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Forced semester off, can study ahead online? by Edwin Ferryshit - Thu, 13 Mar 2014 22:27:21 EST ID:9+I+k5VX No.6216 Ignore Report Reply Quick Reply
File: 1394764041986.gif -(902889B / 881.73KB, 312x176) Thumbnail displayed, click image for full size. 902889
Hey /Tesla/,

I was taking Calculus and CS courses last semester, but was suspended from registration due financial issues. These were both prerequisite classes for my intended major.

My question is are there any websites or libraries besides Khan academy that I could use to study Physics, Statics, and or Heat dynamics?
(Preferably with proper notation and formula.)
>>
Isabella Gemmerson - Thu, 13 Mar 2014 23:31:52 EST ID:CKZoWqYh No.6217 Ignore Report Quick Reply
MIT has a lot of open course material
http://ocw.mit.edu/index.htm
>>
Augustus Sombleford - Fri, 14 Mar 2014 18:40:42 EST ID:gJ2Omk9E No.6219 Ignore Report Quick Reply
Personally I'd study the textbook in advacnce. Find out what textbook the instructor uses.


Logging Circuit by Walter Daffingwell - Thu, 13 Mar 2014 03:13:51 EST ID:4fpX8pqx No.6210 Ignore Report Reply Quick Reply
File: 1394694831517.png -(3606B / 3.52KB, 118x44) Thumbnail displayed, click image for full size. 3606
I wouldn't know where to begin here, but I need to log the opening of a small door.
So I could have some kind of circuit, and there would be little metal contacts on the door and the hinge, then whenever the door is opened -> circuit broken -> log that somehow.

Does anyone know I could make this logging device?
>>
Nigger Cheffingville - Thu, 13 Mar 2014 21:01:18 EST ID:2POYse6P No.6215 Ignore Report Quick Reply
arrange it so when the door is opened, a lever moves and presses down on a key on a manual typewriter.
>>
OP - Fri, 14 Mar 2014 11:08:49 EST ID:4fpX8pqx No.6218 Ignore Report Quick Reply
>>6215
While that would get the number of opens, what I'm looking for is the time/dates of them.

I've done this by setting up a webcam that activates when it detects motion.
/thread


fucking smps - how do they work? by Anonymous - Sat, 22 Feb 2014 19:18:54 EST ID:kU/b2Op8 No.6154 Ignore Report Reply Quick Reply
File: 1393114734756.jpg -(37260B / 36.39KB, 385x384) Thumbnail displayed, click image for full size. 37260
hi tesla,
i'm building a led panel with integrated fan and don't know how to run a pc fan from the same voltage source. the fan is rated 12V @ 450mA, the supply does up to 1A and has 5V left after the leds. the fan needs probably 2A at startup and it should also run when the leds are off.

a switch mode dc/dc converter seems a good idea. it should boost the 5V to somewhere between 6 and 10 V and also deal with the excess voltage when leds are turned off, ie. short circuited via dpdt switch. a look at wikipedia tells me buck-boost or sepic converters can do that.
downsides, what to watch out for? don't most those converters hardly work in parallel?
are there alternatives? a zener would be enough to limit the volts but only with an ohmic load.

i want to learn the basics and take a closer look, just asking if i am headed in the right direction basically.
7 posts and 2 images omitted. Click Reply to view.
>>
Cedric Diblingbanks - Sun, 09 Mar 2014 00:21:19 EST ID:kU/b2Op8 No.6202 Ignore Report Quick Reply
1394342479532.png -(60043B / 58.64KB, 1024x723) Thumbnail displayed, click image for full size.
>>6165
Working in a simulator I could prove my idea in principle. This is just a modified example circuit that comes with LTSpice having 5V 440mA on the output. Integrating the input over a low-pass and subtracting the low-pass resistor voltage drop-off 36V 80mA appear to be stepped down with 83% efficiency. great success. The voltage breaks down over 1A, though.

... was quite happy to see at least some results. Now i am eager to advance this to incorporate a microcontroler to schedule the light, log and regulate temperature, i even found cheap humidity sensors.


braindump:

The resistor is supposed to limit the input current to be collected by the cap and given to the switcher in very short high current bursts.
At startup it still takes almost 1A leaving none for the LEDs.
Trial and Error brought me to this setup using another low-pass at the gate of a mosfet, that switches on when the cap is sufficiently loaded. I tried to increase the slow start effect using an Inductance. The usefulness is questionable. A mA ringing with the cap happens for microseconds at startup - through the MOSFET. When tested separate from the switcher it's gone! Simulation without the inductance fails because the calculation exceeds memory, WTF? Same if only one of the Motors represented by each RCL network to the right is used.

My approach is a million monkeys on a typewriter. I tried a few example test circuits before one was found that worked with different input voltages. The output voltage is below my requirements and i am dumbstruck. I think the voltage divider over the feedback pin needs to be adjusted. Instinct tells me that's not all there is to it. That's why I am hesitant to test with real components. Is the simulation close enough to reality?
What components anyway, capacitors have a series resistance? at least LT Spice has a datafield for it, but that was left empty.

The lt10xx series is supposed to be as simple to use as an lm317. lm317 is not exactly a piece of cake either. there is tons of material on this subject but i don't have the foundation, e.g. impedance or power factor calculation to work on it.
>>
Sidney Sollernack - Sun, 09 Mar 2014 03:37:13 EST ID:vXg79lPA No.6203 Ignore Report Quick Reply
>>6202
>Integrating the input over a low-pass and subtracting the low-pass resistor voltage drop-off 36V 80mA appear to be stepped down with 83% efficiency. great success. The voltage breaks down over 1A, though.

Where is this 36V coming from? I thought your power supply was only 12V. And what's the point of the RC in front of the switcher? The resistor is only going to burn current that's used by your fans. And of course the voltage breaks down at 1A. One Amp across a 36 ohm resistor is 36V. At that current, all of the voltage is dropped across the resistor. It's not like your power supply can output that much voltage and current anyway.

>I tried to increase the slow start effect using an Inductance. The usefulness is questionable.

If you want it to start up slower, why wouldn't you just increase R8? There's no need for the inductor.

>The output voltage is below my requirements and i am dumbstruck.

The output voltage is 5V according to your graph. The LT1076 has an output of 5V. It's a 5V step-down regulator. What else did you expect?

It sounds like you're trying to build a space shuttle to pick up the groceries.
>>
Cedric Diblingbanks - Sun, 09 Mar 2014 15:52:51 EST ID:kU/b2Op8 No.6204 Ignore Report Quick Reply
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>>6203
>Where is this 36V coming from? I thought your power supply was only 12V. And what's the point of the RC in front of the switcher? The resistor is only going to burn current that's used by your fans
The PSU is 36V, Vout is the regulated 5V.
The powerloss of R5 is only 0.2W, no biggie. The current spikes on the switcher input would be way too high for the psu, judging by the specs. Although the supply might withstand that, i am not gonna risk it. the capacity of the filter was chosen randomly. if you criticized that, i would understand. tips for choice of the the cap would be welcome, there are so many types and i need them rated for the voltage and ripple current,

12V on the fan would be nice to have, but it should run with less and quieter at that.

>If you want it to start up slower, why wouldn't you just increase R8? There's no need for the inductor.
Don't want the rise time of U_DS too high. Don't know if it really matters.
>It's a 5V step-down regulator
No, this is a lt1076. You might think of lt1076-5. That one i didn't know, it's interesting.

I am still concerned if the switch topology is suitable. There's so much more to learn and this project gives me a reason to explore.
>>
Jarvis Faddlekane - Thu, 13 Mar 2014 02:50:50 EST ID:NimfZmq9 No.6209 Ignore Report Quick Reply
>>6204
admittedly, it's written a bit confusing. first i didn't understand myself when i just reread.
The resistor in front of the switcher IC has to be at least 36 Ohm so that the current is limited to 1A, because else the voltage might be cut off by the overpower protection of the PSU.
nb because you show not much interest
>>
Archie Simmerkadge - Sun, 23 Mar 2014 15:54:37 EST ID:kahK/jZ9 No.6225 Ignore Report Quick Reply
The fan needs volts to start not amps
Some 12volt fans do start on 5volt you might consider getting one.


Engineering youtube channels by Charles Cheddlestone - Thu, 06 Mar 2014 16:33:04 EST ID:CKZoWqYh No.6195 Ignore Report Reply Quick Reply
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Post some good ones.
I only have found this one:
EEVblog, some Aussie who does electronics videos.
http://www.youtube.com/user/EEVblog


Amplifier Circuitry by Barnaby Nongershaw - Mon, 03 Mar 2014 10:40:09 EST ID:MM8P09Mv No.6173 Ignore Report Reply Quick Reply
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Soup /tesla/

The other day, I plugged in my 100W solid state Marshall Reverb, and the only noise to come out of the speakers was the loudest, most irritating buzzing noise.

So I exposed the circuit board and turned it on. Some sparks shot out from somewhere very close to those two blue "things". Dammit, Jim. I'm a musician, not an engineer.

Now, assuming the actual circuit board isn't fucked, how would I go about replacing those? What are they even called?

I already tried to get the reverb pan fixed by Marshall, but it's so old that they don't want to fuck with it.
8 posts and 1 images omitted. Click Reply to view.
>>
Doris Pummernedge - Tue, 04 Mar 2014 08:25:56 EST ID:PJ4BpwOn No.6182 Ignore Report Quick Reply
>>6180
Told ya once told ya again. You need to short them out. grab an insulated screw driver, touch it to two leads at the same time. This will short them out.
>>
Simon Dimbleson - Tue, 04 Mar 2014 11:44:31 EST ID:MM8P09Mv No.6183 Ignore Report Quick Reply
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Forgot I took this picture as well.
>>
Nicholas Shittingfield - Tue, 04 Mar 2014 18:19:59 EST ID:kWAgYbio No.6185 Ignore Report Quick Reply
Do a shit ton of research and find youtube videos/stories is my advice. Amp repair guys are all "guru's" and they'll charge you guru price for any kind of repair.
>>
Eugene Baffingmit - Tue, 04 Mar 2014 19:45:15 EST ID:2POYse6P No.6186 Ignore Report Quick Reply
>Looks like you blew the capacitor on the left
based on what evidence?

>As in, you could die doing it if you fuck up.
this is incredibly unlikely from a 50V cap. stop scaremongering.
>>
Oliver Blatherdock - Wed, 05 Mar 2014 09:49:57 EST ID:MM8P09Mv No.6189 Ignore Report Quick Reply
>>6185

>Amp repair guys are all "guru's" and they'll charge you guru price

Naw, the guy I know probably won't charge me anything. I just don't want to have to wait.


spycam reverse engineering by Walter Hummlepit - Sun, 02 Mar 2014 07:28:45 EST ID:cqsZD3rA No.6170 Ignore Report Reply Quick Reply
File: 1393763325374.jpg -(73384B / 71.66KB, 387x381) Thumbnail displayed, click image for full size. 73384
Hello /tesla/, any idea what this chip do?
I've got a STK3350 spycam, but i have other ideas to it. i want to modifiy it to drive an RC car over wifi, and i want to reverse engineer it. i can telnet into it can enable ftp, it has busybox, has a MIPS cpu and the wifi "shield" has tons of GPIO, even the system itself has a GPIO executable binary but i don’t know how to work it. Any idea where to start?
>>
Walter Hummlepit - Sun, 02 Mar 2014 07:48:22 EST ID:cqsZD3rA No.6171 Ignore Report Quick Reply
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this is the wifi module on top of the video module. The page it loads tell me that this is is a RT5350 module, but the system loads an RT2860... the under the masked part there is only MAC some 2d code, and a serial number.
>>
Cyril Narrypirk - Sun, 02 Mar 2014 10:58:45 EST ID:kU/b2Op8 No.6172 Ignore Report Quick Reply
>>6170
is that the mips soc?
you probabbly searched for the part number and didn't find a datasheet because the manufacturer hasn't published it to the public or it is written in moonrunes.
the function of the chip is easier to guess when knowing where on the board it is and where it connects to.
maybe the RT2860 ... driver(?) works for both versions.
you assume the GPIO executable binary is a cmd to modify the ports? your expression is not quite clear.

reverse engineering is no picnick. if you are lucky there is a compiler tool chain, for mips there is, i guess, if not you write one, at least asm/disasm (and linker?). disassemble the gpio cmd, extract the bootloader, map memory regions, write you own procedures as PoC come to mind.

i really have no idea though, it seems easier to build your own or use ready made RC stuff. i was looking for camera modules before, shit is expensive.


The smallest mechanisms you ever did see by David Clembledare - Thu, 16 Jan 2014 18:50:27 EST ID:5gD9lQi4 No.6099 Ignore Report Reply Quick Reply
File: 1389916227194.jpg -(99414B / 97.08KB, 750x563) Thumbnail displayed, click image for full size. 99414
Here's what I need: A way of building a bunch of super small mechanisms with limited resources I can buy at the local hardware store and no real machining tools other than a dremel.
I enjoyed making an alcohol stove with no power tools using Tetkoba's videos on Youtube. I want to do more stuff like that.
If anyone has ideas about what to build and how to build it (mainly plans for the mechanisms), that would be super duper!
>>
David Passlewune - Fri, 24 Jan 2014 13:29:50 EST ID:uEfymhfr No.6105 Ignore Report Quick Reply
>>6099
Watch the youtube videos from KipKay!
Tutorials and whatnot.
>>
Cyril Chummerchadging - Thu, 30 Jan 2014 02:13:50 EST ID:TRG9wKw/ No.6108 Ignore Report Quick Reply
build a furnace out of a can, plaster of paris, sand, and a torch, then smelt cans and put them into molds
>>
Phineas Hashshaw - Wed, 26 Feb 2014 21:10:03 EST ID:Jk2UBRNv No.6163 Ignore Report Quick Reply
Or build a fucking SOLARFORGE with a fresnel lens...


we academia now by Fanny Fuckingforth - Wed, 19 Feb 2014 01:51:22 EST ID:BKcz5mkY No.6147 Ignore Report Reply Quick Reply
File: 1392792682935.gif -(510061B / 498.11KB, 500x362) Thumbnail displayed, click image for full size. 510061
literally probably the slowest board on the site


still love you guys


we should start some open source projects, I'm down if you're down

I've been thinking of designing a mesh network guerilla internet that is independent of ISPs and their bullshit

how do we organize this?

i'm serious about this too
>>
Esther Bardwill - Wed, 19 Feb 2014 21:31:42 EST ID:2POYse6P No.6148 Ignore Report Quick Reply
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hyperlocal chat/data/sharing/social services, with message and data sharing via sneakernet (sd cards, ssds) or wireless to other neighborhoods. need weatherproof solar powered wifi boxes mounted on existing power and light poles.

develop a very thorough protocol standard, and then let people build their own hardware and software stacks that implement the standard.

you will never reimplement the existing physical internet infrastructure via ad hoc wireless. aim to provide an experience that is usable -- like the consumer internet as it was in, say, the year 2000.

OT: i once had an internet friend from surrey. are you them?
>>
Phoebe Blobbertut - Thu, 20 Feb 2014 05:39:23 EST ID:NH/ehRTH No.6150 Ignore Report Quick Reply
>>6148
>i once had an internet friend from surrey. are you them?
Holy shit I don't know but that's eerily close.

And everything you said is pretty much what i was thinking

maybe i know you

does your name start with a v?
>>
Anonymous - Fri, 21 Feb 2014 01:25:51 EST ID:kU/b2Op8 No.6153 Ignore Report Quick Reply
for a mesh network you need a lot of users or large coverage. HAM packet radio has large coverage, but only slow connection. some fancy shooting up satellites, also large coverage and slow, taking years for research of course.
for home router usage there is b.a.t.m.a.n., a protocol for wireless meshing in actual use.
p2p and freenode have (had?) the same aspiration as OP, don't think they took of.
i find academic projects for the solely educational purposes that are not actually usable hardly motivating and ideas already cheaply implemented a waste of time.

any other ideas?
>>
Phoebe Dendlelure - Sun, 23 Feb 2014 23:08:39 EST ID:/Alv3nG/ No.6160 Ignore Report Quick Reply
>>6147
I'm thinking of starting an open-source/hardware audio-mixer, DJ controller type device that could be used to control DJ or music production software.
>>
Hannah Fazzleridge - Mon, 24 Feb 2014 23:26:13 EST ID:bb3Upemj No.6161 Ignore Report Quick Reply
>>6160

please do so


Variable Expansion by Jack Fuzzleworth - Sat, 15 Feb 2014 19:42:29 EST ID:YZp2n0B6 No.6141 Ignore Report Reply Quick Reply
File: 1392511349325.jpg -(186753B / 182.38KB, 1571x2356) Thumbnail displayed, click image for full size. 186753
Hey guys and gals. I'm looking for something mechanical that expands and contracts lengthwise. Something like a baton or lightsaber. Only it has to be really tiny, like a pencil. But also have a fine resolution on how long/short it is. Does such a device exist??

Please let me know if you need some clarity.
>>
Jack Fuzzleworth - Sat, 15 Feb 2014 19:45:47 EST ID:YZp2n0B6 No.6142 Ignore Report Quick Reply
I'm also considering a tiny device as small as a pencil. But also, able to shift some weights outward/inward, so if you spun it around its center, its rotational intertia would be increasing/decreasing. Again, the caveat is I want it to be really tiny and really controllable.
>>
Eugene Dummlenudging - Sun, 16 Feb 2014 01:29:23 EST ID:H8L33pZj No.6143 Ignore Report Quick Reply
The easiest way would likely just be pneumatic/hydraulic cylinders, a solid one inside a hollow one. If you had a lathe you could make on precisely, if not, you might be able to make a demo version by like taking a circle pencil, and a normal plastic pen like a bic, then using a hairdryer or heat gun to wedge the pen along the pencil, and if you can keep rotating it you could form it to the pencil, then maybe to reduce friction further, VERY lightly sand the pencil (better if you have a pencil with some design painted on it so you can check sanding).

Then use a bit of oil to lubricate the pencil down the pen shaft, and maybe use a tube from a lighter to regular the flow of liquid/air inside the pen:
1) hot glue/plastic glue one end of pen shut
2) drill itsy bitsy hole, or just wedge metal tip from a grill lighter near base of pen
3) hot glue/plastic glue tube in
4) see if you can get enough pressure to slide pencil back and forth

It may be more optimal to use something more durable like surgical or aquarium tubing, or even another pen melted+welded to the first one at a right angle.
>>
Fucking Sollyville - Mon, 17 Feb 2014 12:33:44 EST ID:CKZoWqYh No.6144 Ignore Report Quick Reply
A quartz crystal
>>
Simon Noffingsock - Thu, 20 Feb 2014 02:49:46 EST ID:SB9ZYn17 No.6149 Ignore Report Quick Reply
>>6141
Sigh, are you trying to make a gravity wheel?
>>
Jack Nicklefield - Sat, 22 Feb 2014 23:33:13 EST ID:ICNMu9y9 No.6156 Ignore Report Quick Reply
so like you have your compass right
you hold down the contractor and levitate the mouse slightly above the mousepad
and all of the sudden you can remember where the buttons are without clocking out left to right like the variable expansion of a drag
Like what do you mean lengthwise it's a pencil if you wanna drag charcoal around all the time it's gonna squeal like deaf


electrician time by Nicholas Pockspear - Tue, 18 Jun 2013 20:39:42 EST ID:Trq6+u+h No.5760 Ignore Report Reply Quick Reply
File: 1371602382238.gif -(333911B / 326.08KB, 163x200) Thumbnail displayed, click image for full size. 333911
hey guys, i want to be an electrician

are there any recomended trade schools that i could attend that cheap/good educating/ect? i live in the nyc area thanks guys
2 posts omitted. Click Reply to view.
>>
Nell Worthingdock - Thu, 20 Jun 2013 02:23:33 EST ID:BSkmKEqx No.5763 Ignore Report Quick Reply
I thought all electricians did was bend pipes.
>>
you're welcome - Fri, 28 Jun 2013 18:47:07 EST ID:mCS3dD2d No.5773 Ignore Report Quick Reply
Apex Tech in Queens Plaza, for real is the best you're gonna get in NYC.
> http://www.apextechnical.com/index.htm
>>
Eliza Shakefuck - Tue, 02 Jul 2013 20:55:38 EST ID:BCwPed96 No.5783 Ignore Report Quick Reply
>>5760
Look into University of Delaware for Electrical Engineering. I'm currently going there for Mechanical Engineering and it is a great school.
>>
Lego - Mon, 17 Feb 2014 17:21:43 EST ID:6gKb6+Eq No.6145 Ignore Report Quick Reply
Move to moxxy/yakima washington. There's a tech school there called Perry technical institute. I believe it's about $30 grand for a 2 year program from electrician. They have a 100% employment rate too. There's a few hours of classroom time every day, followed by like 5 with hands on training. It's pretty much a full time job. The cost of living in Yakima/Moxxee is easily manageable though. I have a cousin who just got done with his program and had several job offers into good companies. The school even helps you build your resume, and they make it a point of setting you up with an awesome job, as it reflects back on their service. It would be a big life change, but I can definitely tell you that if you have time and money, it is by far one of the best places to educate you properly and set you up with an awesome career with room to move up.
>>
Nigger Blackleville - Tue, 18 Feb 2014 05:10:22 EST ID:BKcz5mkY No.6146 Ignore Report Quick Reply
>>5783
he wants to be an electrician not an engineer foo


MET vs ME by Fuck Chamblefack - Tue, 26 Nov 2013 01:15:59 EST ID:lu2Ug2u8 No.6013 Ignore Report Reply Quick Reply
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Whats the difference between a BSMET and a BSME? My local tech uni claims that their MET grads are 'engineers' but from what Ive read MET's are considered 'technologists'

(This school's ME program hasn't produced any grads yet and is therefor unaccredited)
2 posts and 1 images omitted. Click Reply to view.
>>
Augustus Puvingsit - Fri, 14 Feb 2014 11:57:47 EST ID:BKcz5mkY No.6136 Ignore Report Quick Reply
>>6014
This depends you can take the P.Eng exam and get your professional designation like that.

OP you need to really look into the program because it can get kinda tricky. In short, if a technologist diploma takes more than 3 years it's not worth it. I got 2 diplomas in 3 years, found a solid job, and then I went off to finish my degree at a university.

The school where I got my diplomas that offers a part time bachelors program, and it's all good and everything especially if you're working but it's not accredited, so you gotta take a ton of exams at the end.

I didn't go that route because I don't want to close my options in terms of graduate education.
>>
Augustus Puvingsit - Fri, 14 Feb 2014 11:58:52 EST ID:BKcz5mkY No.6137 Ignore Report Quick Reply
>>6135
I'm pretty sure that circuit will literally give you 0 output.
>>
Jenny Blatherhall - Fri, 14 Feb 2014 18:51:09 EST ID:UD9Q5Q+J No.6138 Ignore Report Quick Reply
>>6137
The output would be railed at 15V.
>>
Samuel Buckleheg - Sat, 15 Feb 2014 00:39:23 EST ID:BKcz5mkY No.6139 Ignore Report Quick Reply
>>6138
wouldn't the negative voltage on top and positive on the bottom fry it? is that why you're saying it's railed at 52?
>>
Edward Mangernad - Sat, 15 Feb 2014 13:37:02 EST ID:UD9Q5Q+J No.6140 Ignore Report Quick Reply
>>6139
He didn't specify which power pin the negative voltage is connected to. Even though the negative voltage is on top, we have to assume that it's connected to the negative supply pin, and positive to positive. For some reason he has the output of the 1st op amp tied to the negative supply on the left, so that op amp will get fried, but let's just say in a perfect world the power supplies have zero source impedance and can source an infinite amount of current. The input to the second op amp would be -15V, and it has a gain of -2, so the output is railed at 15V (minus a diode drop here or there, I forget).


Audio Electronics by Walter Greenway - Thu, 09 May 2013 10:25:57 EST ID:5EiDjcTO No.5631 Ignore Report Reply Quick Reply
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I would be very grateful if anyone with any knowledge of audio engineering could give me a hand here. Even basic electronic descriptions would be great.
Could someone please explain to me the purpose of Capacitors, Resistors, and other components within a mixing console?
I understand there's a total "we wont do your homework for you" and that's fine, but I'm struggling to find a description of what these components actually do when in the context of an analogue recording desk.
Thanks for the help guys, I'll probably try cross posting this in /m/ but I'm not sure about the expertise of the guys over there.
5 posts omitted. Click Reply to view.
>>
Graham Mevingwut - Thu, 23 Jan 2014 23:46:45 EST ID:SMgEF33p No.6104 Ignore Report Quick Reply
>>6102
>my 11th grade math teacher litterally said "dont bother asking me when you will use this, you still have to learn it" when we were talking about complex(imginary) numbers.

Sin(x) +Cos(x) have equivalent expressions with e^(a*x) . Every function can be represented with sums of sin and cos functions. It's usually easier to work with the exponential function, though. I think I fucked up the exponential function, but the point remains. Imaginaty numbers are cool beans.
>>
Simon Genderfield - Mon, 03 Feb 2014 04:39:36 EST ID:U0IJI7OT No.6112 Ignore Report Quick Reply
>>6101

What.

A power supply generally works like this:
-Firstly you have the diode bridge that makes a pulsating voltage of your AC sine wave.
-After that you have a condensator leveling the voltage out
-After that you have an IC which levels and caps your voltage on a certain value.

Filters in the power supply are mainly used to stop the pollution that these power supplies give to the rest of your electrical installation. These filters are a combination of condensators and inductors in series or parallel. Due to resonance they'll filter out a certain range of frequencies (Fourier analysis of the current/voltage signal tells you which frequencies fuck up the most).
>>
Simon Genderfield - Mon, 03 Feb 2014 04:42:44 EST ID:U0IJI7OT No.6113 Ignore Report Quick Reply
>>6112

Obviously there is a transformer to bring the AC voltage to a decent lower value, which I forgot to mention.
>>
Doris Cricklespear - Mon, 10 Feb 2014 22:12:36 EST ID:kU/b2Op8 No.6129 Ignore Report Quick Reply
>>6112
Filters are also used in D-Class amps, where a signal is converted to a digital pwm signal. the digital is converted back to analogue at a different voltage using a low pass of some kind.
filters dont need to be LRC circcuits, opamps do it as well or better, with a steeper frequency response and less phase shift. just fyi
>>
Eliza Semmlefure - Fri, 14 Feb 2014 06:37:04 EST ID:PDTgKfh5 No.6132 Ignore Report Quick Reply
>>5631
Go to khanacademy.com and watch everything in the Calculus and Differential Equations sections, then go to libgen.info and torrent a few EE textbooks.
Do you really think you're going to learn four years of EE in an image board post?
Granted you only really need to learn basic circuits, electronics, and signals, but if you're not willing to put in the time, you're never going to really understand what's going on.


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