Basics...

[Cyanmonkey]

I'm trying to find ways to understand electronics theory without having to pay for any sort of classes. If anyone's got any sort of reading I can do to understand it...

Bascially, I understand impedance and that stuff and can essentialyl read a schematic (yeah, I'm really new to this), but I wanna know why you'd put a 1k resistor in a circuit as opposed to any other.

 

[Larrchild]

Because a 10 000 ohm resistor would "resist" the voltage more than you need. And a 100 ohm would "resist" less than you need. Using Ohm's Law, while desiging would tell you.
http://www.the12volt.com/ohm/ohmslaw.asp

 

[Cyanmonkey]

i understand that, but i'm curious about how you find out what resistance you need in the first place.

how do you design the circuiut for an amplifier?

 

[Larrchild]

Well..... You read a book on amplifiers. Then you get a general idea of what goes where. Then.... You refine that knowledge by using Ohm's Law to define what voltages and currents you want to appear where.

 

[Cyanmonkey]

makes sense. got any books in mind?

 

[northsiderap]

This site is a good read. Google any phrases that you get stuck on. Print it out and read it multiple times with a pen, paper, and calculator in hand.

http://my.integritynet.com.au/purdic/rf_amp.htm

Lots of links here too:

http://www.electronics-tutorials.com/

Scroll down a little, and on the left hand side there's a lot of info.

 

[CJ]

Actually, a beginning course in electricity or electronics is your best bet.
You might look around the JC's in your area and see what they have.

also, check the Electronics 101 in the Meta, which I am still feeling the guilt on for part two.

We could walk you thru from A to Z but that would take a long time doing it like this.

 

[Clayphish]

I'm pretty green, but I have to say a good place to start is the library. Just get a few books on the same subject so you can use them as cross references if you have any difficulty with theory. So far it's been very helpful for me, anyways.

 

[Andre]

Cyanmonkey,

Having no formal electronics training I'm find myself in the same boat.
I always feel like I'm not part of club whenever I don't understand what's going on. And those who do understand are rightfully proud of their knowledge.

Typically I consider that there are 3 things to know:

1. Theory - The general why/how stuff works.

For this I suggest this book for < $20:
http://search.barnesandnoble.com/booksearch/isbnInquiry.asp?z=y&isbn=0760752397&itm=1

2. Detailed Design - eg. Using a spec sheet, how do I know which resistance will provide 35 dB gain using a XXX opamp?

To answer this I would first formulate the right question and then get someone on this board to show some example calcs. Although to truely understand what's going on, I think you'll need to build test circuits and prove to yourself that the math works. Having the equations in front of you isn't enough.

3. General Design - eg. I want to build an opamp of my own design from scratch.

Of course this is hardest thing to grasp since it requires years of experience. I think we'd all like to be the next Rupert Neve, but the fact of the matter is that a successful circuit will always mimic something that alread exist. Improvement in general design comes to us after years of building and pondering over countless pages of schematics.

The idea is quite simple: Copy and modify. After some time you'll end up with something unique.

This is my $0.02. Should you find the route to instant knowledge, please do share it on this board.

Regards,

- Andre

 

[Cyanmonkey]

yeah, i'm looking forward to screwing up again and again until i get it right. i'll get it...i'm all about trial and error. i'm glad i happened upon this forum.

 

[Ptownkid]

http://www.opamp-electronics.com/

 

[Clayphish]

Awesome site ^^^