Electrical Engineering V3 - Developers

I'm testing how well vinegar+hydrogen peroxide+salt eats copper away. Spoiler alert, it does, slowly. [t]https://i.imgur.com/JD20c9y.jpg[/t] If I care enough tomorrow, maybe I'll try to transfer a design to some copper, and try and etch a board.

I like my ferric chloride, mucky but it gets the job done.

I've got my pick of muriatic or nitric acid should I ever need to etch my own boards. What could possibly go wrong? :v:

I've always thought about etching boards, but in the end I never need anything so fast that oshpark can't satisfy me. The only downside is cost goes up pretty quick once you start talking big boards. You can't really get a low volume of anything bigger than 20cmx20cm for a reasonable price.

Cnc milling boards is way better than mucking around with etching solutions.

[QUOTE=DrDevil;49285514]Cnc milling boards is way better than mucking around with etching solutions.[/QUOTE] CNC mill costs more dole though, and also takes up more space. It's a good investment if you're in the serious end of the hobby scale or low volume rapid prototyping in smaller companies.

[QUOTE=Van-man;49285535]CNC mill costs more dole though, and also takes up more space. It's a good investment if you're in the serious end of the hobby scale or low volume rapid prototyping in smaller companies.[/QUOTE] Or check out your nearest hackerspace if they happen to have a cnc mill. That's how I get to mill my boards for the price of FR-4 copper clad.

[QUOTE=DrDevil;49285615]Or check out your nearest hackerspace if they happen to have a cnc mill. That's how I get to mill my boards for the price of FR-4 copper clad.[/QUOTE] Would require that the closest one isn't almost 70 Km away :v:

K, first attempt at home, learnt things. [t]https://i.imgur.com/CcbidG7.jpg[/t] 1) Toner transfer was not good enough. But I already got a suggestion from someone, I reckon that'll fix that. 2) No copper pour. I need it, regardless of me wanting it or not. 3) Didn't cut the board well enough. Need to transfer tone and then really trim it all the way to the edges. 4) I underetched it on purpose because I had no idea if the copper was fine under the toner. But now I know I can trust the toner.

I've found using vinyl sheet (the kind that is sticky on one side) is the best medium for toner transfer, I get perfect transfers every time even with an unmodified laminator, also get a cheap laminator. Clean the board very well before transfer, I use a bathroom surface cleaner and a sponge, you could also use a very fine wire wool but it's best avoided, solvents are not needed as long as you keep your fingers off it. Keep in mind if you do a copper pour to leave a decent bit of space between the pour and your circuit, without solder mask it's easy to create a short when you go to solder. Don't worry about over etching, it usually isn't a problem unless you leave it for a very long time.

[QUOTE=DrDevil;49285615]Or check out your nearest hackerspace if they happen to have a cnc mill. That's how I get to mill my boards for the price of FR-4 copper clad.[/QUOTE] For the trace widths that I typically use (Typically 12 mills/0.33mm), I could never get clean/close cuts with the PCB-CNC avail at my Uni. It just seems more precise for etching/photolithography.

[QUOTE=LoneWolf_Recon;49288637]For the trace widths that I typically use (Typically 12 mills/0.33mm), I could never get clean/close cuts with the PCB-CNC avail at my Uni. It just seems more precise for etching/photolithography.[/QUOTE] Selection of the correct milling bit is crucial for this. With mine I could easily get a milling-diameter of 0.2mm, you your trace width would easily be within possibility on the cnc I have access to, and it's a lower end mill.

Oh, so you want to use the chip in that [URL="http://www.ebay.com/itm/AD9850-Module-DDS-Signal-Generator-0-40MHz-2-Sine-Square-Wave-Circuit-Diagram-/171435129283?hash=item27ea5479c3:g:U0QAAOSwd4tT~DWU"]$10 ebay signal generator[/URL] in your design? Well great, [URL="http://www.mouser.com/Search/ProductDetail.aspx?R=AD9850BRSZvirtualkey58430000virtualkey584-AD9850BRSZ"]that'll be $25[/URL]. If only you could get the counterfeit chips over here as easily as you can over there.

[QUOTE=papkee;49290939]Oh, so you want to use the chip in that [URL="http://www.ebay.com/itm/AD9850-Module-DDS-Signal-Generator-0-40MHz-2-Sine-Square-Wave-Circuit-Diagram-/171435129283?hash=item27ea5479c3:g:U0QAAOSwd4tT~DWU"]$10 ebay signal generator[/URL] in your design? Well great, [URL="http://www.mouser.com/Search/ProductDetail.aspx?R=AD9850BRSZvirtualkey58430000virtualkey584-AD9850BRSZ"]that'll be $25[/URL]. If only you could get the counterfeit chips over here as easily as you can over there.[/QUOTE] Hell, even with shipping you'd almost be better off just buying the break-out board and de-soldering it.

[QUOTE=Zero-Point;49291244]Hell, even with shipping you'd almost be better off just buying the break-out board and de-soldering it.[/QUOTE] Yeah but I'm a much better solderer than I am a desolderer, plus I'd rather know I've got the real deal especially if I might be selling the design in the future.

This is probably a really stupid question, but I want to learn. Will current increase as parallels circuits are added? If I have a series of 3 LEDs with one resistor that total 0.7 amps and have 5 identical series in parallel will that mean the circuit draws 3.5 amps?

Parallels things always stay the same voltage but amps are what change. So you would add up all the amps from each parallel section. Take a look at [url]https://learn.sparkfun.com/tutorials/series-and-parallel-circuits[/url] , it should give you quite a bit of info on both types

[QUOTE=papkee;49291325]Yeah but I'm a much better solderer than I am a desolderer, plus I'd rather know I've got the real deal especially if I might be selling the design in the future.[/QUOTE] Why don't you just add a socket for the breakout board?

3D models are awesome. [url]http://imgur.com/a/7ttx8[/url]

You can embed imgur albums now. [media]https://imgur.com/a/7ttx8[/media]

[IMG]http://i11.photobucket.com/albums/a166/ballsandy/IMG_2080.jpg[/IMG] There's a Japanese person out there somewhere. 50 years ago they thought that using foam was a great alternative for springs in this motor brush assembly. If I ever find who this person is, dead or alive, I will fuck their shit right up for doing something so amazingly stupid.

[QUOTE=papkee;49291325]Yeah but I'm a much better solderer than I am a desolderer, plus I'd rather know I've got the real deal especially if I might be selling the design in the future.[/QUOTE] Just worry about proto-typing for now, if you get into any actual marketing phase then whatever loans you have to take out should be able to take care of it, just keep the cost of the Real McCoy in the back of your mind when you pitch it to investors. [editline]11th December 2015[/editline] [QUOTE=pentium;49295507][IMG]http://i11.photobucket.com/albums/a166/ballsandy/IMG_2080.jpg[/IMG] There's a Japanese person out there somewhere. 50 years ago they thought that using foam was a great alternative for springs in this motor brush assembly. If I ever find who this person is, dead or alive, I will fuck their shit right up for doing something so amazingly stupid.[/QUOTE] Japan used to be what China is today: Cheap cheap cheap. Wouldn't surprise me if you found shady American companies doing the same thing.

I love that [url=https://www.sparkfun.com/products/13745]hobbiest grade SATCOM[/url] is now a viable option. Admittedly it isn't hard to put the basic transceiver module on anything, but this breakout board is cheaper than the module from any other supplier I can get the price from.

Here I was saving a 12' satellite dish for this eventual day. Damn how things can become compact.

[QUOTE=pentium;49299022]Here I was saving a 12' satellite dish for this eventual day. Damn how things can become compact.[/QUOTE] Out in the boonies of BC you should be able to pick up one of those massive 6/9ft satellite dishes for pennies. Go make yourself a 1.421GHz (Hydrogen Line) radio telescope out of an RTLSDR.

So i got my hands on what i think is a controller for anemometer used for cranes via a friend at work. I've been trying to figure out what the connector type is that's used on this thing, but haven't found an answer yet. Not even on their [URL="http://www.smie.com/uk/pages/index_anemometre.html?=anemometre.html"]website[/URL]. [t]https://dl.dropboxusercontent.com/u/64443729/smie/WP_20151212_11_29_03_Pro.jpg[/t] [t]https://dl.dropboxusercontent.com/u/64443729/smie/WP_20151212_11_31_28_Pro.jpg[/t] [t]https://dl.dropboxusercontent.com/u/64443729/smie/WP_20151212_11_31_43_Pro.jpg[/t] [t]https://dl.dropboxusercontent.com/u/64443729/smie/WP_20151212_11_31_51_Pro.jpg[/t] [t]https://dl.dropboxusercontent.com/u/64443729/smie/WP_20151212_11_31_59_Pro.jpg[/t] Anybody here know what this type of connector is called? Edit: Seems that it might be a Microphone multi-pin 3pin connector but there seem to be a lot of similar connector's.

I'm going to say it looks similar to a GX16-4 (4 pin) connector with a pin removed.

[QUOTE=Cakebatyr;49300174]I'm going to say it looks similar to a GX16-4 (4 pin) connector with a pin removed.[/QUOTE] That's what i'm thinking as well. Came across it via amazon. [URL="http://www.amazon.co.uk/Miki-Co-Aviation-Connector-Screw/dp/B010JGOAEQ/ref=sr_1_20?ie=UTF8&qid=1449917814&sr=8-20&keywords=3+Pin+Screw+plug+connector"]This [/URL]should be what i need.

[QUOTE=Cakebatyr;49299441]Out in the boonies of BC you should be able to pick up one of those massive 6/9ft satellite dishes for pennies. Go make yourself a 1.421GHz (Hydrogen Line) radio telescope out of an RTLSDR.[/QUOTE] Too bad I have no inclination of doing anything like this, my great-grandmother's old house still has an old 6-foot dish with the linear actuators still on it. :v:

[QUOTE=Cakebatyr;49298984]I love that [URL="https://www.sparkfun.com/products/13745"]hobbiest grade SATCOM[/URL] is now a viable option. Admittedly it isn't hard to put the basic transceiver module on anything, but this breakout board is cheaper than the module from any other supplier I can get the price from.[/QUOTE] $12/month for neigh-unlimited access for Iridium satellite usage is pretty affordable, about the same maintenance cost for say owning a domain name. And then ~$0.15 for every 10 bytes is quiet decent.