How Printed Circuit Boards are Designed (1960 Edition)

We found this gem in A Manual of Engineering Drawing for Students and Draftsmen, 9th Ed., by French & Vierck,1960, p. 487.

Printed Circuits allow miniaturization and the elimination of circuit errors—advantages that cannot be obtained by other methods. Once a pattern or suitable design is established, preparation of a black and white drawing can start. Scales for reduction, for example, 4 to 1, 3 to 1, or 2 to 1, are used. To insure sufficient bonding area of the metal laminate during soldering operations, lines should not be less than 1/32 inch in width when reduced. Line separation should never be closer than 1/32 inch on the final circuit. Figure 19.24 illustrates the drawing of printed circuits.

PCBmodE: Make your PCB a work of art

The folks at BoldPort have created PCBmodE, free open source software for designing printed circuit boards, but with an artistic perspective. Traditional EDA tools are designed from an engineering perspective, whereas PCBmodE treats the PCB as a creative palette. They aim to give you freedom to express your design with all the tools of the medium.

We wanted to create circuit boards that have curvey traces, meandering paths, and multiple soldermask layers, so we developed PCBmodE (say “PCB mode”), an open source Python software that unshackle us from the constraints imposed by traditional PCB design tools. We use the power of Inkscape – the leading open source vector graphics editor — to achieve any shape imaginable. Together with our powerful back-end tools, we can manufacturable beautifully functional boards.

They’ve posted about several of their example boards including pieceof (pictured above), a Raspberry Pi daughterboard called shimmy, and a tribute board dedicated to Bob Pease. This is a really neat approach to building circuit boards, and it looks like it has a lot of potential.

Version 1.1 of the ’2313 board

2313_topside2
We’ve just revved our open-source ATtiny2313 breakout boards to version 1.1.
There are a couple of nice improvements for the new version. First, we made the board single sided to match our original ATmegaxx8 board– this means that it’s relatively easy to print out the layer separations and make your own at home, if you like to etch your own boards. We also changed around the configuration of the prototyping areas, making it so that you can now fit up to two DIP-8 packages, breadboard style, on the board.
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A single sided circuit board

Mobius Circuit - 21

In electronics, it is common to talk about single sided circuit boards. The most common type is a circuit board that only has printed wiring on one side, and components on the other side. There are also surface-mount boards, where all the wiring and components sit on one side. But aren’t all of those reallyjust two-sided circuit boards where you only put components on one of the sides?

Here we present a method of making your own authentic single-sided circuit board.
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Business card AVR breakout boards: Version 1.1

Card version 1.1

We’ve just released a new version of our super-handy business card sized target board for programming 28-pin AVR microcontrollers like the ATmega168 and ATmega328. These are just the thing for programming these chips through an ISP programmer like the USBtinyISP.

We use these for a lot of our simple microcontroller projects; Tennis For Two and the Lissajous POV come to mind. The new version has basically the same design but adds some extra prototyping area and makes the holes big enough to accept a ZIF socket:

ZIF Kit
Like the original version of this target board, this circuit board is a fully open source hardware design. For much more information– including the detailed design files– please see the update that we’ve added to the end of our original article about this project.

Laughing Squid logo PCB

Laughing Squid Logo PCB

It seemed to us that the Laughing Squid logo was just crying out to be recreated as a real printed circuit board… so we made this one and gave it to Scott (Laughing Squid’s Primary Tentacle) at the Maker Faire earlier this month. He was a even good enough sport to let us play with his logo without telling him what we were using it for– so we were able to keep it a surprise!

The circuit board is a 3.5″ square. It would make a good coaster with rubber feet added to the bottom, once we get the contrast turned up a bit– the background was supposed to be considerably darker. If enough people are interested, we could make up a batch of these to put in the Squid Store, so let us know!

(Photo CC by Scott Beale / Laughing Squid.)

Laying out printed circuit boards with open-source tools

There has historically been, and still is, a lack of good, free MacOS native EDA (electronic design automation) software. The situation has somewhat improved in the past few years because the X11 layer in Mac OS X allows graphical unix applications to run natively on the Mac, concurrently with other programs. I recently learned to use some of these tools in the gEDA suite to lay out printed circuit boards. These (loosely, if at all, organized) notes should be helpful to anyone that wants to get started making PCBs using a mac, linux, or other unix-like system.
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