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This mighty machine sparked a revolution in our use of media. It’s a Sony Betamax video cassette recorder from 1979. This monster weighs about 36 pounds. The engineer in me find it fascinating: there is nothing digital, it’s a truly analog machine -- all moving pieces and parts.

Early adopters of the Betamax used it to record television shows -- a revolutionary concept at the time -- because prior to the Betamax you had to watch a show when it was broadcast. It threaten the entertainment industry so much that in 1979 they argued that recording television shows at home infringed on their copyright. It all came to a head in a Supreme Court case -- Sony Corporation of America versus Universal City Studios -- where five justices allowed home recording. Although Sony won this court battle, they ultimately lost out to a machine that used this size tape. This is a VHS recorder made by Sony’s great rival JVC.

Both machines solved the same problem: How to store information compactly on a tape. Here’s the brilliant innovation used by both machines. The machine grabs the tape, drags it forward, as this silver drum starts to spin rapidly. The drum has two electromagnets (called heads) arranged on opposite sides of the drum that read the magnetic information on the tape. That rotating head allowed for a compact recorder: in many previous recorders the magnetic heads didn’t move, only the tape. Because there was a limit to how fast the tape could move, it took a lot of tape -- about a seven inch reel to record an hour, which means that a movie would need two 7-inch reels inside a cassette. So, the rotating heads dramatically reduced the amount of tape needed, reducing the size to where it could be easily held in a cassette.

So, if the machines are so similar why did Betamax lose to JVC? Many thought the betamax machine would win: It had the better image quality and the Betamax is decidedly better built. Compare ejecting a tape on the Betamax to the VHS. First, watch the Betamax. Note how smooth it is. And then watch the VHS. That’s abrupt and will wear out the mechanism. Yet, to my engineer’s eye the VHS was the better solution.

First, the VHS was lighter than the Betamax: 29 and a half lbs compared to 36 lbs for the this Betamax machine. That’s a huge difference for a mass manufactured object. It impacts everything from material costs to assembly time to shipping costs. So, at the low end of the market the VHS machines were cheaper than Sony’s Betamax.

Second, the earliest Betamax tapes played for only one hour, VHS played for 2 hours -- enough time for a movie. The ultimate killer, though, was the rental market.

While, Betamax focused in its ads and energies on time shifting -- their ads featured headlines like “Watch whatever, whenever” -- while JVC, the maker of the VHS system, created relationships with the nascent video rental industry. When this market grew, VHS dominated in titles. While you could for a while find both formats eventually retailers began giving shelf space to the slightly more dominant brand, which then dominated even more.

So, the Betamax versus VHS dispels the notion that simply being first to market is the most important issue. It reminds us that technical excellence in one area isn’t enough -- here the superior picture quality of Betamax -- but that all technical aspects matter. For any mass manufactured object, the winner is usually the one that is just good enough. I’m Bill Hammack, the EngineerGuy.

Stories of Tech Failure

When we look at the failure of technological objects in the marketplace we tend to be very pat and trace failure to a single cause. Yet technological things fail in the marketplace for many reason. So, in this series Bill takes a deeper look at the failure of three famous engineered objects: the Picturephone; the Betamax video cassette recorder, and the Dvorak keyboard.

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