|
I think it's for medical applications? Also, check craigslist and fb marketplace before ebay when shopping for isolation transformers. Heavy + obscure = buyer's market. The shipping cost hurts when they try to sell on ebay.
|
#
?
Jul 24, 2023 02:44
|
|
|
|
| # ? May 22, 2024 12:58 |
|
|
I do have an isolation transformer, for a project that I kinda stalled out on, due to other things. But I will get back on it some day. In the meantime I guess I will just try it with the 10x probes. Does feel like a good idea to keep a lookout for 2nd hand differential probes though. This donut style one, 1000VA  Was gonna hook it up with this autotransformer in a single box. I had schematics and everything made when I stalled out on it.  His Divine Shadow fucked around with this message at 04:19 on Jul 24, 2023 |
|
#
?
Jul 24, 2023 04:16
|
|
|
All this talk of isolation transformers made me think of one of my favorite facts about old radios. Before permanent magnets were invented, radios used electromagnets in their speakers. We take for granted how far we've come.
|
|
#
?
Jul 25, 2023 01:20
|
|
|
kid sinister posted:All this talk of isolation transformers made me think of one of my favorite facts about old radios. Before permanent magnets were invented, radios used electromagnets in their speakers. We take for granted how far we've come.  i had never really thought about the fact that basically all magnets are manufactured. I have a question though! I'm looking at building a demonstration of a generator. The idea is that a bellows blows air across a little anemometer, and the spinning powers a little light. I figure a little RC motor or something could probably act as the generator here, but I'm not sure where to start. I'd like something small enough to fit in one hand. What kind of specs should I be looking for?
|
|
#
?
Jul 25, 2023 23:11
|
|
|
I mean they're wrong, artificial permanent magnets were invented long before electromagnets, but the magnet formulations of the time meant you either needed a goddamn massive permanent magnet or an electromagnet.
|
|
#
?
Jul 25, 2023 23:17
|
|
|
Anyway here's exactly what you're describing for ten bux: https://www.amazon.com/0-1V-5-5V-100-6000RPM-Vertical-Turbines-Generator/dp/B07HRGPFMD/ It's much more fun to build your own imo but this is at least a good example of the kind of motor you'd need (as in, just a normal-rear end tiny DC motor is fine, like you guessed)
|
|
#
?
Jul 25, 2023 23:20
|
|
|
Fanged Lawn Wormy posted:
There’s magnets in the earth. Like what compasses point at.
|
|
#
?
Jul 25, 2023 23:21
|
|
|
also just actual magnets https://en.wikipedia.org/wiki/Lodestone
|
|
#
?
Jul 25, 2023 23:25
|
|
|
eddiewalker posted:There’s magnets in the earth. Like what compasses point at. Fun fact: in the 1500's - 1600's it was assumed that compasses did that because at the north pole there was just a big ol' lump of magnetite 30 miles wide sitting on an island up there. Like they even drew it on old maps and everything.
|
|
#
?
Jul 25, 2023 23:26
|
|
|
Shame Boy posted:Fun fact: in the 1500's - 1600's it was assumed that compasses did that because at the north pole there was just a big ol' lump of magnetite 30 miles wide sitting on an island up there. Like they even drew it on old maps and everything. For a while people thought that the Earth's magnetic field was constant and invariant everywhere. Faraday attempted to define the idea of an electric current in relation to that field. The terms anode and cathode come from the connections he used that were located to the east (anode) or west (cathode) side a coil that would produce a magnetic field of the same strength and direction as the Earth's. https://en.wikipedia.org/wiki/Anode#Etymology https://en.wikipedia.org/wiki/Cathode#Etymology
|
|
#
?
Jul 26, 2023 00:11
|
|
|
PDP-1 posted:For a while people thought that the Earth's magnetic field was constant and invariant everywhere. Faraday attempted to define the idea of an electric current in relation to that field. The terms anode and cathode come from the connections he used that were located to the east (anode) or west (cathode) side a coil that would produce a magnetic field of the same strength and direction as the Earth's. I swear I told that exact story in here, and how he originally wanted to call it like "westode", but I guess that was actually the physics thread. Still pretty interesting.
|
|
#
?
Jul 26, 2023 00:17
|
|
|
Sometimes I think it would be funny to go back in time to those old scientists (the TOS era) and laugh at them for how dumb they are. But then I'd look dumb because they are the leading scientists of the era and I don't remember any of the math to back myself up.
|
|
#
?
Jul 26, 2023 00:44
|
|
|
Sagebrush posted:also just actual magnets ok so maybe I oversimplified a bit here, but for the most part, any magnet I'm coming in contact with day-to-day was manufactured. Shame Boy posted:Anyway here's exactly what you're describing for ten bux: I'll probably build my own propeller, but yeah, this is what I'm lookin' for!
|
|
#
?
Jul 26, 2023 16:55
|
|
|
I suppose I should have said practical permanent magnets.
|
|
#
?
Jul 26, 2023 18:08
|
|
|
Sorry if this isn't the best thread for this but I don't know what would be. I have a wood desk with a couple monitors on it, and a blanket folded on one end of the desk where my cat sits: https://i.imgur.com/g9b5kNH.mp4 My place is pretty dry/staticy and both monitors are prone to turning off momentarily when I get up from my chair too quick, touch my keyboard sometimes (metal case kb), etc. My cat also can cause the closer of the 2 monitors to turn off for a second just by standing up and laying back down. Is there anything I can do about this? I was thinking like a grounding mat under her blanket but I dunno if this is EMI and whether I would need to be like shielding my monitor from the cat on a line of sight type of basis (impossible) instead. e: I should add everything is sitting on hardwood floors and everything is grounded through mains. This is a condo less than 25 years old. VelociBacon fucked around with this message at 21:59 on Jul 27, 2023 |
|
#
?
Jul 27, 2023 21:54
|
|
|
It is a common problem; DisplayPort cables are particularly sensitive to it but HDMI can be affected too. https://vimeo.com/116294168 I would try swapping the monitor cables for some that are better shielded. In particular, hybrid optical cables are a little pricier at $50-ish but their data pins are converted to laser light so I would expect them to be more resilient: https://www.amazon.com/Pure-Fi-DisplayPort-Active-Optical/dp/B0BW5M677G/ If that doesn't fix it and you're not particularly in love with your keyboard, there's a billion varieties of Logitech Unifying that would let you run a keyboard and wireless mouse on a single USB dongle. I'm currently typing on this: https://www.amazon.com/Logitech-Multi-Device-Wireless-Certified-Refurbished/dp/B079F68RPZ/ edit: Here's some optical HDMI cables at $20 each, much more reasonable: https://www.amazon.com/Optic-Cable-Conbeer-Speed-18Gbs/dp/B07ZFDSWFF/ Zero VGS fucked around with this message at 22:41 on Jul 27, 2023 |
|
#
?
Jul 27, 2023 22:37
|
|
|
Raising the humidity in your room could help too
|
|
#
?
Jul 27, 2023 23:33
|
|
|
Zero VGS posted:It is a common problem; DisplayPort cables are particularly sensitive to it but HDMI can be affected too. Thank you, that's an interesting solution and I appreciate you finding some other cables - I'm in Canada so I'll take a look on Canadian amazon. I'm running a 4k144hz HDR monitor and I'm not certain that these cables can always push the required data rates. Okay actually just picked this one up: https://www.amazon.ca/gp/product/B09KZ435N6/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1. There's a review saying they're using it with my monitor at 144hz so that's promising. We'll see! I kinda figured the issue was the monitor electronics getting a static shock and not the cable but doesn't hurt with free returns to check. Splode posted:Raising the humidity in your room could help too It's 26C, 41% relative humidity in my room right now (Vancouver Canada), it gets down to the mid-20%s in the winter when it's dry. I do have a humidifier but it lives in the living room and honestly it needs filling with water so often that I have essentially stopped using it.
|
|
#
?
Jul 28, 2023 01:38
|
|
|
Put the cat in an antistatic bag
|
|
#
?
Jul 28, 2023 02:00
|
|
|
VelociBacon posted:Thank you, that's an interesting solution and I appreciate you finding some other cables - I'm in Canada so I'll take a look on Canadian amazon. I'm running a 4k144hz HDR monitor and I'm not certain that these cables can always push the required data rates. Yeah any optical cable that says it can do 4K 120hz, should be fine for 4K 144hz. The chips that are mass-produced for those from different generations, have bandwidth gigabit/second breakpoints where they are a little better than 4K30, 4K60, or 4K144.
|
|
#
?
Jul 28, 2023 02:38
|
|
|
Zero VGS posted:Yeah any optical cable that says it can do 4K 120hz, should be fine for 4K 144hz. The chips that are mass-produced for those from different generations, have bandwidth gigabit/second breakpoints where they are a little better than 4K30, 4K60, or 4K144. Yeah I double checked the throughput before I ordered. I'll report back with whether or not it did anything!
|
|
#
?
Jul 28, 2023 03:28
|
|
|
I'm thinking about attempting one of those DIY LED cube things, specifically this one. Just wondering if anyone has done anything like it and if there's anything I should be looking out for. The instructions are both extremely detailed and also frustratingly vague in some areas. I figured I would just start working on it and some things make more sense when I can actually see it. A Proper Uppercut fucked around with this message at 14:23 on Jul 29, 2023 |
|
#
?
Jul 28, 2023 20:45
|
|
|
A Proper Uppercut posted:The instructions are both extremely detailed and also frustratingly vague in some areas. I figured I would just start working on it and some things make more sense when I can actually see it. I think people here will offer plenty of help if you run into problems, but few will want to read through a 72 step instructable, goddamn. Is there a particular vague bit you are wondering about? Please specify the step #, page, and volume so I can find it. (this is not a dig at you, OP. but that web page is long as hell)
|
|
#
?
Jul 28, 2023 22:47
|
|
|
You could also make a 3x3x3 cube to understand how it works before investing a bunch of time and money into 8x8x8 version. That would have 27 LEDs and need 12 digital IO pins, you could build it in one evening and drive it off an Arduino Uno with no extra hardware.
|
|
#
?
Jul 28, 2023 22:54
|
|
|
That is a good idea. Get a solid understanding of the circuit and theory first. Then when you make the 8x8x8 display, you can focus 100% on the physical construction. There's also the phenomenon, I don't know if it has a name, where if you build some big 2D or 3D pattern with no practice, the first layer or first row will look obviously sloppy compared to later rows where you'd had a little practice. I've definitely built projects where that effect was evident. e: OP's real dilemma - build huge 8x8x8 circuit that comes with comprehensive instructions - build much smaller 3x3x3 circuit but need to improvise and adapt the design yourself It's unclear to me which path is easier. I suppose it depends on OP's skill level. ryanrs fucked around with this message at 23:14 on Jul 28, 2023 |
|
#
?
Jul 28, 2023 23:04
|
|
|
Somebody uploaded a bunch of digitized copies of Electronic Design magazine going back to 1966. The oldest volume contains an article theorizing about how someday it may be possible to put an entire computer on one chip. Also a bunch of nifty ads, it's surprising how many of these companies are still around. 
|
|
#
?
Jul 28, 2023 23:39
|
|
|
Cool, thanks! Also the first article on the first one I clicked from 1966 starts: "The downtrend in the industry's growth rate is being stemmed. Tactical-warfare equipment and industrial and consumer electronics are on the way up."  e: Why can't modern test equipment have fuckin' cogs and chain drives: 
Shame Boy fucked around with this message at 23:48 on Jul 28, 2023 |
|
#
?
Jul 28, 2023 23:44
|
|
|
ryanrs posted:That is a good idea. Get a solid understanding of the circuit and theory first. Then when you make the 8x8x8 display, you can focus 100% on the physical construction. There's a lot of "I don't know what I don't know" going on. I've had some good practice soldering and am a machinist by trade so I tend to be meticulous so I think I'll be okay building it. It's the controller and power that really intimidates me. I guess I'm hoping that as I make my way through things will start to click a little more. There are also kits on eBay and amazon that you build and the controller is already all set so I'm also considering one of those. Either way I think I'd rather go big or go home.
|
|
#
?
Jul 29, 2023 14:22
|
|
|
You could try buying a solderless breadboard and some pre-formed jumper wires to prototype your controller board instead of going directly to a hard soldered version like they do in the Instructable. That would let you easily test your design and modify it in chunks while you go through the learning phase. For example, learn to control one shift register, then how to chain two of them together. Once you can do that chaining eight of them is just repetition and that part of the circuit is ready to go off the breadboard and into a permanent form inside your project. Then start on the transistor low-side drivers, etc. Also, how comfortable are you at programming? The Instructable shows how to build up the controller from a bare metal microcontroller but if you instead use something from the Arduino family you'd have a nice IDE, you wouldn't need a stand-alone programmer, and it would just take a lot of work and risk out of the project. I noticed that they even had a version with an Arduino controller toward the end of the writeup.
|
|
#
?
Jul 29, 2023 15:03
|
|
|
Thanks to folks who recommended the Pinecil; it's a badass soldering iron that has handled everything my newbie self has tried with it. I'm not designing my own stuff (yet?), but it's been a real asset for repairs of things. It's helped me fix and upgrade the lovely stock fan on my 3d Printer, and I fixed a dead g600 mouse this weekend by de-soldering the busted left button switch and replacing it with a new one I got from Digikey. Total cost: like $3 and maybe some lead fumes inhaled?
|
|
#
?
Jul 31, 2023 02:44
|
|
|
Jedi425 posted:Thanks to folks who recommended the Pinecil; it's a badass soldering iron that has handled everything my newbie self has tried with it. Lead's partial pressure is too low to ever inhale appreciable amounts from soldering, what you're actually inhaling is rosin fumes which are probably still bad for you but in their own way.
|
|
#
?
Jul 31, 2023 02:50
|
|
|
Rosin fumes are, as far as I know, only an acute irritant. You might get a sore throat from breathing the stuff all day, but when you stop it'll go away and there won't be any permanent effects. Lead fumes are the exact opposite! Few or no immediate effects, long-term permanent brain damage.
|
|
#
?
Jul 31, 2023 03:01
|
|
|
Sagebrush posted:Rosin fumes are, as far as I know, only an acute irritant. You might get a sore throat from breathing the stuff all day, but when you stop it'll go away and there won't be any permanent effects. That's generally volatile lead compounds, not lead itself. I mean unless you're over a vat of boiling metal in which case you're soldering wrong.
|
|
#
?
Jul 31, 2023 03:15
|
|
|
There was one week where I did a lot of soldering and shooting, so I decided to get a blood test. I didn't think I had any significant exposure, but it seemed a good time to do lead screening. The nurse at Stanford Hospital had some intense questions aimed at determining if this was a workplace exposure, because that triggers a lot of OSHA stuff or something. Result was no detectable lead in my blood. So my common-sense/half-rear end precautions (like washing my hands) is enough for the kinds of activities I do. re rosin: the weed smokers are huffing way more terpenes than you, and they don't appear to be dying of cancer or w/e
|
|
#
?
Jul 31, 2023 03:17
|
|
|
I understand that lead exposure is also a less serious issue for adults than it is for children, because children's brains are still growing, and the amount of lead required to mess up that process is much less than what is required to cause noticeable effects in a fully grown brain. Now me, I started soldering at age 7, and
|
|
#
?
Jul 31, 2023 03:41
|
|
|
Sagebrush posted:I understand that lead exposure is also a less serious issue for adults than it is for children, because children's brains are still growing, and the amount of lead required to mess up that process is much less than what is required to cause noticeable effects in a fully grown brain. I started earlier than that and I turned out gay as hell, definitely related.
|
|
#
?
Jul 31, 2023 03:53
|
|
|
Sagebrush posted:Pum uctolchaxact zaxat roaxad oxpesulo dis axarse pit ropt solieus dissuo bel axadurts zaxan dit dis bel stirdlon, focaxauso stirdlon nud flaxains axalo chirr klewick, pi zo axameunk eb roaxad loquilow te vopt an zaxat plecopt dis vust ropt zaxan haxat dis loquilow te caxauso jeticoaxafro obbonds din pit burrupp klewn flaxain. Uh, ok
|
|
#
?
Jul 31, 2023 03:54
|
|
|
Rosin fumes are actually a genuine danger if you solder a lot. Chronic exposure will cause asthma. Back in the day it was not a question but a given that electronics factory workers working with rosin, would eventually get asthma. Most people won't be soldering countless hours a week, so for most the risk is very low. Since i landed a job at which i solder a couple of hours a week, as well as doing it a couple hours at home, i've been using proper precautions at home and at work. Ideally you feed the fumes outdoors, but in a pinch an activated carbon filter like the one used in recirculating cooker hoods will work pretty well. At home, my air filter instantly shoots to maximum about 30 seconds after touching a bit of solder to my soldering iron. The particulates of vaporized rosin spread quickly.
|
|
#
?
Jul 31, 2023 09:40
|
|
|
Huh, I had not heard of that. Everyone always talks about the lead.
|
|
#
?
Jul 31, 2023 16:55
|
|
|
|
| # ? May 22, 2024 12:58 |
|
|
Yeah the lead feels scary because it is more commonly known and it’s effects at so bad, but it generally isn’t airborne as many others have said. Rosin though, yeah. When we moved into our new office, I had a large job where I had to build some led Strip light panels -I soldered about 6-8 hours a day for a week straight. Previously, I would have done this on our main shop floor, but I used the workbench in the front area of the office space because it was air conditioned and has way less dust. I had some minor respiratory issues by the end of the week. I have mild asthma, and I could tell it was irritated from the work. Cleared up a few days later. We havent had a project that required that much soldering in a long time, but if we do again, we’re either doing it out on the big shop floor with all the fans and high ceilings, or we’re ventilating the space to protect our lungs.
|
|
#
?
Jul 31, 2023 17:38
|
|