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Aug 30, 2023

Retro Gadgets: The 1974 Breadboard Project

It is hard to imagine experimenting with electronics without the ubiquitous solderless breadboard. We are sure you have a few within arm’s reach. The little plastic wonders make it easy to throw together a circuit, try it, and then tear it down again. But, surprisingly, breadboards of that type haven’t always been around, and — for a while — they were also an expensive item. Maybe that’s what motivated [R. G. Cooper] to build Slip-n-Clip — his system for quickly building circuits that he published in a 1974 edition of the magazine Elementary Electronics.

The system isn’t really what you would think of as a breadboard today, but it was effective and certainly cheap to build. The biggest problem? It wasn’t something you’d use with DIP ICs. But in the early 1970s, you might not be building very much with ICs, and the ones you used might be in oddball transistor-like packages. Things were strange in the 70s!

In the very old days, people built radios and such on wooden substrates that were actually bread-cutting boards. That’s where the name came from. It was common to draw a diagram with the physical layout you had in mind, glue it to the board, and use it as a guide for building and troubleshooting. Wood was easy to drill and cut. A nail or a thumbtack would make dandy terminals. Probably the last time we saw that done was about a dozen years ago in Make Magazine. Even then, it was only a novelty — few people still build circuits like this, but you can see how [Colin] did it in the video below.

If you had students building circuits, this could be a real drag. So, unsurprisingly, [Orville Thompson] from DeVry Technical Institute got a patent in 1960 for a spring-loaded solderless breadboard. Innovative, but not quite how we know them today.

[Thompson’s] breadboard was more like a spring-loaded patch panel. This would be useful for things you might build on a real breadboard, but in a decade or two, ICs in DIP packages would become a big thing.

In 1971, [Ronald Portugal], working for E&L Instruments, figured out that there would be a market for a board with spring contacts that could accept DIP chips. The patent shows something you’d easily recognize today. AP Products claimed they’d been making solderless breadboards since 1968, but we imagine they looked a lot different.

Of course, breadboards weren’t a common fixture in hobby labs in 1971. By 1977, though, they were small breadboards in the Radio Shack catalog for $9.95 — about half the cost of lava lamp and worth about $50 in today’s money. In 1976, a 6×7 inch breadboard from AP was about $50.

Meanwhile, back in 1974, [Cooper] wanted to put together circuits easily. His solution? A wooden board, some copper pipe, rubber bands, and paper clips. The plan was simple. Drill holes in a piece of plywood to form a grid. The holes were just big enough to pass one-inch pieces of copper pipe through them. Epoxy would hold the pipes in permanently.

That leaves the springs. A piece of scrap wood and some nails make a jig for bending paper clips into hooks that grab the lip of the copper pipe. They also grab rubber bands, so there are two hooks in two different pipes attached to each rubber band. When you pull up on one hook, the other hook pulls back against you. Slip your wire or component under the hook, and the rubber band tension will hold it in place.

Some simple labels finish up the board. Not a bad project, and for some circuits, it may be even better than a conventional solderless breadboard. Of course, not DIP IC friendly at all.

We can see how this would have been an economical solution. You probably had scrap wood, paper clips, and rubber bands hanging around. Copper pipe is common enough, too. By contrast, a 1976 Heathkit catalog touted the new Heathkit ET-3300 breadboard. Four breadboards were mounted in a case with a triple-fixed (+5, +12, and -12) power supply. While $80 doesn’t sound like that much, that was a third of the median US weekly salary in 1976. You also saw a lot of breadboards in cases with things like LEDs, switches, and other external components, but they were not cheap, either. You can see [Lee Adamson] repairing an ET-3300 in the video below.

So we can see what might motivate you to find a piece of scrap wood and stick some pipes in it. Are we suggesting you do the same? Probably not. Although for the right project, it would give a decidedly nostalgic and interesting look. With a little decoration, it would probably look good for a steampunk build, for example.

E&L Instruments literally invented the modern breadboard, but you don’t really think of their name as synonymous with the product. Maybe because they cost $1,300 back then. You can see [CuriousMarc] tear down one he calls an “eBay Disaster” in the video below.

The Slip-n-Clip was never very famous, we imagine. But it was a great example of how ingenious people were when they couldn’t just order cheap stuff from the comfort of their couch. We wonder if anyone reading this actually built one back in the day. Let us know in the comments.

Everyone “knows” that solderless breadboard have a lot of extra capacitance and other bad circuit parameters. But how bad is it, really? We’ve seen them subject to all kinds of surgery and even downright torture.

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