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General convetions in documenting my projects There are a few simple rules to make life easy, but if they are not known, or ignored they can make life quite miserable. Some project files are present in Acrobat PDF form. It is a very popular document format used for presenting electronics datasheets, application notes and various other documents. You will need Acrobat Reader to see these documents, which can be downloaded freely from Adobe's site : PDF document page size usually is A4, but it can be A3, A2 (or similar) as the size of the contents may require it. It is very important for printing PCB drawings that you print them with "Fit to page" option UNCHECKED. Otherwise, the rescaling tht the printer driver does will distort the PCB drawing, the pin distances being extremly important ( while you can still fit a resistor if the hole goes 0.5mm in one direction, I'd like to see you do that with the pins of an IC...) Viewing PCB drawings and transfering them to a PCB : The most used layers when creating a PCB layout are TOP, BOTTOM, COMPONENT SIDE SILK, DRILL MASK. Others, less frequently used : solder side silk, resist mask, SMT mask. There can be more layers for traces, but more then 2 are used only in industrial manufacturing. As a general rule, a PCB is viewed from abovewith the component side, the side where the components are placed, towards the viewer TOP, sometimes referred to as C1, is the top layer with copper traces. Viewed from above, this is always presented as is. BOTTOM, sometimes referred to as C10, is the bottom layer with copper traces. The editor I'm using uses top view at all times. Exporting the bottom layer requires that I mirror it so it can be used for transfering it on the copper, so : When presented standalone, BOTTOM is viewed from bottom upwards. It is the mirror view (horizontally flipped) of the top view. Keep this in mind if you are puzzled why the holes appear not to be in the same place for each layer. When presented in a multicoloured combo with all layers, the BOTTOM layer is presented as viewed from above. (though this setup will be rare) COMPONENT SIDE SILK, sometimes referred to as CSLK, is the drawing that is painted on the component side of the PCB to indicate component placement. It is viewed from above and in general will not be drawn on the PCB (factory usually does), only used as a separate guide for component placement. DRILL MASK, sometimes referred to as DRILL, is the layout for drilling the holes in the board for component pins, mouting screws, etc. It is viewed from bottom upwards, same as layer BOTTOM. SOLDER SIDE SILK, sometimes referred to SSLK, is the drawing that is painted on the solder side of the PCB to indicate component placement, when applicable (usually some SMD components). It is viewed from the bottom upwards (like layer BOTTOM) and in general will not be drawn on the PCB (factory usually does), only used as a separate guide for component placement. Will be presented only when there are components placed on the solder side. RESIST MASK is rarely used by the average amateur. It is a protective paint that is placed on the board, with only the pads left uncoated so solder can adhere. Since the manufacture requirements for this is not easily at the disposal of the average amateur circuit builder, I don't present these. RESIST MASK usually is drawn for TOP and BOTTOM layer, viewed accordingly (layer facing the viewer). SMT MASK is related to Surface Mounted Technology - components mouted directly on the surface of the board, including pin soldering. Since I used SMT very rarely, I stil haven't figured this out, so it's meaning will be described in a later update. Drilling conventions : Since I need not export for a drilling machine in an industrial process, the DRILL MASK will show each pad that has a hole with the pad outline and fill as black and the hole as white in the center. Since hole sizes can be difficult to figure out, here's a table with the most used hole diameters and when they are used : Hole diameter Usage 0.8mm IC pins, most small packaged resistors and capacitors, low power diodes, low power transistors (TO92, TO18, etc packages) 1mm Medium power diodes, some carbon resistors rated above 1W, large electrolythic capacitors, small connectors, jumpers, wires up to 0.8mm diam. 1.5mm adjustable capacitors (trimmer), adjustable resistors (trimpot), TO220 packaged (and similar) transistors, IC's 3mm M3 mounting screws For other more exotic componets like coils, transformers, other large packages, wires soldered to the board, higher power devices, shielding, etc, check the lead diameter and drill a hole slightly larger then that value. Some limitations : The schematics and PCB design software I am using has some limitations, that text associated with components cannot be moved independantly. Consequently, sometimes in a schematic or CSLK or SSLK component names and/or values may partially overlap. While in some cases I manage to correct this in the files that I post, this may not always be the case. You'll have to try and figure out which is which. For some projects that use high density traces and placement on both sides of the PCB, I may present an aggregate view with all layers stacked, each having an amount of transparency and a different color. However, it's up to you to solve the overlapings.