/sci/ - Science & Math

[Anonymous No.5241354]

hey /sci/, what is some interesting, easy to do circuit for my lab project?
and no, i'm not an engineer, just a physicist that never cared much for circuits

I was thinking something like a remote control that could turn on or off some leds, but I don't have a clue on how hard would this be

[Anonymous No.5241393]

I assume as a physicist you are already familiar with the theoretical stuff like Ohm's law. But if you have never cared much for circuits it might be a good idea to read a bit about them first, here are a few suggestions:

http://www.wisewarthog.com/electronics/recommendations-practical-analog-electronics-books.html

Maybe the "Electronics Experiments" by Calvert (about at the middle of the page, in fact it's not a book but a website) are the most interesting for you.

And, of course, the classic: Art of Electronics by Horowitz / Hill.

[Anonymous No.5241400]

>>5241393
wow, thanks, this was the exact kind of post I was hoping for

[Anonymous No.5241931]

get some 555s, very versatile little timer IC, great fun to play with

[Anonymous No.5241996]

Better get an Arduino, the programming is very easy and you con focus on the electronics that you connect to it.

[Anonymous No.5242038]

zillions of circuit schematics: http://www.discovercircuits.com/

[Anonymous No.5242088]

>>5241354
Have you considered a career in analogue electronics? As a physicist you should have an advantage for real world interfacing to electronics which often is analogue.

Digital electronics is simpler to learn and also to teach. This has caused a world wide shortage of skilled analogue electronics experts. Further specialisation in high speed analogue or RF analogue or low noise analogue would mean you will never worry about getting a job.

[Anonymous No.5242136]

>>5242088

Digital or analogue, doesn't matter, all the jobs will go to India or China.

[Anonymous No.5242146]

>>5241996
I'll probably take an arduino/similar stuff course next year, so I don't want to use something that complicated yet.

[Anonymous No.5242166]

>>5242136
Perhaps. Then again analogues electronics expertise is scarce there too so you can still get a really well paid job there. For all the problems with China and India, they still have a respect for educated people.

In a previous job the manager had tried to "save" money by reducing salaries to two analogue designers, thinking they were over paid. So they left. And the company got into serious trouble. Too late the boss realised that there were really, really good reasons for the high salaries: getting replacement designers turned out to be hard and it killed the timetable for product launch. Most likely this was the root cause of the collapse of the entire company.

[Anonymous No.5242211]

Operational amplifier. or make a traffic light circuit with 3 leds and timers. or do some basic things with logic gates.. or count up in binary with leds or something

[Anonymous No.5242307]

>>5242146

It's OK if you prefer to use the Arduino when you have the corresponding course. But you should not assume that there is anything complicated about the Arduino. Quite the opposite. The Arduino development environment was created with the intention that even fucking ARTISTS could use it. The average artist is dumber than a hamster, yet he can learn to program the Arduino ! Designing electronic circuits is much more difficult.

[Anonymous No.5242354]

Me and a friend built an audio sequencer with two 555 timers and a 4017. Shit was fun to build and I learned alot.

[Anonymous No.5242391]

>>5242307
ok, maybe I'll give it a look, but the project is due in like 2 weeks, so I can't promise anything

[Anonymous No.5242395]

>>5242354
that sounds fun, thanks

[Anonymous No.5242543]

ARRL has plenty of books for RF electronics experiments as well as kits.

[Anonymous No.5242591]

Distortion pedal! They're pretty simple; you can make them with just a few basic components and a solderless breadboard.

[Anonymous No.5242625]

get a box of 2sc2879 transistors, build massively overpowered 11 and 10 meter linear amplifiers, sell at truckstops for cheap, make a shitton of money.

[Anonymous No.5243002]

>>5242591

Solderless breadboards suck. Learn to use a soldering iron, lazy nigga !

[Anonymous No.5243062]

>>5241393

Best book's missing from that list, and that's "Getting Started in Electronics" by Forrest Mims. Get this !

[Anonymous No.5243082]

8 step sequencer?
http://youtu.be/rR9tFKMrAFs

[Anonymous No.5243556]

>>5243062

this.

[Anonymous No.5243922]

>>5243002

For a lab project solderless breadboards are fine, as long as the involved frequencies are not too high.

[Anonymous No.5244404]

check out Afrotechmods

[Anonymous No.5244768]

>>5242391

you can't learn electronics in 2 weeks

[Anonymous No.5245486]

Educypedia has links to many circuits:

http://educypedia.karadimov.info/electronics/circuits.htm

[Anonymous No.5245542]

>>5241354

Make an EKG. It's a lot easier than you'd think, and it has the cool benefit of producing cool waveforms on the oscilloscope even with relatively crappy circuit components.

[Anonymous No.5245618]

>>5245542

just make sure you don't electrocute yourself

[Anonymous No.5245639]

>>5245618

This is true. Definitely buy the legit sticky pads with the leads, they're probably safer if you do shock yourself.

Although, unless you seriously fuck stuff up, the op amp configuration should make it literally impossible for any current to come back on you with an EKG.

Also, don't forget about that pesky 60 Hz wall power noise.

[Anonymous No.5245642]

>>5241354
Electronics engineer here. If you want to do radio control you can get a pair of RF transceiver modules from Sparkfun and a microcontroller (arduino is good for hobbyists). Or you could be hardcore and design your own radio control circuits.

I'll start with the receiver end. A radio control signal is some tone carried on a carrier wave. You build an LC circuit to pick up the carrier wave from the anteana. The LC resonance needs to match the frequency of the carrier wave. The anteana should be about half the wavelength of the carrier wave. Now to pick out different tones you need a bandpass filter, which is an opamp combined with some capacitors and resistors.

On the transmitter end you probably want to generate your carrier wave with a crystal oscillator. You can generate tones with a 555. Combine the signals with an analog adder. You want to push the modulated signal into an H-bridge r half bridge circuit to increase the power, although that isn't even necessary if you don't need a lot of distance.

[Anonymous No.5245656]

>>5245542
I built one of those as a project in second year EE. Its not as simple as just building an amplifier to pick up the signal. I had to build four stages of filter circuits before the output looked better than static.

[Anonymous No.5245682]

>>5245656

Yeah, I've made one too way back in instrumentation class. I took the output and filtered it digitally. If you do it that, it really is basically just picking up the signal through a differential op amp to subtract out the environmental noise and then amplifying.

Idk, with my materials some pretty simple digital filtering produced fairly nice data. They weren't pretty, but they were obviously EKG waveforms.

[Anonymous No.5245690]

>>5245656
do you have any advice or pointers? I'm in CS and would like to build an EEG (not too different I imagine (+ complexity)) for prosthetics. I'm gonna research it more thoroughly, but do you have any tips on what to consider that would otherwise be left unconsidered, etc? Is there any specific literature you could reccomend?

[Anonymous No.5245783]

>>5245690
I've uploaded my old project report.
http://www.crocko.com/C25BCADEFBCC4ECDBA91E005D3853071/Grp10-Md3Report.pdf

You might need to wait a few minutes before its available for download.

[Anonymous No.5245853]

>>5245783
beautiful, many thanks anon.

[Anonymous No.5246260]

>>5244768
I'm partners with some more experienced guys, I just want ideas.

[Anonymous No.5247848]

Some very easy circuits with detailed explanations:

http://www.allaboutcircuits.com/vol_6/index.html