Old Circuit Boards Are Weirdly Pretty: Cold Start

We all know our cars are jam-packed full of little parts, things that connect moving things or bits that hold in fluids or spinning shafts or bits of metal designed to let electrons flow through them in controllable ways. We don’t always look at these parts for their aesthetic qualities, but sometimes you can’t help but notice. And today, for whatever reason, I noticed the strange visual appeal of a part that we generally don’t think of as visually all that interesting: the circuit boards of an ECU.

Specifically, I was looking at one of the first ECUs ever to be used in a production car, the Bosch D-Jetronic fuel injection system, which was really an update of the old 1950s-era Bendix Electrojector system. The first production car to use this system was the Volkswagen Type 3, and it was in an old brochure for the Type 3 that I saw this ECU board.

Here’s the picture from the brochure:

Let’s zoom and enhance on the circuit board, and what the hell, add a little blue tint:

What strikes me most about this circuit board compared to the more modern boards I see is the seeming chaos of it all. It’s of course designed rationally and to a very specific circuit diagram, but it just looks so haphazard compared to modern boards. There’s no true digital circuits on that ECU there, and about 25 transistors are doing most of the processing.

VW was quite proud of their computer-in-a-car and featured it in ads:

The “think” sign references the old IBM slogan, which was also “think.”

Here’s a period video with some great close-ups of the PCB and its components:

Here, look at a close up of a more modern ECU, this one from a Scion:

Of course, the components are far smaller and the density of the traces is vastly greater, but there’s also a much more rigorous grid-type organization system going on here. There’s orders of magnitudes more transistors and other components on here, now surface-mounted, and the whole thing looks like some kind of advanced alien metropolis seen from far above as opposed to the scattershot-looking complexity of the old board.

What I really like about printed circuit boards from the ’60s and ’70s though are the traces themselves, which often have a strange psychedelic-art kind of look. Here’s an example of what I mean from a very famous source, the now iconic Atari CX40 joystick:

See those strangely flowing and almost biomorphic shapes of the traces? That kind of thing was all over ’70s printed circuit boards, including some found in cars. Here’s the back of another Bosch Jetronic ECU board from the ’70s, with plenty of whimiscal-looking traces:

…or the snakey, labyrinthine goodness of this Mopar ECU from some Chrysler:

Anyway, next time you’re at a junkyard, I highly encourage you to look for something from the mid 70s or 80s, dig around and find some ECU box bolted under a seat or to a firewall and pry it open to get to the hidden beauty within. There’s so many more and better examples out there. They make fun wall art!