

author: oz2cpu
author_rank: Frequent Contributor
timestamp: March 22, 2022, 09:42:49 pm
content: any of you know anything about this unit ?On the case was written : PHILIPS PW 1965/20 DY1787so i guess PW means production week ? 1965 could be the year ?please tell more in the comments, if you know what the parts are..I am a bit out of my top expertice here...https://youtu.be/ZNZQkPB0wsE

author: jmelson
author_rank: Super Contributor
timestamp: March 22, 2022, 10:04:22 pm
content: This is part of an X-ray diffractometer set. The whole setup would have a "pencil beam" X-ray source, a crystal holder in the center, and an X-ray detector on a movable arm called a goniometer. In the old days, a piece of X-ray film was wrapped in an arc around the crystal, and a pattern of dark spots would appear when the film was developed. Later methods used a detector and electronic counters to replace the film. Even later systems had the goniometer computer-controlled so measurements could be taken at a range of angles.Jon

author: oz2cpu
author_rank: Frequent Contributor
timestamp: March 23, 2022, 09:31:15 am
content: thanks a lot jonfor all that informationi do consider to re visit the trash location, to see if i can find the xray source and its powersupplyi am allready halve way thru the next video filming : PORTABLE PROTON MAGNETOMETERalso a "thing" i know absolutly nothing about, cant even figure out what is the point in measure this type of magnetic field.

author: jmelson
author_rank: Super Contributor
timestamp: March 23, 2022, 04:36:37 pm
content: Quote from: oz2cpu on March 23, 2022, 09:31:15 amUmm, ever heard of medical MRI? It works by using magnetic field gradients to subtly change the natural precession frequency of protons in the water in the body. A pulse of RF excites the protons and then they create a weak radio frequency emission as they continue to precess.Jon

author: TimFox
author_rank: Super Contributor
timestamp: March 23, 2022, 06:55:07 pm
content: A small NMR spectrometer wrapped around a suitable liquid solution is used to measure external magnetic fields precisely, without the spatial encoding required for MRI imaging.When I was working in MRI, we used such a "magnetometer" to measure the homogeneity and magnitude of the large static magnetic field.
X-Ray effects on microcontrolers - Page 1
Forum section: electronics / projects

author: Amper
author_rank: Frequent Contributor
timestamp: February 26, 2020, 02:21:20 pm
content: Hi!Im currently working on a micro focus x-ray setup for various purposes around the hobby. One of the first very obvious things to have a look through is ICs, in particular micros and potted devices containing them. However nor im curious how much x-ray dose the program can handle and how much the chip it self can handle before destruction.My source is a repaired thermofisher psx5 micro focus head putting out 20-70keV and 0-200uA so im very well in the usual range for circuit board inspection machines, in fact the manufacturer lists it as a common application.Id be glad if someone working in this area could help me out a bit.
X-Ray high voltage power supply and grunding - Page 1
Forum section: electronics / projects

author: Neukyhm
author_rank: Contributor
timestamp: May 13, 2017, 04:46:55 pm
content: Hi there. I need help with a 70KV power supply I will build soon. The problem is that the cathode goes to the heated filament of the x-ray tube so x-rays are made. If I do this, I will have to build a small isolation transformer for the filament that runs with 2.5-3V. I will also have to isolate the Cockroft Walton multiplier and tube anode with epoxy, see diagram:(Note: the multiplier cathode goes from the beginning of the multiplier of course, I have drawn it wrong, corrected in next diagram)https://drive.google.com/file/d/0B4jpJVxcLvSEQWRTZXBFNFhzNDA/view?usp=sharing(Note: that resistor between filament and grid is required so emision won't be very high)But I asked for advice to the tube manufacturer and they said that if I ground the cathode, I will only have to isolate the multiplier and anode. This would be great because it means that I would be able to run the filament with any DC source, isolated or not, because the filament is connected to the cathode and this would be at 0V. See picture where I have added grounds.https://drive.google.com/file/d/0B4jpJVxcLvSEZThONkI4WVpzLUE/view?usp=sharingI want to build a C-W multiplier like my x-ray tube's manufacturer has:http://www.cei-xray.it/content/uploads/prodotto_image/ceiTrasformatorA3_1.pdfbut I'm not sure how I have to connect grounds, I mean, that square wave is coming from arduino, is it safe to connect arduino, primary coil and C-W multiplier grounds all together? This is the way that the manufacturer uses, and it is the best since you don't need insulation on cathode's side because it's grounded and at 0 volts.I have experience in HV and I have already built a X-Ray machine, but this "grounding method" is new to me, I don't even know if those grounds are well placed. So, you guys that are more experienced, please give me any advice you have.

author: james_s
author_rank: Super Contributor
timestamp: May 14, 2017, 04:17:23 am
content: None of your pictures work so I can't quite follow what you're trying to do.If you'd like to see how a commercial unit works, I reverse engineered one a number of years ago, schematic is available here:https://www.repairfaq.org/sam/xraysys.htm#xraytroKodak runs the cathode at ground potential and the anode at 70kV. It uses closed loop regulation using a divider to monitor the anode.

author: TimFox
author_rank: Super Contributor
timestamp: May 14, 2017, 09:08:11 pm
content: Grounding either the cathode or anode will work, with appropriate polarity. High-voltage tubes are often run with both electrodes at high potential (opposite polarity) to reduce the insulation requirement on the cables.Be sure to check that the insulation on the anode from ground or case is sufficient, if you ground the cathode. Also check how the electron current is measured and/or stabilized. If there is a sense resistor from (close to ground) anode to ground, be very careful about its accidental disconnection or failure.
X-ray image problem with CMDR-2ST Minxray - Page 1
Forum section: electronics / projects

author: kien2t
author_rank: Newbie
timestamp: January 23, 2018, 04:23:25 am
content: Hi all,I'm newbie, today i'm facing with a problem relate to x-ray image processing when exposed some positions like: skull, supine chest. i tried to change alot of parameters of equipemt as Kvp, mAs, focus spot... but nothing change. And when analyze the picture, have striped area that i cant explain what is it and in that area have a blurred zone.Have any one have experiences with this phenomenon and please let me some advice. Thank you so much !Regard!Kien

author: jopapeca
author_rank: Newbie
timestamp: January 24, 2018, 04:49:35 pm
content: HiIt looks to me that its a sensor problem.RegardsPauloEnviado do meu SM-G935F através do Tapatalk
X-Ray Machine for R & D Lab - Page 1
Forum section: electronics / projects

author: tarun172
author_rank: Regular Contributor
timestamp: March 12, 2017, 05:29:59 pm
content: Hi Guys,Last week, I came across a portable x-ray machine which I thought I have great use in my company's electronics R & D lab. I found few portable equipments on several websites but still not sure if that is one I need. I saw Dave's post from 2014. Does anybody have any experience using an X-Ray in United States? Are there laws restricting use of X-Ray machine in R & D labs in USA?- Tarun

author: TimFox
author_rank: Super Contributor
timestamp: March 12, 2017, 05:57:37 pm
content: Yes, there are laws governing such equipment. Technically, they vary by state, so you should inquire directly to the radiation-safety department (or their website) of the state where you intend to operate it. In Illinois, before I retired, we registered each x-ray set that we had installed in the laboratory (as opposed to those we built for sale and were temporarily in house) and had periodic visits from the state authority to verify safe operation and record-keeping. You may need to keep a calibrated radiation meter to check safe operation.

author: PointyOintment
author_rank: Frequent Contributor
timestamp: March 13, 2017, 07:24:11 am
content: Might be helpful:https://www.youtube.com/user/bkraz333/search?query=x-ray
X-ray of a Behlke high voltage transistor module - Page 1
Forum section: electronics / projects

author: daqq
author_rank: Super Contributor
timestamp: October 07, 2025, 12:04:17 pm
content: Hi,While X-raying our normal stuff I asked our supplier to X-ray a Behlke switch that I have. The results are in the attachment. No surprises I suppose, seems like a series-parallel connection of transistors, with a small transformer driving the gates on each 'level' or layer.Funny partDavid
X-Y output optical mouse sensor thingies - Page 1
Forum section: electronics / projects

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: October 22, 2023, 10:51:56 pm
content: Does anyone still make something like theBroadcomAvago ADNS-2051?https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/876/ADNS-2051.pdfWhat I like is" output format is two channel quadrature (X and Y direction) which emulates encoder photo-transistors."Like there's a lot of similar parts but are 20+ years old and obs/NLA.I can buy some from Aliexpress, but are there modern ones with X-Y output? Preferably standalone that power up in a usable state and doesn't need software configuration?Thanks!

author: Clear as mud
author_rank: Regular Contributor
timestamp: January 09, 2024, 03:38:40 pm
content: I don't see any after searching for a while. I'm a little surprised. They were still available about 3 years ago when I looked, but I guess the mouse manufacturers don't use them anymore.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: January 09, 2024, 06:25:10 pm
content: Quote from: Alex Eisenhut on October 22, 2023, 10:51:56 pmI am not surprised at all. It' simply not cost effective to use a separate uC to interpret quadrature signals and convert them to USB as is done for mice. Especially for penny pinching mass consumer products. And for a "high performance" / "gaming" mouse, cost is less of an issue, but the latency for extra conversion is not optimal.I think those things were a perfect example of a temporary solution for a shifting market, and it's been so long ago now that mice with balls have become obsolete that it's no surprise these chips are obsolete too.Maybe it's possible to find a chip that is able to generate quadrature outputs after you send some configuration bytes to it, but you'd have to search datasheets, or websites of manufacturers.

author: magic
author_rank: Super Contributor
timestamp: January 09, 2024, 07:24:52 pm
content: These days mice are integrated down to one chip which tracks the surface and talks USB to the host. More complex ones may use a SPI sensor and a USB MCU.If your MCU is USB host capable, you only need a host software stack with HID driver and you can use a mouse-on-chip
X10 Help - Page 1
Forum section: electronics / projects

author: Bryan
author_rank: Frequent Contributor
timestamp: October 31, 2024, 07:16:25 pm
content: All:Trying to put back into service a old X10 device and would appreciate any assistance users who are familiar with this old technology. Basically have a old aquarium controller that communicates with a X10 module PSC04/TW513? etc to put the signals onto the transmission line and subsequent modules decode the data and activate lights/sockets etc. What I want to do is intercept the output from the controller and send to a Arduino project to decipher the signals and activate various relays foregoing the legacy X10 modules.I am having difficulty getting the controller to send out any data on the data line to the scope and not sure what is wrong.I have perused the internet on the protocols, but they more or less describe how X10 works post controller and the X10 protocol. As I understand from any device to the X10 PSC04/TW513 module there are 2 ground wires, a data out and a zero-cross input. I only assume from what I have read that in order for the controller to start transmitting it needs to see a zero-cross on the applicable zero-cross line. I have tried injecting a 60hz 2volt sine wave/square wave into the zero-cross but nothing triggers the data out line to send any data.Any ideas what is wrong or how can get this to work. I don't see the amplitude of the square wave input being of importance as it would be looking for a zero-cross?Befuddled on next steps, as to how to trick the controller to send out the x10 commands, and I no longer have the PSC04 to test it. Could try building a isolated mains zero cross out and testing with that?

author: Doctorandus_P
author_rank: Super Contributor
timestamp: November 02, 2024, 02:47:32 pm
content: That zero crossing wire is probably designed to be connected to the mains voltage, and in that case, 2V is not going to make a big impression on it. So try a higher input voltage.A DIY method for a small isolation transformer is to put two identical transformers back to back.Another option is to use a function generator combined with an audio amplifier and a small mains transformer.

author: Bryan
author_rank: Frequent Contributor
timestamp: November 03, 2024, 09:12:51 am
content: Thanks for the reply, you could be right on that point. The controller is all 5 volt as far as I believe, so would be concerned about anything over 5V, but who knows if the inputs are attenuated. Will scour the net for some more information on the PSc04 controller and see if there are some specs on the zero cross amplitude. Must be around somewhere as OEM would need that info when designing their equipment.Here is a schematic for the controller. Any idea from the schematic what the zero detect voltage would be?. Hmm, the more I look at the schematic I wonder if I smoked the controller by supplying voltage as it looks like there is no voltage supplied.
x100 Gen Purpose Amp for lab use, 1st attempt. - Page 1
Forum section: electronics / projects

author: Insatman
author_rank: Frequent Contributor
timestamp: February 20, 2018, 04:39:44 am
content: Hello, I set about building an x100 amplifier mainly to measure noise on power supplies where my scope runs into the noise floor. This is my first attempt. Bandwidth is -3dB at 185kHz. I hope to improve this by using a better op-amp on order from Digikey. Noise floor with the input terminated 50ohm is about 2mV pk-pk. This could be general noise from my lab, the scope or the cheap cable I used as well as the op-amp. Nevertheless, this equates to roughly 20uV on the input, meaning the amp is only useful for ~100uV of noise or above without averaging. A low-pass filter of ~90kHz was built into the unit and can be switched in and out using a toggle switch. The filter is an active type using two sections of the quad-op-amp. The noise floor is significantly higher when the filter in on, which surprised me. I intend to play with the circuit and see if this can be improved. Your comments, questions and advice are solicited.

author: PartialDischarge
author_rank: Super Contributor
timestamp: February 20, 2018, 06:21:50 am
content: Very nice project. For this application im fortunate enough to own a 7104 with a 7A22 plugin

author: Insatman
author_rank: Frequent Contributor
timestamp: February 20, 2018, 07:12:59 am
content: Quote from: MasterTech on February 20, 2018, 06:21:50 amAhh...I remember using a 7104 when they first came out early in my career. We had 7A22s as well but didn't use them much because of the type of work we were doing. The micro-channel plate CRT was great for capturing fast pulses on film back in the day.