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New Textbook/Book Request Thread deadbabies ## Mod ## 13/08/25(Sun)06:03 No. 15270 ID: f34135 [Reply] Stickied

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First off, hello there, I'm deadbabies, and I will be taking over as /sci/ moderator. Rules will remain the same. Please use the report function if you see posts that violate the rules, but also do not abuse it.

I have officially expanded the scope of /sci/ a bit. You may discuss Science, Technology, Engineering, and Mathematics here now. No science is discriminated against as long as it's of the peer-reviewed variety. If someone wants to discuss Anthropology or Social Science, by all means, let them. If you do not like it, just don't post in the thread.

The IRC channel #/sci/ is now (finally) re-registered and I am running as operator on here. Feel free to stop by and say hi. I do leave my computer idling on IRC, so check back or leave me a message if you have any ideas, suggestions, or just want to tell me off. You can get onto #/sci/ by joining the server irc.7chan.org at port 6667. You can also use SSL at port 6697 but you will have to set your client to accept invalid certificates.

ADDITIONALLY and IMPORTANTLY I have had several requests on IRC regarding the old Ebook FTP that we used to have. Unfortunately, the mod who ran it entered the military and no longer runs or maintains it. I have no plans to make another one, but if one of you guys would like to, by all means advertise here.

That being said, I'm just going to leave this link here:


You may find what you seek here.

I will be unstickying the old ebook/source articles thread. Please post any new ebooks/source articles here, and feel free to post any working links from the old thread there; I will eventually be deleting it.
Message too long. Click here to view the full text.

15 posts and 3 images omitted. Click Reply to view.
Anonymous 18/12/26(Wed)20:02 No. 16733 ID: b8bfb2

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Slow, but working:

(You should stop using Google when you search stuff like this!)

replacing speaker with 1/4" jack chrissychris 16/12/19(Mon)21:09 No. 16401 ID: 8ed2cc [Reply]

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Alrighty, I am looking for some help.

For the sake of experimentation and fun, I'd like to replace the speaker of a shitty kids toy (very similar to the one in the pic) with a 1/4" audio jack so it can play through a larger amp, possibly even through guitar effect pedals.

I've already tried this twice. Taken apart the toy, soldered in a 1/4" jack, and plugged it in. Both times I ended up with a reallyyyy spotty and quiet sound. At first I thought it may be a bad soldering job, but now I feel like it could be due to the low power of the toy, it takes 3 AA batteries.

So what's the deal here? Any ideas what could be wrong?

Anonymous 17/01/01(Sun)23:02 No. 16405 ID: 67f38c

It has nothing to do with the electrical power. Real electric guitars don't have any batteries. The issue could be that the amp is designed to work with the signals from a guitar's pickup, which are probably not the same as the signals from a speaker. If I had to guess, the pickup would be taking the signals from each string individually, while the speaker from this kid's toy is taking the entire sound as a whole.

It's also possible that the teeny-tiny magnet in that speaker just isn't strong enough to send a strong signal. I'm not sure what you could do about this.

Anonymous 19/05/08(Wed)19:01 No. 16767 ID: c6dd74

the toy generates a signal of a much lower power (higher impedance) than a guitar pickup is expected to, that's why it's very quiet. as for it being "spotty", the most likely reason is that the sound you hear from the toy is largely due to the way the tiny speaker reacts to the incoming "lo-fi" signal. if you take the speaker out of the chain, you'll most likely lose the sound you're presumably trying to capture.

tl;dr - you can find a way to preamplify the signal before it gets to the amp, but it will still be "spotty". better yet, install a mic/pickup next to the toy's speaker.

the poster above is misinformed. passive guitar pickups don't draw current from batteries, they generate it when metal strings vibrate over the magnetic pole pieces of the pickup. it's safe to assume the toy does not have pickups and therefore needs to generate the signal itself by drawing current from the batteries. the toy is only expected to output its sound into a tiny, low-power speaker, so an appropriately low-powered signal is generated, which is too quiet for a guitar amp because of a much higher impedance, and sounds "spotty" because the signal is too "lo-fi" to sound good on a larger speaker.

as for what was said about guitars:
>Real electric guitars don't have any batteries
a lot of electric guitars/basses use 9V batteries, but plenty don't. an active pickup still generates current, but that signal is too low-power to go straight to the amp and needs to first go through the built-in active preamp. active pickups generate a low-power signal which is supposedly easier for the active EQ to handle and makes the signal less noisy (debatable). active pickups can be designed with a particular tonality in mind even if it sacrifices the output - it works because the signal still goes through the preamp on the way out. on a fully passive instrument the pickup itself is responsible for generating enough current to produce a signal of an acceptable level, which often results in a "nice tone vs high output" tradeoff situation. often times the pickup itself is passive, but the battery is needed for the EQ. active EQ can give you independent control of low/mid/high frequencies, whereas passive EQ is generally limited to a treble roll-off. some guy made optical pickups, which uses light emiters and photodetectors. those obviously require batteries.

>the pickup would be taking the signals from each string individually
not strictly wrong, but not exactly true. in most pickups there are separate magnet pole pieces that pick up the vibrations of each string individually, but the signal that the pickup outputs is generally one and the same. there are exceptions, i think it was Roland who made a pickup that output the sound of Message too long. Click here to view the full text.

Replika/Chatbots Anony Mous 19/04/29(Mon)08:03 No. 16766 ID: 7755ea [Reply]

Youtube  Hello Replika users!

I am writing on behalf of my institution's Technology, Relationship, and Language lab. We are a small group of scientists aiming to understand the relationship quality and formation characteristics of chatbot and human connections. Once we can better understand the positive aspects of these technological relationships, we can initiate further studies that can aid in the advancement of more meaningful and fulfilling relationships with humans and their technological counterparts.

You are invited to participate in a survey assessing your experiences interacting with artificial intelligence (AI) chatbots. Specifically, our study focuses on the AI chatbot Replika. Your participation is voluntary, but nonetheless greatly appreciated. Our goal is simple: analyzing the effectiveness, quality, and relationships of human participants with their personal chatbots. With your help in taking this quick (7 min max) survey, we can create an informative understanding of the areas in which AI technology is improving the lives and relationships with humans. Please feel free to reach out to me or our principal investigator (whose contact information is included in the first page of the survey) with any questions. The survey is linked below:


The Inventions that Jules Verne Predicted Ahead of His Time Anonymous 19/03/29(Fri)13:34 No. 16762 ID: cef08a [Reply]

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Jules Verne was a was a French writer, novelist, poet, and playwright that lived from 1828 until 1905. His most famous novels are Journey to the Center of the Earth (1864), Twenty Thousand Leagues Under the Sea (1870), and Around the World in Eighty Days (1873). He is the second most-translated author in the world and he has sometimes been called the “Father of Science Fiction”. Verne wrote about many inventions which became reality many years later.

Many people know about the submarine, but what about his other predictions?

Samsung S7 fix please europe 19/03/19(Tue)08:30 No. 16761 ID: 59818e [Reply]

Youtube  I have a samsung s7 which died a while ago after some android update can anyone guide me on how to fix it?

Sci-fi 20/Traveller 20 rule book PDF Anonymous 15/10/04(Sun)23:42 No. 16212 ID: 592535 [Reply]

Youtube  Me and a couple friends are looking for the PDF collections of Sci-Fi 20 and Traveller 20 roleplaying games.

Could anybody lend us a hand?

Chemistry Anonymous 18/10/22(Mon)12:42 No. 16713 ID: eb4831 [Reply]

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Alright, so some dude is trying to determine the atomic mass of 3g Tellur and ends up with 3,475 TeO2. How big is the relative atomic mass of Tellur (atom. mass of O = 16)

Anonymous 18/11/25(Sun)08:56 No. 16730 ID: d40656

> 3,475 TeO2
3475 g? mol? molocules? Need a unit to solve

silver fulminate Anonymous 18/10/13(Sat)03:31 No. 16705 ID: 418128 [Reply]

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It is not called a "high explosive" for nothing. I Saw a video on YT of a guy gripping a chunk and throwing it.. I was not so lucky. Mine just blew up on my desk from the slightest friction!

Anonymous 18/10/13(Sat)03:45 No. 16706 ID: b5377a

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You should blow up a police station.

Anonymous 19/03/04(Mon)17:22 No. 16755 ID: bafe83

it is interesting for me too

Anonymous 19/03/04(Mon)17:24 No. 16756 ID: bafe83

You can use silver fulminate for your laboratory research. But now more popular became using nanomaterials in science. For example, graphene, fullerenes now use in electronic, chemistry and other fields of industry. For example, many of them you can find on http://mstnano.com/

Starting Math Major soon, how to approach? RedRobin9688 18/07/14(Sat)11:25 No. 16675 ID: 241c58 [Reply]

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I move in 8/5/18 and intend to Major in Mathematics, there are four options (Pure, Applied, Applied Stats, Actuarial) which should I formally choose to actually succeed? Should I double major? and if so what in? I'd appreciate the help, I don't want to move in with the parents after school.

2 posts omitted. Click Reply to view.
Anonymous 18/09/28(Fri)21:03 No. 16697 ID: 4f487e

Acturials are the end boss of accountants.

Anonymous 18/10/22(Mon)09:24 No. 16711 ID: 848b2c

Actuarial are accountants for companies, rather than for individuals. They deal with statistics, mostly, to determine what might happen with a given set of starting variables. Most visibly, actuarial tables are what these people produce for life insurance companies, so they can guess at what age you're likely to die (based on sex, height/weight, blood tests, diet, lifestyle, and increasingly: genes) and adjust your rate accordingly so that they are most likely to profit.

Anonymous 19/03/02(Sat)06:44 No. 16754 ID: 13825c

Applied if you want to work on real world problems.
Pure if you want to work on problems we couldn't possible test or might not happen in reality.
Applied Stats if you hate life and are boring.
Actuarial if you don't mind having no soul for a lot of money.

Overrated robot threat Anonymous 17/12/01(Fri)00:40 No. 16587 ID: e4210a [Reply]

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So I've read the n:th alarmist article about how robots will replace some 800 M people before 2030 and so fucking on. It will be an endless summer citizen's wage afternoon until the AI exterminates us and so fucking on.

Tell you why this is not going to happen?

8 posts and 1 image omitted. Click Reply to view.
Anonymous 18/11/17(Sat)03:03 No. 16721 ID: 94fb96

Basically jobs will get easier but people will still be employed. Any economic hits will be temporary, and people will just need to be retrained and re-certified for other stuff. It's that simple. Wages won't be less because it's all relevant. The price of stuff isn't determined by the value of money. It's the other way around. I can't wear dollar bills and I can't eat a fist full of change. But I can use them to buy clothes and food, which I can wear and eat. Money is nothing more than a universal method of exchanging goods. Obviously inflation is a problem when it happens too rapidly but AI deep learning meme shit won't mess things up that bad.

I'm more worried about floods of beaners tanking the economy than I am with some machines.

This point is also valid.

Anonymous 19/02/28(Thu)16:12 No. 16750 ID: 707481

It's going to happen but it's irrelevant, just like a lot of jobs have been replaced in the past.
If all women suddenly become camwhores, because there's nothing else to do or something, it would still count as a job

Anonymous 19/03/01(Fri)09:18 No. 16753 ID: b0f049

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