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Ground Needed\Stray Voltage? by James Pillyhood - Wed, 13 Jul 2016 23:38:51 EST ID:LMSWX1C6 No.6975 Ignore Report Reply Quick Reply
File: 1468467531486.png -(73990B / 72.26KB, 300x180) Thumbnail displayed, click image for full size. 73990
So I got a new attic fan and lighting wired up and there is no ground available on the circuit coming from the breaker. Option one I'm seeing is to run a wire out the wall, tucked under the siding all the way to the ground rod, bloating this "simple" project even more; or just say fuck it and not run a true ground to it, even though I spent the time tying all the ground wires together; third option bite the bullet and buy a GFCI breaker.

Problem 2, when I put the voltmeter to the case of the fan, after flipping the breaker on, I get 1 volt on the case. Should I be concerned with this, is this excessive stray current?
Cedric Cunkinferk - Thu, 14 Jul 2016 21:15:26 EST ID:3ODb0gls No.6976 Ignore Report Quick Reply
I would probably just install a fuse on the power wire to the fan.
Lillian Brookbanks - Thu, 14 Jul 2016 23:37:17 EST ID:LMSWX1C6 No.6977 Ignore Report Quick Reply
Suppose that could work. Haven't seen a fuse outside of a car circuit in a long time. Don't think any stores even carry holders around here. Have to order one.

Instrument cable instead of speaker cable? by Alice Clayridge - Wed, 29 Jun 2016 19:07:44 EST ID:wpTfjl5n No.6972 Ignore Report Reply Quick Reply
File: 1467241664728.jpg -(626424B / 611.74KB, 1025x659) Thumbnail displayed, click image for full size. 626424
I let friends use my fucking sound system and I found out they ran instrument cable instead of speaker cable from the powered mixer to the speakers for their dance music show and now a.) there was popping for like 3 seconds mid sound-check the next day but hasn't happened since and b.) the power amp limiter LEDs come on for two seconds right when you start it up but has yet to come on any time after that. Should I be worried? This system is brand new and I'm really upset about this.

Pictured is the power amp used. The manual doesn't say anything about what the limiter lights are supposed to do at startup so I don't know if that's normal.
Simon Hummlenot - Wed, 29 Jun 2016 23:44:42 EST ID:LMSWX1C6 No.6973 Ignore Report Quick Reply
/m/ Might be the proper board.

How many amps does it dump out the powered end, and how long was the line? If itt was a small 18ga instrument patch, under several amps, and wasn't remotely pushed to peak, it was probably not an issue.
Was the pop like when you plug in a line? That might be a loose jack issue.

Thing two. Don't lend gear unless it's a beater, or you know the individual will buy you a new one it they damage it(this works with coworkers, because you know they have actual income).

Electrical Sharegineering by Polly Dartville - Sat, 27 Feb 2016 03:24:15 EST ID:EGgJzstS No.6919 Ignore Report Reply Quick Reply
File: 1456561455718.gif -(1149890B / 1.10MB, 500x500) Thumbnail displayed, click image for full size. 1149890

I'm a millionaire drunk stoner with a pretty complete knowledge of everything concerning electrical engineering. Ask me anything!
17 posts and 6 images omitted. Click Reply to view.
Charles Chorringkag - Mon, 23 May 2016 13:06:20 EST ID:Mammg+Yw No.6960 Ignore Report Quick Reply
1464023180507.png -(69902B / 68.26KB, 1638x864) Thumbnail displayed, click image for full size.
If I used a simple filter it would only work for the note that the filter removes. I would have to make the filter frequency controllable by the input frequency, so it would be just as complicated as what I'm trying to do now.

The circuit I have so far actually simulates rather well. With input signals above 1kHz, I can get the oscillator level to match the input rather well from 10mV to 1V, with a response time around 1ms. The problem is that lower frequency signals cause the control voltage to oscillate, which really garbles the PLL signal and thus the output. The filter following the recitifers is well overdamped, so I'm thinking the problem has something to do with the non-linear response of the JFET VCA. I wanted to keep using JFETs for cost reasons, but I may switch to something optoelectronic, since the response is typically much smoother/slower.
Ian Sublingshit - Wed, 25 May 2016 02:50:49 EST ID:T91euWtk No.6961 Ignore Report Quick Reply
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Ugh, dude. Here's a protip for this kind of thing; nobody wants to see your specific implementation unless they getting paid. Again I'll try to keep it simple.

So your high band frequencies work well with your shit. Great. USE FILTERS LIKE I SAID! Split your input signal into two, with one going through a lowpass filter to remove those sub kilohertz signals. Feed that signal into your existing setup and you're golden for that part of the frequency spectrum.

Take your other output and filter the high band with a highpass filter, then use a bandpass filter to eliminate whatever frequency range between 0-1kHz you desire. Tie those outputs together and wow you have the whole spectrum without having to deal with your nonlinearity.

Now this might sound confusing if you don't understand that filters can suppress a range of frequencies, not just a specific one. Go read up on how passive and active filters are constructed.
Ebenezer Pummletork - Wed, 25 May 2016 13:04:02 EST ID:Mammg+Yw No.6962 Ignore Report Quick Reply
I don't think you understand what I'm trying to do. I want to remove only the fundamental frequency of a note from a guitar or other instrument and leave the harmonics untouched. It should be able to do this over the entire range of the instrument. If I use any fixed-frequency filters in the signal path, it will only work correctly for a certain range. For example, if I eliminate 500-1000 Hz with a filter, the effect will work for this range of input frequencies; but if I play a note at 250 Hz, it will filter out the first and second harmonic (500 and 1k Hz) and leave the fundamental untouched; if I feed in a note at 2000Hz it won't do fucking anything. If I make the bandwidth any larger than an octave, it won't work for ANY input frequency because the for it will start filtering out the harmonics of any note within the filter range. There is no way to get more than one octave of useful range with static filters because I specifically want to remove "one" frequency which can vary over several octaves. Something MUST track the input frequency; it cannot be done with fixed-frequency filters.

Don't be so condescending. I understand how filters work. You mixed up highpass / lowpass as well as bandpass / bandstop.
Emma Hommlefield - Fri, 03 Jun 2016 03:32:25 EST ID:T91euWtk No.6969 Ignore Report Quick Reply

Yeah well fuck you. I can't see any way of doing this easily with analog components, because you CAN isolate a fundamental signal via analog methods but it becomes impractical with a large number of frequencies. Just use a cheap microcontroller to examine the current fundamental and apply the correct filtering. It's not expensive, like 10bux for a top of the line processor.
Shit Bizzleforth - Tue, 07 Jun 2016 21:48:46 EST ID:7ztzoB70 No.6970 Ignore Report Quick Reply
Calculus, asides from obvious shit like wolfram alpha and its rubbishy pay to get step by step shit can you recommend any good resources or books to learn from?

DIY underwater home by Ernest Clinkintid - Thu, 04 Feb 2016 17:45:26 EST ID:S8hxXMl5 No.6894 Ignore Report Reply Quick Reply
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possible? i know it is possible but i'm talking about the average person
6 posts omitted. Click Reply to view.
Basil Burrymurk - Mon, 15 Feb 2016 10:41:16 EST ID:a607tU9R No.6910 Ignore Report Quick Reply
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Caroline Bruckleville - Mon, 15 Feb 2016 12:03:27 EST ID:nivRxxRT No.6911 Ignore Report Quick Reply
i live in a town called bellevue..
Martha Fimmleman - Tue, 19 Apr 2016 21:41:14 EST ID:JT+zLDlO No.6947 Ignore Report Quick Reply

LMFAO this brings back memories. Thank you so much anon.
Shitting Gottingstodge - Thu, 21 Apr 2016 19:08:38 EST ID:uywTW9Q3 No.6949 Ignore Report Quick Reply
How the heck would you build that? I feel like having an air-lock and a system to keep the interior at 1 bar pressure alone would cost more than $100,000.

I feel like the most feasible, cost-effective option here would be to build a giant ventilation duct that sticks well out of the water (high enough so that it's never underwater, even in the case of extreme flooding) and to pump air in and out of the underwater area.
Samuel Bembleridge - Tue, 31 May 2016 12:37:46 EST ID:cNouZAzb No.6967 Ignore Report Quick Reply
What if instead of using a water lock you just counteract pressure mechanically?

MODEL SHIT IN A GAME BRUV by Hugh Bunshit - Tue, 03 May 2016 23:45:58 EST ID:/SWUqKch No.6955 Ignore Report Reply Quick Reply
File: 1462333558556.jpg -(26457B / 25.84KB, 657x403) Thumbnail displayed, click image for full size. 26457
I want >>>/vg/664016 to succeed so I'm shamelessly shilling it. I personally am (extremely slowly) working on a city simulator, using historical public census/weather data from various cities as input. It's a big project and I've only just begun but it feels right.

But anyhow, visualizations feel good as hell and gamedev is a hobby that works with modeling interests. I bet a whole bunch of you have played Banished or Cities: Skyline or DF or whatever else, and been like "huh" or "nah bro, what they should have done there..."

So maybe you should get into amateur gamedev. The barrier to entry is low. The tools are free. It's a good hobby.
Archie Dracklestot - Wed, 04 May 2016 01:24:31 EST ID:CUcr8ZcI No.6956 Ignore Report Quick Reply
Yep it is a good hobby, and also a ton of work. Good luck!

Electrochemistry Support by Thomas Murdcocke - Tue, 26 Apr 2016 23:40:21 EST ID:9ofAWPV8 No.6952 Ignore Report Reply Quick Reply
File: 1461728421005.jpg -(441377B / 431.03KB, 1920x1157) Thumbnail displayed, click image for full size. 441377
Well, i've got my chemical engineering degree recently and i'm in my first freelance job. Need to design a desalination process; as a pretreatment, i require an electrolysis cell to electrolyse seawater producing Cl2, H2 and NaOH, the later is the main agent of the pretreatment.
As such, i need to understand and design an electrolytic cell for the purpose, but my electrochemistry in uni was shitty to non existing, and besides RedOx understanding, i'm naked at it. Can you lend me material to read an learn? I'm facing death with "Electrochemical methods and fundamentals (Bard & Faulkner)"cause it has like 800 pages and is pretty thick.
Also, i've found some ppt's lessons, but they lack the teacher. Anything works, but i'm focusing in sizeing and evaluation by now.
Alice Follydag - Sat, 30 Apr 2016 08:55:55 EST ID:Nf9XqI8L No.6953 Ignore Report Quick Reply
You shouldn't have a job, let alone a degree, if you don't understand RedOx, nor even have the energy to read a 800 page book to help you.
Isabella Sushstone - Sun, 01 May 2016 19:03:03 EST ID:9ofAWPV8 No.6954 Ignore Report Quick Reply
what a nice reading comprehension...

S-senpai.. my piston rods are moving on their own by Alice Dackleshit - Sat, 13 Feb 2016 23:26:48 EST ID:eLQ43SxB No.6909 Ignore Report Reply Quick Reply
File: 1455424008489.jpg -(63461B / 61.97KB, 1280x720) Thumbnail displayed, click image for full size. 63461

You know, the Engie board was originally my idea, but it's taken me this long to find suitable porn.
Graham Grimway - Wed, 20 Apr 2016 20:29:46 EST ID:UWdc7qZ1 No.6948 Ignore Report Quick Reply
well that was fucking weird

so if you want decent engineering videos I like AvE and clickspring for sure.

fuck by Faggy Blettingfuck - Tue, 22 Mar 2016 16:28:28 EST ID:ej7dKnE7 No.6935 Ignore Report Reply Quick Reply
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So after being out of high school for 7 years now, I want to go back to school for aerospace engineering. No engineering schools worth a single fuck anywhere within driving distance. LOL, fuck me, right??
Claus Cunt - Thu, 24 Mar 2016 16:09:38 EST ID:842pDf5G No.6939 Ignore Report Quick Reply
Yo Taylor? Move to New England fag.

RGB Strip Wiring by Polly Dashwure - Wed, 09 Mar 2016 19:47:22 EST ID:0sTD210V No.6926 Ignore Report Reply Quick Reply
File: 1457570842902.png -(11461B / 11.19KB, 954x282) Thumbnail displayed, click image for full size. 11461
Does anyone know how these RGB strips are supposed to be wired/controlled?
I was able to wire a PC fan connection (with power and ground) to the +12v on the LED strip, and the ground to either an R, G, B, or combination.
So what I don't understand is why the ground connection is what determines the color, and also how am I going to vary the colors to get all possible combinations other than the current 8 combinations I can make.

If I use the fan controller's pot to control the GROUND wire, will that even work? If so, will I be able to wire each individual R G B to a separate knob on the fan controller?
Polly Dashwure - Wed, 09 Mar 2016 20:28:41 EST ID:0sTD210V No.6927 Ignore Report Quick Reply
This is confusing. The fan controller has it's own molex power & ground. It's not as easy as just wiring the fan's positive outputs from the controller to each R G B, because I'd end up with 4 12v inputs going the LEDs.
But it's confusing because I have
+12V; R; G; B. So that means at least one of those R G B's has to be a ground connection. Are they ALL a ground connection? Will a potentiometer even work when wired on a ground wire?

Curved actuator by Opforian - Thu, 28 Jan 2016 18:36:41 EST ID:djMkKCnU No.6886 Ignore Report Reply Quick Reply
File: 1454024201573.png -(21566B / 21.06KB, 1152x648) Thumbnail displayed, click image for full size. 21566
Has anyone ever produced a hydraulic actuator like this?
3 posts and 1 images omitted. Click Reply to view.
Whitey Crubbleforth - Sat, 20 Feb 2016 04:09:12 EST ID:XN1E8GAE No.6914 Ignore Report Quick Reply
looks like a dildo mold
Fucking Hublingson - Sat, 20 Feb 2016 23:41:00 EST ID:fLI4doDn No.6915 Ignore Report Quick Reply
Not completely related, but take a look at the kriss vector handgun/smg/whatever
It also uses a curvature for the slide similar to your design there.
Henry Bunbury - Sun, 28 Feb 2016 20:18:39 EST ID:+u3PHuSh No.6921 Ignore Report Quick Reply

OP 1 flycut one side down, mill locating tabs down, M0 then flip, mill out and profile with corner round first side, leave locating/mounting tabs on both ends all 5 sides of them having been machined at this point
OP 2 use a plate fixture that holds all the profiled tangents, mounts and located off of the fully machined ends. finish profiling
OP 3 supported in soft jaw, put one end to stop, and have the other end towards spindle where gets corner rounded
OP 4 same as last op, you can do both ends in the same soft jaw, at the same time, on the opposing ends, assuming the operator is instructed to hold +/-.001 for tooling between OP1&2. On the first part and last part of the batch there's no support on the far end of the jaw, so it will sit cockeyed and need a support block used.
Henry Bunbury - Sun, 28 Feb 2016 22:07:50 EST ID:+u3PHuSh No.6922 Ignore Report Quick Reply

It should also be noted that if you're doing the spindle time in house and want to save money on not buying corner rounds, you could just hemstich the curvature with a ball nose. At the expense of added spindle hours to the part, especially if you don't have look ahead features or a high RPM spindle. Plus if the resolution and accuracy of the machine isn't there it might look like shit and need a lot of polishing.
Other wise you can always make corner rounds out of tool steel yourself. There's a number of tutorials on making profiling tools. Especially for cutting prototyping costs.
Alice Gublingdock - Mon, 29 Feb 2016 17:50:31 EST ID:fEVjpFqe No.6923 Ignore Report Quick Reply
I'm glad the dildo drive is finnally being invented..

Georgia Guide Stones? by Oliver Chungerbury - Wed, 20 Jan 2016 18:26:23 EST ID:cjMtRwMf No.6872 Ignore Report Reply Quick Reply
File: 1453332383556.gif -(127671B / 124.68KB, 574x383) Thumbnail displayed, click image for full size. 127671
Does anyone have any info on how these were built?

Or what they are specifically made out of to survive the coming apocalypse?

I have these sources, but does anyone have any more fringe sources on these monuments?

>or possibly proof of who or what put them there for what reason?


Possible proof of satanic sacrifices going down on the top of the stones
George Fundersetch - Wed, 20 Jan 2016 18:29:54 EST ID:8r0/mD74 No.6873 Ignore Report Quick Reply
>how these were built?

>Or what they are specifically made out of

Dude it's right there in the wiki link YOU posted
Phoebe Sollyfield - Thu, 21 Jan 2016 07:52:29 EST ID:Wog5XsYj No.6874 Ignore Report Quick Reply
>Or what they are specifically made out of to survive the coming apocalypse?

Phoebe Sollyfield - Thu, 21 Jan 2016 07:53:08 EST ID:Wog5XsYj No.6875 Ignore Report Quick Reply
or try
Albert Gubberchen - Fri, 26 Feb 2016 18:53:42 EST ID:I4/79hKb No.6918 Ignore Report Quick Reply
but what if they were made with SPACE granite!

Found this and want to repair, any advice? by Polly Blashtick - Fri, 26 Feb 2016 18:40:10 EST ID:G0anMYhU No.6916 Ignore Report Reply Quick Reply
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My friend and I found this electric piano thrown out on the curb by a church so we too it. It works but one of the speakers makes a loud buzzing noise. I want to try and repair it myself , last resort we take it to a repair shop. I'd like to try and learn how to do this though. Any pointers?
Charles Gungerfuck - Fri, 26 Feb 2016 18:46:28 EST ID:jIX0poLH No.6917 Ignore Report Quick Reply
Open 'er up and check the wires leading to the buzzing speaker for rust/corrosion. Look carefully at the solder connecting the wires too, check for any cracks. You may have to de-solder the old wires off and affix a new one. It's pretty easy to do!
Alice Gublingdock - Mon, 29 Feb 2016 17:52:24 EST ID:fEVjpFqe No.6924 Ignore Report Quick Reply
The sound quality will never work, give up, buy a new one stimulate the Anerican economy, if not you're clearly a commie #betterdeadthanred
Shit Nasslehadge - Fri, 11 Mar 2016 17:40:15 EST ID:DwGOpxIe No.6929 Ignore Report Quick Reply
*Chinese economy

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