freestompboxes.org

hey guys

does anyone know of any online tutorials for tracing pcb's?

i was going to draw one up on how i do it.

ie, photograph both sides of the board, flip and allign in photoshop, number parts, write out the nets, reconstruct to schem form..

but i dont want to waste my time if there already is one out there..

i might learn something new also

cheers
kt

Do it! I think it would be great and I've never seen anything like it before...

briggs wrote:Do it! I think it would be great and I've never seen anything like it before...

+1!
I've never seen or heard of anything quite like that before.

The way I've done it is to scan the top side and trace side of a board (or use good quality, same sized photos) and then print both on clear projection paper. Then when you "mate" the component side and trace side printouts, you can easily see where the traces go.

Doing anything else is just doing too much work !

briggs wrote:Do it! I think it would be great and I've never seen anything like it before...

+2 The more info out there, the better

Rule nr. 1: Check at Geofex first!

http://www.geofex.com/Article_Folders/howtrace.htm

Suggestion #1: Oscar likes pictures, otherwise ADHD takes over and then its over.

Mayniac wrote:Rule nr. 1: Check at Geofex first!

http://www.geofex.com/Article_Folders/howtrace.htm

You beat me to it!

Mayniac wrote:Rule nr. 1: Check at Geofex first!

http://www.geofex.com/Article_Folders/howtrace.htm

Condensed version, as mentioned earlier in thread....

The way I've done it is to scan the top side and trace side of a board (or use good quality, same sized photos) and then print both on clear projection paper. Then when you "mate" the component side and trace side printouts, you can easily see where the traces go.

Doing anything else is just doing too much work !

Resize & layer the images in (eg) Photoshop. Then with the top layer as the component side you can turn the layer on & off to do the tracing.

Torchy wrote:Resize & layer the images in (eg) Photoshop. Then with the top layer as the component side you can turn the layer on & off to do the tracing.

This is also one of my favourite ways.
Usually, I start with the supply lines including Vref,..etc. IMHO it really helps to mark them with different colours on a print out because when you later on start tracing e.g. from the input you immediately see when a trace goes to e.g. Vref.
Also speeds up chip identification in case the labelling was removed.

Markus

When i started doin the woolly mammoth i photographed both sides, put both thru "the gimp" (free photoshop thing) so the components where on the trace and thats about it.

key is,same sized pics hey....which i didnt have.

I never finished it cause i found a schem online and it was my first experience with double sided PCB's which was doin my head in to be honest.

I've found that scanning both sides and using photo software is good, but there's a better one.

I use the Corel Draw package, which includes Corel Photopaint to do the sizing/stretching to square, and so on. But then importing that into Corel Draw lets you put the top on one layer, the bottom on another layer, and use yet a third and fourth layers for drawing in first the pads, then the copper traces. CD lets you make layers invisible at a click, so you can turn off the top side and get the pads and traces right on the bottom, then turn off the bottom and traces, and fill in the top side.

It's even better if you think like a PCB layout guy.

In your draw program (or on your matte-surface mylar overlays if you're old-school) assign one layer to component bodies, one to pads, one to top side traces, and one to bottom side traces. Use two more for top and bottom scans. Work ENTIRELY from views that are from the top/component side of the board so you don't confuse yourself.

Make all the layers invisible except the bottom scan. The bottom should be mirrored so it views as though you're looking through the PCB. Stack the pads layer on top of the bottom-view layer, and put in color-filled circles for every pad. In through-hole boards, the pads will be on the top side as well.

When that's done, put the bottom traces layer on top of the pads layer and the bottom scan, and put in wide colored lines for the traces.

When that's done, click the bottom scan and bottom traces layer to invisible. Make the top layer visible below the pads layer. Now trace in all the traces you can see. Add to it all the traces that you can see by referring to the PCB with a magnifier or loupe. Then get out your ohmmeter and use needle-probes to trace out the remaining traces where they go under parts.

This is usually easy enough to do with through-hole stuff. If there is a via under the part, you'll already know it from the pads layer tracing. If you're careful, you can get all of it, or close enough to guess the rest.

Now all you need is a component layer. Turn off the pads and traces, leave the top side scan on and draw in component outlines.

When you get done, what you have left is the PCB layout. It can probably be manipulated to work as is for toner transfer, depending on how fussy you were with getting the photos the correct size and squashed-ness. Drawing the schematic is then pretty trivial.

But it's simple to use the layers you've traced as a guide and go into a layout program and place parts, then run traces on grid. The result is very suitable for etching.

It helps to understand the PCB layout frame of mind in tracing. I'm not tossing this in here for spam purposes because I sell a trunkload of them anyway, but if you want a quick guide to the PCB frame of mind, get a copy of my PCB Layout for Musical Effects book from Small Bear. It will not only teach you to do pro-quality layouts, but also improve your tracing by getting your mind right.

Thanks RG
I like using Corel Draw too - you can define any shape or size of pad, or track width with ease, and it is also great for designing or cloning front panel labels etc.
Thanks for sharing the layer info - I must practice using this function
Cheers
bajaman

A BIG Thank You R.G.
I do reccommend R.G.'s book to anyone doing layouts.
There are some things addressed in the book that can help just about everyone.

For those good at tracing circuits. I have never traced a circuit. But I was curious. How hard is it to do? I notice all the goop people use to prevent the ability to trace. Can you trace a circuit without seeing the trace side? Can you do it with just the components? Can you trace a pedal that has a gooped up trace side?

Try the sticky at the top of the page. You need to see the traces, yes. It is just a matter of being methodical. If the pedal designer is smart ( ), they will have left some traps, such a single thread of copper wire which comes off with the goop, conductive paint, etc.

If the pedal designer is smart ( ), they will have left some traps, such a single thread of copper wire which comes off with the goop, conductive paint, etc.

Oh no - what an arsehole thing to do
bajaman

thanks frank i missed it all. what do u mean traps? what would the copper and conductive paint do?

It is a bit like building a Pyramid. Goop will slow down the determined attacker, like a fence would, but not for long. So you might want to have some components damaged so they don't work in a fake section of the circuit that really does nothing, hollow out an IC from underneath and hide some SMD components there, use your imagination. I expect somebody sells components with fake identification. You can have a conductor which comes off with the gunk, such as silver paint, or a very thin strand of wire. The conductor might be part of the circuit, it might not be. You can have a lot of fun here if you are paranoid about your $400 tube screamer clone.
R.G. Keen started a thread about this once. Falsifying PCB traces is my favourite idea.