Spy Tech: The NRO And Apollo 11

September 25, 2025 by Al Williams 13 Comments

When you think of “secret” agencies, you probably think of the CIA, the NSA, the KGB, or MI-5. But the real secret agencies are the ones you hardly ever hear of. One of those is the National Reconnaissance Office (NRO). Formed in 1960, the agency was totally secret until the early 1970s.

If you have heard of the NRO, you probably know they manage spy satellites and other resources that get shared among intelligence agencies. But did you know they played a major, but secret, part in the Apollo 11 recovery? Don’t forget, it was 1969, and the general public didn’t know anything about the shadowy agency.

Secret Hawaii

Captain Hank Brandli was an Air Force meteorologist assigned to the NRO in Hawaii. His job was to support the Air Force’s “Star Catchers.” That was the Air Force group tasked with catching film buckets dropped from the super-secret Corona spy satellites. The satellites had to drop film only when there was good weather.

In the 1960s, civilian weather forecasting was not as good as it is now. But Brandli had access to data from the NRO’s Defense Meteorological Satellite Program (DMSP), then known simply as “417”. The high-tech data let him estimate the weather accurately over the drop zones for five days, much better than any contemporary civilian meteorologist could do.

When Apollo 11 headed home, Captain Brandli ran the numbers and found there would be a major tropical storm over the drop zone, located at 10.6° north by 172.5° west, about halfway between Howland Island and Johnston Atoll, on July 24th. The storm was likely to be a “screaming eagle” storm rising to 50,000 feet over the ocean.

In the movies, of course, spaceships are tough and can land in bad weather. In real life, the high winds could rip the parachutes from the capsule, and the impact would probably have killed the crew.

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Build Your Own 6K Camera

September 23, 2025 by Al Williams 17 Comments

[Curious Scientist] has been working with some image sensors. The latest project around it is a 6K camera. Of course, the sensor gives you a lot of it, but it also requires some off-the-shelf parts and, of course, some 3D printed components.

An off-the-shelf part of a case provides a reliable C mount. There’s also an IR filter in a 3D-printed bracket.

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First Transistor Computer Reborn

September 21, 2025 by Al Williams 15 Comments

Ok, we’ll admit it. If you asked us what the first transistorized computer was, we would have guessed it was the TC from the University of Manchester. After all, Dr. Wilkes and company were at the forefront and had built Baby and EDSAC, which, of course, didn’t use transistors. To be clear, we would have been guessing, but what we didn’t know at all was that the TC, with its magnetic drums and transistors in 1955, had a second life as a commercial product from Metropolitan-Vickers, called the Metrovick 950. [Nina Kalinina] has a simulator inspired by the old machine.

The code is in Python, and you can find several programs to run on the faux machine, including the venerable lunar lander. If you haven’t heard of the Metrovick, don’t feel bad. Oral histories say that only six or seven were ever built, and they were used internally within the company.

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A Serial Mouse For A Homebrew 8-bit Computer

September 21, 2025 by Al Williams 2 Comments

[Too Many Wires] has a custom computer he’s building. He wanted a mouse, but USB is a bit of a stretch for the fledgling computer. We might have opted for PS/2, but he went for something even older: a serial mouse connected with a DE-9 (colloquially, a DB-9). Check it out in his recent video update on the project below.

Don’t remember serial mice? They were very common many years ago, and apparently, you can still buy new ones, which makes you wonder what people are doing with them. If you are an old hand at serial, you’ll immediately know why he couldn’t get it to work at first. If you haven’t worked with RS-232 gear before, you’ll learn a lot.

The protocol is simple enough, and you can read the code or find plenty of old documents. He’s using a UART chip, which offloads the CPU. However, the PS/2 mice are very easy to work with directly, and you could skip the +/- 12V RS-232 and other issues.

Either way, however, using an RS-232 or PS/2 mouse in a project is relatively straightforward. You might not think you need a mouse, but don’t forget, they are really accurate two-axis sensors. An optical mouse on a motion table, for example, could be worth something.

The computer is based on [Ben Eater]’s design, if you want more details on that. Can’t decide between RS-232 and PS/2? You don’t have to.

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For A Robot Claw, The Eyes Have It

September 21, 2025 by Al Williams 3 Comments

Have you ever wished your hand had an extra feature? Like, maybe, a second thumb? A scope probe pinky maybe? Well, if you are building a robot effector, you get to pick what extra features it has. [Gokux] has the aptly named Cam Claw, which is a 3D printed claw with a built-in camera so you can see exactly what it is doing.

The brains are an ESP32-S3 and the eyes — well, the eye technically — uses an OV3660 camera. There’s even a light in case you are in a dark space. A servo drives it, and the printed gear train is pretty fun to watch, as you can see in the video below.

This project is all about the mechanics. The electronic hardware is trivial. A battery, a power controller, and a servo complement the ESP32 and camera. Six LEDs for light, and the job is done.

Obviously, the gripping power will only be as good as the servo. However, we really liked the idea of putting eyes on a robot hand where they count. Of course, the claw you really want a camera on is in the arcade. We’d like to see cameras on some other robot appendages.

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Regretfully: $3,000 Worth Of Raspberry Pi Boards

September 20, 2025 by Al Williams 53 Comments

We feel for [Jeff Geerling]. He spent a lot of effort building an AI cluster out of Raspberry PI boards and $3,000 later, he’s a bit regretful. As you can see in the video below, it is a neat build. As Jeff points out, it is relatively low power and dense. But dollar for dollar, it isn’t much of a supercomputer.

Of course, the most obvious thing is that there’s plenty of CPU, but no GPU. We can sympathize, too, with the fact that he had to strip it down twice and rebuild it for a total of three rebuilds. One time, he decided to homogenize the SSDs for each board. The second time was to affix the heatsinks. It is always something.

With ten “blades” — otherwise known as compute modules — the plucky little computer turned in about 325 gigaflops on tests. That sounds pretty good, but a Framework Desktop x4 manages 1,180 gigaflops. What’s more is that the Framework turned out cheaper per gigaflop, too. Each dollar bought about 110 megaflops for the Pis, but about 140 for the Framework.

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Forgotten Internet: The Story Of Email

September 17, 2025 by Al Williams 25 Comments

It is a common occurrence in old movies: Our hero checks in at a hotel in some exotic locale, and the desk clerk says, “Ah, Mr. Barker, there’s a letter for you.” Or maybe a telegram. Either way, since humans learned to write, they’ve been obsessed with getting their writing in the hands of someone else. Back when we were wondering what people would do if they had a computer in their homes, most of us never guessed it would be: write to each other. Yet that turned out to be the killer app, or, at least, one of them.

What’s interesting about the hotel mail was that you had to plan ahead and know when your recipient would be there. Otherwise, you had to send your note to their home address, and it would have to wait. Telegrams were a little better because they were fast, but you still had to know where to send the message.

Early Days

An ad from the 1970s with a prominent Telex number

In addition to visiting a telegraph office, or post office, to send a note somewhere, commercial users started wanting something better at the early part of the twentieth century. This led to dedicated teletype lines. By 1933, though, a network of Teletype machines — Telex — arose. Before the Internet, it was very common for a company to advertise its Telex number — or TWX number, a competing network from the phone company and, later, Western Union — if they dealt with business accounts.

Fax machines came later, and the hardware was cheap enough that the average person was slightly more likely to have a fax machine or the use of one than a Telex.

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