Building from scratch/schematics

[breakitdown]

I was wondering how do you guys just create a schematic for something like an overdrive from scratch? I've seen a few posts of peoples ideas I just wouldnt know the first thing about where to start. Does anyone know of a FAQ or write-up where I can learn more about the electronics side of the building rather than just reading other peoples scematics and modding them? I'd like to have thhe know how to write my own schematic without total chaos. Any basic rules of thumb???

Matt

[vdm]

Here is a thread posted by Jay Doyle a while ago about using a mosfet driving a jfet, to create some nice overdrive similar to jake nagy's Blue Magic.
It's a great little walk through into building an OD pedal, and although i haven't finished mine yet, the process of thinking about what all the different components do has been very interesting and educational.

http://www.diystompboxes.com/sboxforum/viewtopic.php?t=17321&highlight=challenge//give%20it%20a%20read%20over%20and%20if%20you%20get%20something%20done%20drop%20a%20schematic%20or%20some%20sound%20clips%20by.have%20fun%20building!trent

[brett]

Hi.  I've only drawn up a few schematics, so I don't know the finer points.  But usually I'd supply power from a line at the top and put an earth (or -ve supply) line at the bottom.  Also, work from an input on the left to an output on the right.  Also, leave some free space.  Like in music, you need some open spaces to prevent sensory overload.

cheers

[Gringo]

Also, take a look at this:

http://www.generalguitargadgets.com/richardo/distortion/

Good luck!

[Jay Doyle]

Due to prodding by Aron and JD (which I thank them for, I think it will be pretty good), I am in the process of writing up a detailed tutorial based on that "challenge" post.

It will probably be at least another two weeks or so until I finish the text and then I have to put it in a respectable format. As I write I think of more and more stuff that can or should be included.

It will be at GGG when I am done and I will post here as well.

Stay Tuned.

Jay

[breakitdown]

I guess a better question would be, where do you start with cap and resistor values?

[breakitdown]

I think maybe I'm jumping way ahead of myself for a few reasons. I dont understand anything about transistor biasing nor do I know anything about opamps or fets and jfets. The links you guys provided were great explanations but still a little too advanced for me. I need to learn the basics about how those kind of things work, I dont think I could just jump in and start toying with opamps and jfets when I have no clue how they work. I read a post on opamps but it too was far more advanced than I am (2 college level electronic courses didnt teach me nearly what I thought it did) Anyone point me towards a more "generealized" post for noobies?

Matt - trying to get all this info to sink in...

[niftydog]

Well, put it this way.  I've studied around 15 hours a week for the last four years to get to where I am... and I'm still learning several new things a day!  I expect to learn stuff about electronics for the rest of my life.

So a simple question like "where do you start..." has many, many, many answers depending on where you want to get too!

Start googling around and you'll get some great info.  the site http://tpub.com/ isn't a bad place to start.  There's heaps of sites offering electronics tutorials from bare bones basic right through to impossibly difficult.

In your case, looking at overdrive you'll want to start learning about transistor amplifiers, op amps, filters, rectification, buffers etc etc.

Perhaps a good place to start would be to learn the very basic uses of resitors and capacitors.  For instance capacitors themselves block DC, but transfer AC signals.  This basic concept is the basis of many types of filters and other circuits.

Google "RC time constant" and "RC filter" to learn some basic concepts.

I warn you though, once you start, you may never stop!

[petemoore]

I guess some of these books are readable ... I seem to have troubles with them ... Got a little here and there, should probably try it again soon.
 Mostly I just go by what I see around here and put the puzzle together.
 One good thing to do is have different printouts around for reference at the same time...like say if you're building a Mosfet Item, that's a good time to study mosfet biasing, having the GEO article about that right there next to the circuit and the schematic can give you multiple reference points from which to draw in the details...taking your own notes is also quite helpful, write down readings you're getting in a circuit before and after altering parts of it and you'll soon get the cause/effect of say changing a biasing resistor etc.  
 Just using your ears and probing around with a DMM in a circuit while you mod debug and tweek it can reveal alot of into.
 GEO has the Rangemaster Article, a very in depth article, great reads in that one, The 'Technology of' articles are quite good, the Rangemaster and Fuzz Face articles and builds are great choices for learning many fundamental things about circuit behaviour.

[breakitdown]

ok I just read a good article at ggg that helped a lot... Thanks for your input guys when I build my overdrive I'll let you guys know how it worked out  

Matt

[Chico]

I suggest biting off very small pieces and hammering away at them until you get it, then move on.  For a newbie (I am too) to say op-amp, jfet, transistor biasing etc. in the same breath is way to much territory to try to tackle at once.

You may want to consider geting a book like Electronic Projects For Musicians by Craig Anderton.  It has easy projects and good basic level explanations of how the circuits work.  (That said, some of his opamp choices are hard to come by, but GGG has circuit board layouts that are redrawn for more readily available components.) Also, the theory in the book is still sound.

After reading the book (or something similar), pick a circuit that you want to build and work completely through it until you are satisfied that you understand it.  Then move on.  You will be amazed how the information you pick up is accumulative.

[gez]

Go along to your local library.  Look through the Electronics section.  Pick something that describes the basics (how trannies work etc).

Within a short time you'll get the gist (there's always this place to ask questions if you don't) then you can start designing your own simple boosters etc.  That's how it worked (works) for me.  

Forget 'War and Peace', there's nothing like a good dry textbook to see you trough the winter...spring...summer...er, autumn...

Knowledge is power.

[puretube]

just saw these linx in another thread:

http://www.allaboutcircuits.com/
http://www.ibiblio.org/obp/electricCircuits/