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Mimic a Remote's IR Code by Faggy Febberput - Thu, 27 Mar 2014 01:47:11 EST ID:FABnkK5n No.6232 Ignore Report Reply Quick Reply
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My goal is to make a little circuit with an IR LED that can function as the original remote. So I need to somehow "learn" that original code from the original remote and program that into the circuit.

Is this possible? I know that a hacked PSP can do it.
1 posts omitted. Click Reply to view.
Jenny Clammerfork - Thu, 27 Mar 2014 21:32:21 EST ID:FABnkK5n No.6234 Ignore Report Quick Reply
How do I record each code and assign it manually?
John Blenderlune - Fri, 28 Mar 2014 22:44:02 EST ID:vXg79lPA No.6235 Ignore Report Quick Reply
You need a microcontroller and an IR sensor. And an IR LED. And a power supply. And some very minor signal conditioning.
Frederick Depperhall - Sun, 30 Mar 2014 01:41:43 EST ID:xZgv+GY1 No.6236 Ignore Report Quick Reply
do you have the original remote?

if you do you can press the button and receive it in the other end with a circuit

the circuit is kinda involved, but it's easy if you're willing to learn

basically the signal is gonna come in as a square wave and you're going to have to grab that bit by bit, and turn in into a word, how ever long it might be.

i can't imagine the remote outputting more than 16 bits of information per button but i could be wrong, testing something like that might require an oscilloscope, but you might be able to find one at a hackerspace or something

to turn it bit by bit to a word you need something that's called sipo shift register which stands for serial in parallel out shift register. you might need a clock for one of those as well, and the clock speed might need to match the speed of the remote output though if you're clever you can get by that with a microcontroller or some clever circuitry but i'm not getting into that

and the output of that goes into a data buffer
Comment too long. Click here to view the full text.
Basil Dezzletig - Mon, 31 Mar 2014 08:38:40 EST ID:+llB3/RB No.6237 Ignore Report Quick Reply
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There is a lot of various circuits
Simplest build is like 5 parts
Software will take care of the rest
Sidney Clenkinweg - Tue, 01 Apr 2014 13:51:36 EST ID:DPsZhwc3 No.6238 Ignore Report Quick Reply
Well I give up.
Thanks anyway though!

Chinese 60 years behind the space race by Hedda Creffingdock - Mon, 10 Feb 2014 09:18:46 EST ID:9tRAlAIb No.6126 Ignore Report Reply Quick Reply
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Why did the Jade Rabbit moon rover fail /tesla/ ;_;


Trap card: Most of the Chinese engineers who developed it would have got theirs Masters and Docotrates from American Universities. I'm looking at you, Cal-Tech. and UCLA
Hedda Creffingdock - Mon, 10 Feb 2014 09:20:18 EST ID:9tRAlAIb No.6127 Ignore Report Quick Reply
1392042018891.jpg -(6456B / 6.30KB, 292x172) Thumbnail displayed, click image for full size.

*their Masters and Doctorates in Engineering from American Universities
Archie Buzzman - Thu, 20 Feb 2014 20:29:42 EST ID:Oq2QBNL1 No.6152 Ignore Report Quick Reply
why would they make a robot, powered by sun light, that can not turn on when its solar panels are collecting sunlight?
Graham Honeyman - Fri, 21 Mar 2014 22:38:15 EST ID:nSEO9O+z No.6222 Ignore Report Quick Reply
>During this time temperatures plunge to -170 degrees Celsius (-274 degrees Fahrenheit) and Jade Rabbit – which is powered by solar panels – must enter into a hibernation state to preserve its core systems.
Why the fuck would extreme cold hurt it? Preserve it's core systems? The dragon that powers it? Can't it boot up again after gathering energy after the lunar night?

>"If this journey must come to an early end, I am not afraid. Whether or not the repairs are successful, I believe even my malfunctions will provide my masters with valuable information and experience.
Yeah, maybe not to write half assed buggy software next time? Just making guesses...
Augustus Dummermetch - Fri, 21 Mar 2014 23:04:23 EST ID:5IdDtd2q No.6223 Ignore Report Quick Reply
space grade dragons and electronics alike are usually just not made to resist those low temperatures. or should i say, resist very low temps too good? get it?
Hugh Chosslefield - Tue, 25 Mar 2014 11:01:01 EST ID:TLtnKWTx No.6231 Ignore Report Quick Reply
I feel bad for the midged inside

Metal Wire Coating by Ernest Pockville - Sun, 23 Mar 2014 14:28:35 EST ID:uEfymhfr No.6224 Ignore Report Reply Quick Reply
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I'm trying to connect two different USB cords together, but one of them has this metal coating.
Is this a 5th contact or what does it do?
Shitting Pammerman - Sun, 23 Mar 2014 23:16:50 EST ID:2POYse6P No.6226 Ignore Report Quick Reply
it's the ground.
Nigger Nonkinnatch - Mon, 24 Mar 2014 01:06:26 EST ID:uEfymhfr No.6227 Ignore Report Quick Reply
Sir, I think the black wire is the ground
John Dartfield - Mon, 24 Mar 2014 13:47:20 EST ID:gxnGDEmu No.6229 Ignore Report Quick Reply
it's the shielding which is connected to ground?
that stops radio and other signals from interfering
Nigger Nonkinnatch - Mon, 24 Mar 2014 14:16:11 EST ID:uEfymhfr No.6230 Ignore Report Quick Reply

Space Station 13 by Lillian Beblingdudging - Thu, 05 Sep 2013 06:09:36 EST ID:qcML6joZ No.5879 Ignore Report Reply Quick Reply
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There is so much engineer in this game, I don't think I've seen so much engineer in a game since Team Fortress 2.

So much engineer, so many Practical Problems.
Priscilla Turveyville - Mon, 09 Sep 2013 21:35:02 EST ID:KFZ9rgNf No.5889 Ignore Report Quick Reply
Doris Dartworth - Sun, 16 Mar 2014 09:09:46 EST ID:RG6LVbQe No.6221 Ignore Report Quick Reply
420chan now has its own SS23 server.

So Engineer
very practical problem

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
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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
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
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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
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.

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
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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
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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.


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
>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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>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
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.

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
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

>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
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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
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
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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
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
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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
>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
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

please do so

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