Electrical Engineering V3 - Developers

not as simple as i thought [img]http://i.imgur.com/CCm9Q8T.png[/img]

It's amazing how you think you understand the basics of electricity and when you start your degree coursework suddenly nothing makes sense. Like ohm's law was great but now we're solving circuits that make no physical sense. [sp]we're only doing basic nodal analysis and it takes me fifteen minutes to solve simple circuits send help please[/sp]

[QUOTE=papkee;51022984]It's amazing how you think you understand the basics of electricity and when you start your degree coursework suddenly nothing makes sense. Like ohm's law was great but now we're solving circuits that make no physical sense. [sp]we're only doing basic nodal analysis and it takes me fifteen minutes to solve simple circuits send help please[/sp][/QUOTE] Send example please? :p

[QUOTE=LoneWolf_Recon;51021712]I've been working on this for awhile, it was a pain in the butt to find a transformerless EL driver that can drive up to a foot of EL Wire. Costuming/Gaming Controller Glove! [video=youtube;X0YdSWUp4qo]http://www.youtube.com/watch?v=X0YdSWUp4qo[/video][/QUOTE] Gloves like these are sorcery. See how far you can take it, maybe it'll end like [URL="http://www.washington.edu/news/2016/04/12/uw-undergraduate-team-wins-10000-lemelson-mit-student-prize-for-gloves-that-translate-sign-language/"]this[/URL] [also this one of the kids that was rejected from aero like I was, wtf he literally made uni headlines]

[QUOTE=papkee;51022984]It's amazing how you think you understand the basics of electricity and when you start your degree coursework suddenly nothing makes sense. Like ohm's law was great but now we're solving circuits that make no physical sense. [sp]we're only doing basic nodal analysis and it takes me fifteen minutes to solve simple circuits send help please[/sp][/QUOTE] hey i'm also doing that in my circuits class! i enjoy it. it's like a big fun puzzle

First time I tried learning about nontrivial DC circuit analysis I got destroyed. Nothing made any sense at all. Saw it again once I actually got to college and it clicked quite a bit more. I'd bet the one teaching it is the difference between the class making any scrap of sense or not. You're being given circuits that don't make any physical sense mostly because in the future, you can approximate a part as a simple passive circuit element, but that doesn't guarantee that it's going to look pretty. AC circuits are hellspawn though, you use the same nodal/mesh analysis, except this time you use impedances, which behave like imaginary resistances so the algebra all just goes to shit. You don't have to do that stuff later on though, I just took a class in diodes and FETs and we were given very simple circuits, although that was made up for by the I-V characteristics being a nightmare. [QUOTE=paindoc;51024851] [also this one of the kids that was rejected from aero like I was, wtf he literally made uni headlines][/QUOTE] He actually just got in after appealing the decision [i]twice[/i]. I love this university.

hello, I came here to ask for some advice on a power supply. I recently bought [URL="http://www.ebay.com/itm/231105154168?var=530282534039"]this[/URL], a 5v 5M WS2812B strip of LEDs, and I was a bit too quick in buying it because I didn't consider finding a power supply a problem. So I'm having trouble finding a large enough one that is wall-plugged (20 amp, 5v, according to my (probably incorrect) amateur calculations), i don't know if it's insane to even try to power the whole thing? or should I just cut it to a shorter length (around 2/2.5m) and find a suitable lower amp supply?

[QUOTE=Syntox;51030395]hello, I came here to ask for some advice on a power supply. I recently bought [URL="http://www.ebay.com/itm/231105154168?var=530282534039"]this[/URL], a 5v 5M WS2812B strip of LEDs, and I was a bit too quick in buying it because I didn't consider finding a power supply a problem. So I'm having trouble finding a large enough one that is wall-plugged (20 amp, 5v, according to my (probably incorrect) amateur calculations), i don't know if it's insane to even try to power the whole thing? or should I just cut it to a shorter length (around 2/2.5m) and find a suitable lower amp supply?[/QUOTE] 5V 20A sounds like power-brick territory rather than a wall-wart. Alternatively, if size/noise isn't a factor, an old ATX PSU should be able to provide more than enough amperage on the 5V rail. (the little tiny old Dell PSU I use for most of my current tinkering provides up to 13A, and it's only a 205W-max supply) Also, my 30 high-torque metal-gear servos came in today. :dance: [media]https://www.youtube.com/watch?v=Ci9CCvTHvpM[/media]

[QUOTE=Syntox;51030395]hello, I came here to ask for some advice on a power supply. I recently bought [URL="http://www.ebay.com/itm/231105154168?var=530282534039"]this[/URL], a 5v 5M WS2812B strip of LEDs, and I was a bit too quick in buying it because I didn't consider finding a power supply a problem. So I'm having trouble finding a large enough one that is wall-plugged (20 amp, 5v, according to my (probably incorrect) amateur calculations), i don't know if it's insane to even try to power the whole thing? or should I just cut it to a shorter length (around 2/2.5m) and find a suitable lower amp supply?[/QUOTE] In my opinion, you should split the strips into two, three or four separate strips (But you can still daisy chain data lines). This is more to due with the amount of waste heat that'd be generated if kept it as a single strand from the traces attempting to carry 20A of current across the entire strip. You'll be hard pressed to find a 5V wall wart that supplies more than 2A. IMO, you should stick with a ATX supply or [URL="https://www.amazon.com/Regulated-Switch-Power-Supply-Adapter/dp/B008DFCM6Y"]similar 5V switching supply[/URL], try to hide them somewhere inconspicuous, tie the grounds together and have separate 5V and GND wires going to each strip.

[QUOTE=Zero-Point;51030438]5V 20A sounds like power-brick territory rather than a wall-wart.[/QUOTE] So far the ones I've found looked like cheap PC power-supplies, so I sort of had in mind it wouldn't be too low-profile, but hoped I would find something which didn't look too "exposed" [B]edit:[/B] [QUOTE=LoneWolf_Recon;51030463]In my opinion, you should split the strips into two, three or four separate strips (But you can still daisy chain data lines). This is more to due with the amount of waste heat that'd be generated if kept it as a single strand from the traces attempting to carry 20A of current across the entire strip. You'll be hard pressed to find a 5V wall wart that supplies more than 2A. IMO, you should stick with a ATX supply or [URL="https://www.amazon.com/Regulated-Switch-Power-Supply-Adapter/dp/B008DFCM6Y"]similar 5V switching supply[/URL], try to hide them somewhere inconspicuous, tie the grounds together and have separate 5V and GND wires going to each strip.[/QUOTE] So I could split them up in say two to three pieces and use that type of ATX supply for each of them, so long they have common ground? and if I were to say connect the data wires from an arduino, would I have to wire the ground between the power-supply and the arduino, togheter?

[QUOTE=Syntox;51030468]So far the ones I've found looked like cheap PC power-supplies, so I sort of had in mind it wouldn't be too low-profile, but hoped I would find something which didn't look too "exposed" [B]edit:[/B] So I could split them up in say two to three pieces and use that type of ATX supply for each of them, so long they have common ground? and if I were to say connect the data wires from an arduino, would I have to wire the ground between the power-supply and the arduino, togheter?[/QUOTE] [url]http://www.ebay.com/itm/AC110-220V-TO-DC-5V-12V-24V-Switch-Power-Supply-Driver-adapter-For-LED-Strip-/272083459548?var=&hash=item3f59701ddc:m:mbxc8bdL9OLyUUYFbkfenFA[/url] <- 5V 20A supply that costs $20. Or hell, if you want to over-engineer it, here's one that has more ampacity and is only a few dollars more: [url]http://www.ebay.com/itm/AC110-220V-TO-DC-48V-24V-12V-5V-Switch-Power-Supply-Driver-Adapter-For-LED-Strip-/371514993202?var=&hash=item568004ea32:m:m-Tt3_1c6P79IZt8SZqzWPw[/url] As for the ground, yes. Ground provides a common reference point.

[QUOTE=Zero-Point;51030526][url]http://www.ebay.com/itm/AC110-220V-TO-DC-5V-12V-24V-Switch-Power-Supply-Driver-adapter-For-LED-Strip-/272083459548?var=&hash=item3f59701ddc:m:mbxc8bdL9OLyUUYFbkfenFA[/url] <- 5V 20A supply that costs $20. Or hell, if you want to over-engineer it, here's one that has more ampacity and is only a few dollars more: [url]http://www.ebay.com/itm/AC110-220V-TO-DC-48V-24V-12V-5V-Switch-Power-Supply-Driver-Adapter-For-LED-Strip-/371514993202?var=&hash=item568004ea32:m:m-Tt3_1c6P79IZt8SZqzWPw[/url] As for the ground, yes. Ground provides a common reference point.[/QUOTE] alright, thanks for all the help guys. I'll split the strip up into two pieces and try to power them separately with two 5v 10 amp, with common data lines (and ground)

anyone proficient in verilog want to go over my code and see why i'm getting a malformed statement error?

I'm vaguely proficient, some of the others are much better. If you post the code in [code] tags we'll all be able to look at it.

i'm gonna post it in an unlisted pastebin [url]http://pastebin.com/Jbxf4GnG[/url] excuse the shitty code. i was trying a few things before giving up for the night so there might be more errors and weird roundabout things. also i haven't programmed verilog in a year i'm designing the thing i described a few posts up. a thing that averages two 8 bit unsigned ints without using any operators and also rounds up. the main modules that i have are the averager that i'm building, a reference averager using operators, and a test bench to compare the two modules. the general flow of the module is: 1. take in two 8 bit inputs 2. add using a ripple carry adder 3. check if the sum is odd (LMB is 1). if so round up by adding 1 4. shift bits right by 1 to divide by 2 5. output i get the malformed statement on line 58 [editline]12th September 2016[/editline] figured it out. i was calling modules the wrong way

I'm glad you figured out your problem! Could I suggest something? Since you are always shifting off the LSB anyway, you can just unconditionally add the 1, and I believe rounding will occur as you intend. The easiest way to do this is to have a carry in to your 8 bit adder (you're currently just tying off the least significant full-adder carry in to 0 I think) and set that to one. This also lets you e.g. build bigger adders from 8 bit adders, and will synth to the same hardware if you just tie off the carry-in at the next module up. This removes most of your "rounder" module, and any need for the 9-bit adder.

i didn't think about that! that's actually pretty clever. thanks! [editline]12th September 2016[/editline] [img]https://dl.dropboxusercontent.com/u/5168294/ShareX/2016/09/chrome_2016-09-12_23-36-55.png[/img] eyyyyyyyyyyyyyyyyyyyy

Snip

[img]http://i11.photobucket.com/albums/a166/ballsandy/Computer%20related/IMG_5893.jpg[/img] That's a retrofit I thought would take way more effort than I thought it would be. The guts of an NEC panel were either removed or rearranged so the digital board from another monitor could be installed. The one input cable supplies power and video as well as sound, microphone, keyboard and mouse data.

That CPT brick brings back good memories. Five years ago one of the first projects I ever did involved one of those to step down 12v vehicle power to 5v for an arduino system. Man, that seems like so long ago. Also please give more context. I want to know what the hell you're talking about because it sounds like something I would do.

I'm gonna have to get me several of those CPT supplies, [URL="http://www.current-logic.com/dcdc_converter_car.php"]their site[/URL] has options for microUSB output while being IP67 rated.

[QUOTE=papkee;51068418] Also please give more context. I want to know what the hell you're talking about because it sounds like something I would do.[/QUOTE] Okay, so NeXT Computers sold as the main monitor for their systems a high resolution monochrome monitor called the Megapixel Display. You plug one cable in from the computer and that powered the monitor but also carried the data lines for the keyboard and mouse, PLUS the audio I/O. [img]http://www.blackholeinc.com/store/images/cache/NeXTmonitorMono.580.png[/img] [img]http://www.iproweb.fr/test/1%20-%20PETIT%20BUREAU/NeXTstation%20MegaPixel%20Display%20N4000A/IMG_4660.JPG[/img] The problem is that these have no concept of energy savings. Sure the screen dimmed after a while to prevent burn-in but the CRT never turned off so a monitor that might be in excellent shape might have tens of thousands of hours on it which means the cathode is dead. Some people dispose of the whole monitor at that point and opt for VGA mods but my idea was to take the digital guts out of the monitor and mount it in an LCD. [url=http://hackaday.com/2014/12/27/next-cubes-and-lcd-monitors/]Someone more recently did the same thing[/url] and I was curious if I could make it work as well on another model monitor while cleaning up the mess of cabling he had made inside. I only chose to use a CPT because my 7805's are only rated to 1A whereas these are rated for 2.

So let's say I have a fluorescent bulb in a paper scanner head assembly and I want that bulb to only light up when the scanner motor is moving. I've already interfaced with the motor directly and I plan on using signals from my interface to tell the light when to turn on. As far as I can tell the bulb runs on 24v or more. The driver it was connected to has 24v in, but the driver looks like it's a boost converter because there's a pretty huge transformer on it. I do not have a variable supply at the moment so I'm waiting on a 12v - 24v boost converter to arrive so I can at least try to power it on. Now to my question. I know I can't just wire the signal and power line together. I know I'll need a transistor between the supply to the bulb and the signal I want to use to run the light. Basically the motor signal flipping the transistor off allowing power to flow through to the bulb. However I've never really messed with transistors before. I know what they do but I do not know what kind of transistor I would need. From the research I've done it seems there's MANY. Would I need one that operates on the same output voltage? I read that some of them are current based so needing a specific voltage doesn't matter, but I have no idea what kind of current rating I'd need. I haven't been able to track down any datasheets on any of this stuff. Is going too high with the rating dangerous or can I just get a transistor with an obscene current rating? What type of transistor would be best suited to this task? Edit Signal voltage that I'll be using peaks at 2.5v. Edit 2 My boost converter arrived and it sadly did not power the lamp just out of the box and hooking things up to obvious spots. I probed around the driver the lamp was originally connected to and followed the voltage trail. It stopped at a transistor so I tried bridging two of the pins. The light turned on. I then removed the bridge and touched the signal from my arduino to it and it pulses with every signal. Awesome!

I have a question, is it easy and affordable to print a PCB of a schematic with parts on it? (From like china or something) I need to make quite alot of guitar pedals and now I have to wire everything together myself with a stripboard, if the price difference isn't too much I can just order it. [img]http://i.imgur.com/C3sJlqh.png[/img] This being one of the schematics, they are quite simple.

[QUOTE=Staneh;51099514]I have a question, is it easy and affordable to print a PCB of a schematic with parts on it? (From like china or something) I need to make quite alot of guitar pedals and now I have to wire everything together myself with a stripboard, if the price difference isn't too much I can just order it. [img]http://i.imgur.com/C3sJlqh.png[/img] This being one of the schematics, they are quite simple.[/QUOTE] ~20$ for 10 boards, including slow shipping.

[QUOTE=DrDevil;51099697]~20$ for 10 boards, including slow shipping.[/QUOTE] With components or without?

[QUOTE=Staneh;51099775]With components or without?[/QUOTE] Without. IF assembled in china, then it's probably cheaper to use SMD components.

[QUOTE=Van-man;51099839]Without. IF assembled in china, then it's probably cheaper to use SMD components.[/QUOTE] Do you know how much it would cost with components? I could also PM if you'd prefer that

It really depends on the volume you're going for and the components you're going to use, but I'd guess that the components for a single board would cost something around a buck or two without assembly.

Do you know the estimate cost for assembly all together? Sorry for asking so many questions :v: