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Schematic To PCB

Started by MmmPedals, November 28, 2009, 11:13:41 PM

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MmmPedals

I have a schematic of a very rare pedal (on loan on condition not to post). I want to lay it out for a pcb. I dont trust myself to lay it out alone because i am new at reading schematics and dread that "one stupid mistake". I tried Eagle and lets just say its a good thing i dont own a gun. The libraries make impossible to find anything. Any suggestions?

Ripthorn

If this is the same pedal you asked about the transistor, then I will go edit my post there.  In the mean time, the only way to get good at layouts is to do them over and over.  I would get the gaussmarkov library as it is geared towards pedal builders and that will greatly simplify finding things in there.  Other than that, good old time and work is what you need.
Exact science is not an exact science - Nikola Tesla in The Prestige
https://scientificguitarist.wixsite.com/home

newperson

what is the pedal?  odds are that there is one already made.

R.G.

Quote from: MmmPedals on November 28, 2009, 11:13:41 PM
... I want to lay it out for a pcb. I dont trust myself to lay it out alone because i am new at reading schematics and dread that "one stupid mistake". I tried Eagle and lets just say its a good thing i dont own a gun. The libraries make impossible to find anything. Any suggestions?
Can't help much with libraries. They are what they are, better or worse.

But for converting schematics to PCBs, there is a book you might like to get. It's called "PCB Layout for Musical Effects", and it's sold through Small Bear Electronics. It is a detailed tutorial on taking a schematic and doing the manipulations to the thing to get it on a PCB. I think it's a good intro - but I would, as I wrote it.  :icon_lol:

Oh, on libraries, I actually may have some help. List out the parts you want to use ahead of time. Take the parts list that you will have to produce eventually anyway, and figure out what physical package the parts come in. All the resistors, for instance, will likely be 1/4W carbon film resistors. Go find those in the libraries, no matter how long it takes. That's probably 30% of your parts done in one lookup. Now caps. Film caps can almost always go into a single footprint with holes on 0.2" centers. Look that one up, no matter how long it takes. You're now probably 60% done, maybe more. Now look up the electrolytic caps, always going to a parts supplier on line and finding at least one example of a part you can actually buy. Mouser makes this easier than most places, BTW. Figure out the sizes of the electros, probably only one or two physical sizes, and then go find those in the library - that's right, no matter how long it takes.  :icon_biggrin: The last are probably ICs and transistors. ICs will all be DIP packages, find them in libraries; now the remaining transistors.

Just for you, I'm going to reveal an uber-secret of PCB layout - figure out what the physical size, mounting holes, and any mechanical constraints of your PCB will be before you ever place a single part on the board outline. Yep - the board outline and mounting comes FIRST. If you wait til last, you will be a very unhappy camper. So you have to know what enclosure you'll put it into before you lay out the board. Or at least what the biggest PCB size is that will fit into your chosen enclosure. Some things simply Will Not Work, or will take a lot of skill and experience to make them work. I can generally put all of the traces on a PCB which holds only ICs, transistors, 1/4W resistors and typical caps in very little more space than just the sizes of the parts themselves. But I've been doing this for decades now. Don't make yourself miserable if you can't do it all at once. It's a lot like playing guitar - you have to practice to get better.
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

solderman

DIY layout creator is the answer to your (all) questions ;)
Easy to use, easy to learn and for free. get it and get at it..
The only bad sounding stomp box is an unbuilt stomp box. ;-)
//Take Care and build with passion

www.soldersound.com
xSolderman@soldersound.com (exlude x to mail)

MmmPedals

Thanks for the help. Maybe i will try my own layout. Maybe someone can help me locate the components i need in eagle libraries.
Caps-i found what i think is the correct one but how do i know if it is the correct size?
Resistors- Way too many no idea which one to chose.
Elec. Caps- Searched FOREVER and couldn't find it. Maybe i dont know how to use the library properly.
transistor- probably could locate it usig the pics they give but i was so frustrated by not finding the Elec. caps i gave up
Pots-??? dont want them on the board but should i put them in the schematic?
Thats it for components (no ic's in this one)

ubaid88

#6
In my experience for eagle. Use guassmarkov libraries for eagle. It has a great collection of components commonly used in stompboxes. You can download them from here.
http://gaussmarkov.net/eagle/lbr/gm-lbr.zip

Also on his site on you find an very easy guide to use eagle for beginner, from drawing schematic to final pcb layout.

http://gaussmarkov.net/wordpress/tools/software/eagle-cad/

I have experience with many softwares like ki-cad, diptrace, pcbwizard, express pcb and multisim but eagle is the best. Just like you i didnt liked eagle at first but when you get use to it. It is a piece of cake.

caspercody

I just started using Eagle for my first layout. And yes must use Gaussmarkov layout, and also use the hobby.dru settings. This is a  pre set file that changes all the pads to a proper size.

cpm

i've been using eagle for 1 week (first time with a cad program), and haven't come into any problem drawing schematics, looking for parts, etc. I am using GM libs mainly for pots, but i could create my own parts easily, like a LDR, a 3-part 4053, etc...

come on, its not that hard...

caspercody

It is not that hard to do the schematic. But, for me, the pcb portion is a little more time consuming and not as easy as the schematic. The one pcb layout I have done has like six jumpers, andabout twice the size as the ones done by others.

bobp1339

You are correct... A layout is harder and more time consuming to do than a schematic. However, that's the way it is. 

I find it's a bit like a game... Put all of the pieces on the size of the board that you need and figure out how to connect them in the correct way.

Have fun with it!
"I love the smell of solder in the morning..."

...Bazz Fuss, EA Trem, Ross Comp, MXR Env Filter, Orange Squeezer, custom bass preamp...
http://chindigband.com

solderman

Hi
Yes I agree. It is a challenge you have to like to take on if you want to do your own layouts. To make a design is like chess, you always have to be a couple of move ahead or you are smoked. To make a working layout is no big deal if size and numbers of jumpers do not matter. This is the same challenge I like with the 1590A builds as well. I have used Eagle (GS: site is a gold mine for Eagel) and another share ware (can't remember the name something with first or 1) but I still find DIY the easiest to use. Its raw it's unforgiving, it has no layer and it's all manual. Yes but it is easy and you can keep the focus on planning the layout. But now I have a bunch of people that hassles me all the time to built them the "Small Talk" (after a friend asked me to demo it at a rehearsal studio, BIG mistake) and I don't want to etch the PCB my self (drilling PCB sucks) so now I have to do it in a CAD software so I can have the correct output files to have a bunch of them made professionally.
The only bad sounding stomp box is an unbuilt stomp box. ;-)
//Take Care and build with passion

www.soldersound.com
xSolderman@soldersound.com (exlude x to mail)