I'm trying to make a simple tDCS but can't find all the materials online
Will something simple as this work? I will put wet sponges on the end to avoid burning my scalp
Do it with 1000 volts and 100 amps If you want to get super smart.
yeah, it'll work, but it's not super-duper safe. suppose you had scratches in the skin below the electrodes; that would increase the current by many times compared with unbroken skin.
you wanna have, at minimum, a fixed resistor in series to limit current. or better yet, use a constant-current generator so you have a very well controlled maximum current flow.
>>977708
don't do it, i looked into this a few weeks ago and it is not worth it.
It speeds up your reaction time a little but your fine motor skills diminishes.
>>977737
>so you have a very well controlled maximum current flow
That circuit of yours doesn't really produce very well controlled current, as it does not take LM317's own current consumption into account. You might get several milliamps more than you're expecting, depending on IC and luck.
>Milliamps
>Through skin
>9 V battery
I just stuck two probes to my forehead, and there's about 2 megaohm across my head.
Perhaps I just have a naturally high resistance toward snake oil. :^)
>>977775
> 2 megaohm across my head
did you read this part in the OP, retard?
>I will put wet sponges
>>977775
You need real electrodes with relatively large surface area and probably proper skin preparation too, mr. Oil Skin.
>>977708
>wet sponges
no. it needs to be a dielectric goo. you are trying to send a signal through the tissue not just short out a 9v battery on your tongue.
Use paste dental over skin
What a bunch of fucking idiots, I hope you get two ugly scars on your temples as a brand of shame. Is this sort of bullshit really accepted here on /diy/? It's like starting a thread on "free electricity from the ether" on /sci/.
Am I the only one who noticed that the arrow indicating current flow in OP pic is backwards? I thought this was going to be bait, but everyone is taking it so seriously.
>>977868
it depends if you're looking at flow of charge or charge carriers, they can both be right just looking at different things.
Thinking fast is already tiresome enough.
In all honesty, i don't think it would directly flow through the brain tissue but rather along the skin and if it does then it would only make sense to me with very low frequency signals.
>>977865
At least this is something that can be built. It might be as pointless as trying to deliver canabis via intraocular route, but if these guys want to electrocute their brains for fun I say we sit back and enjoy the show.
>>977865
Why not? If some dummy wants to shock his head, I'll help him out.
>>977897
Anecdotal evidence is necessarily not placebo controlled.
>>977897
[citation needed]
Just pick one of these off ebay. Make sure it includes the little red rubber thingy, you need that.
>>977708
>9 volt current source
>volt current
stopped reading, now just have a shit eating grin.
Ok op, continue with your project. Be sure to keep us updated and let us know before you try it out.
>>977737
so you plan to electrocute the part of the brain that deals with logic and reasoning?
>>977902
>>977911
>>977902
>>977911
I didn't feel like citing the sources as I was at work, too busy and wouldn't have been able to find the original articles I read. But here are similar ones.
http://www.scientificamerican.com/article/amping-up-brain-function/ <----- This is similar to the radio interview I listened to a few years back, only the interview used a military firing range simulation
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3766817/ <---- A neurosciences paper discussing the ethical use of tDCS in the military and several references of its use in clinical studies in psychiatry
http://adifferentdrum.org/my-brain-on-electricity-a-130-day-tdcs-experiment/
And a whole slew of others are out there. The fact is that electric shock treatment has been used in psychiatry for decades, both in excess and in small amounts with a range of different effects, from the erasure of memories to benefits from disorders such as depression.
I am not saying that a home brewed one is safe, or even that the purchased ones are, just that there are a lot of studies that have been done by the military and by medical industries that show the use of tDCS or similar technologies do a lot more then just "speed reaction time" or "think faster"
>>978176
You are gleefully waiting for updates you won't get because OP will be dead.
>>978277
>the joke
------
>your head
>>978176
And what exactly is wrong with saying "9 volt current source"?
>>978296
A current source is independent of voltage.
>>978297
Obviously.
So why wouldn't "9 volt current source" mean "a device that provides current and also has a potential difference of 9 volts across its terminals when it provides current"?
i wanted to write several paragraphs on how stupid hooking live current to your head is, but if you're stupid enough to fall for such an idea, you're too stupid to take in anything other people say.
enjoy natural selection.
>>978341
semantics
i can't be arsed to type out a full explanation, but basically voltage source (constant potential maintained regardless of load/current) =/= current source (vice versa)
you can't have a constant current while maintaining a constant potential with a dynamic load
so ohms law
>>978347
I fully agree with you.
Now if you take a look at OP's picture, it says "9 volts current source" which one can easily decode as "a device capable of supplying undefined current at 9 volts". It isn't hard to imagine such a device, is it?
>>978351
no because current source by definition means fixed current ie not undefined current. that would be a voltage source
>>978354
It's a matter of general definitions vs technical jargon. If you're designing a device you should use the correct terminology, even if the general usage of the word would be grammatically correct.
>>978362
It would be like if someone drew a diagram labelled 'crank shaft' and then talked about how it used eccentric cams to control the valve timings.
Can we figure out that they meant 'cam shaft'? Sure, but they still used the wrong word on the diagram.
>>978362
The picture just dropped "battery" from 9 volt. So 9v current means a current from a 9 volt battery, not "volt current". It's how I read it anyway, just lazy grammer.
>>978351
I'm the one that said its wrong.
it doesn't specify what current, and any current would be bad. If it wants to take into account current and voltage then it should do so. 9 volts dc will not go through the skin. but if it did and any current was allowed, it would caust bad stuff to happen to the body.
as someone else said, volts and current are independent of each other. its like saying a 50kmh/mph psi source. it just fucking sounds stupid and doesn't show anything.
>>978283
I got the joke. I was doing the "let's make the joke really obvious routine." Partly because I want to rub in that OP is a moron.
>>978405
The current from a 9v battery will depend on what it's connected to. In this case he wants to connect it to his BRAIN. From his phrasing it's clear that he doesn't know how much current his brain will draw and especially doesn't know how much would be drawn from a 9 volt battery. It's not just that the terminology is lazy/ wrong it shows underlying egregious misconceptions about electricity. Which you know what? It's fine to not get electricity, a lot of people don't. But when you don't know anything about electricity maybe your first potential project shouldn't be trying to send a current through your brain.
You know what would infinitely make you smarter? Picking up a book and reading about electricity first. And then picking up and reading 3 more because you'll think you're hot shit after the first and need to read more before you realize you don't know jack.
>>977868
Current is said to flow from positive to negative because in early electricity people didn't quite understand the mechanics and arbitrarily chose a direction. It wasn't until later we discovered electrons flow from from the cathode to the anode. Even so "current" still flows positive to negative, opposite the flow of electrons.
Or so I read.
>>978405
I'm not sure if you already know this, my apologies if you do, it should still be a good description for anyone reading the thread that's confused.
While in English, 'Current source' grammatically means 'A source of current' in technical jargon it has a more narrow definition.
In terms of electronics jargon '9 volt battery current source' would still be incorrect since a battery is a voltage source due to its cell chemistry. It's a voltage source because it delivers the same voltage (neglecting internal resistance) regardless of resistance, this means that the current changes as you vary the resistance of the circuit.
A current source requires additional components for regulation, so it can't just be a battery.
A current source outputs the same current regardless of resistance, this means that the voltage changes as you vary the resistance in the circuit.
On the diagram posted here >>977737 all the components on the right side of the diagram can be grouped together and referred to as a 'current source'. If you see a current source symbol on a diagram, that symbol represents a group of components with that function.
While in this case the OP could still be understood, there are many cases where using the incorrect word for your power supply would completely change the function of the circuit. For example, if OP hadn't included a picture of a battery, it would have been assumed that OP had already built a circuit that was functionally the same as >>977737, resulting in potential injury.
I know this might sound like it's just an autistic rant, but I wanted to clarify why terminology was important in a way that people wouldn't immediately respond to with "Well we know what he meant, you're just being a pretentious dick".
>>978454
>I want to rub in that OP is a moron
I dont appriciate you fucking up natural selection.
now think for a moment, one day youll have a daughter and now op will live long enough to have a son who will impregnate your daughter.
look what you did.
>>978458
For those of you who like the water analogy, batteries (voltage sources) are like a pump that supplies a constant pressure (psi) regardless of the diameter of the pipe. If you have a wider pipe, you will have a greater flow rate (L/min) than a narrower pipe.
A current source is like a pump that has a sensor to monitor flow rate and raises or lowers the pressure (psi) such that the same amount of water (L/min) flows through the pipe regardless of how wide or narrow it is.
A sudden decrease in resistance can be imagined as a the pipe bulging to a wider diameter, in this example the constant pressure pump will keep increasing the flow rate to maintain pressure in the system. A constant flow rate pump on the other hand will decrease the pressure to keep the same rate of flow.
If you were using the system to fill a container when this happened the constant pressure pump would start filling the container much faster. The constant flow rate pump would continue to fill the container at the same rate.
Stretching (to ridiculous levels) this analogy to OP's situation you can see that if the resistance of the circuit decreases (due to changes in skin hydration, skin integrity, ect.) we can imagine that as the pipe bulging. When this happens, if you have a constant pressure (voltage) pump attached to the system you will suddenly dump water (electricity) into OP's head much faster than we intended. A constant flow rate (current) pump however, will continue to deliver the amount of water that we intended it to.
>>978465
>one day youll have a daughter
Jokes on you, I also frequent the outcasts of society boards. I'm not having any kids. It's 9 pm and do you know what your daughter is doing, buck-o?
>>978498
I grow less and less appreciative of the general use water analogies with electronics as time goes on. When applied to something like a capacitor it only works in an abstract sense because the behavior of charge in a capacitor has no analog in the movement of water.
>>978674
I dont have a daughter but if I did she would be gps tracked.. so yea I would, fuck-o.
>frequent outcasts of society boards
what the fuck are you even trying to talk about?
>>977865
You can get free electricity from the ether?
OP's bastard daughter of a whore here. Yeah, daddy shorted out and is a vegetable now.
>>979292
Well I suppose if you found some free ether like that other OP then you could burn it...
>>977897
>Judy your reaction time
I've always wanted Judge-Judy levels of rain!
>>977777
OP, some things are best left to a team of highly trained professionals.
