Drawing Schematics

[tech2014]

Hi everyone. As repair techs, we all know how hard it is to find schematics for TV boards. What I would like to know is if anyone here draws there own schematics. If so, what program do you use and what process do you go through.

Any advice would be greatly appreciated?

[dick_barton]

Re: Drawing Schematics

Design Spark was free but I don't know if it is anymore

http://www.rs-online.com/designspark...-pcb-home-page

[Alastair E]

Re: Drawing Schematics

For reverse-engineering small sections of complicated boards--pencil and paper cant be beaten.
--pointless messing with pc's and mouses for this sort of work--too messy and time-consuming.

[stj]

Re: Drawing Schematics

i draw lots of schem's, using EagleCAD.
http://www.cadsoftusa.com/
it's free for small pcb's and there is no limit to schematic size.on the free version!

other people like to use KiCad
http://kicad-pcb.org/
totally free - i need to try it soon.

both work on Lin,win & mac

i found this btw.
http://www.bigmessowires.com/2010/05/03/eagle-vs-kicad/
it may interest you.

[keeney123]

Re: Drawing Schematics

If the board is multi-layer it would be difficult to reverse engineering the schematic. I think on single layer boards it would be best to use the virtual board layout like what BudM uses. Then follow it up with the actual board and ohm meter to verify the points are connected. You would print out a picture of the virtual board layout and use a red marker to check off the lines to each node. At the same time you can start drawing the schematic. So you would red check the node points after you verify it with a meter. So if you go from node point 1 to node point 2. You measure that continuity to verify, you then draw that line and then you check that line off from node 1 to node 2. You then proceed to the next line. The only other way that I know of instead of using a virtual is to keep on ohming out from bottom to top flipping back an forth starting at one node following all the lines at that one node, both top and bottom side of the board and drawing them down on a piece of paper. Then you would go to the next node and do the same thing. I would put a sticker on that node after I was done with it. I would also arbitrarily label each component so you know which one you are working with unless the manufacturer has labeled them and therefore you can use his labels.