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Britain’s Oldest Satellite on the Move: a Space Curiosity

12 Noviembre 2024 at 03:00
Photo manipulation of Skynet-1A hovering a planet

Space and mystery always spark our curiosity, so when we stumbled upon the story of Skynet-1A, Britain’s first communication satellite from 1969, we knew it was worth exploring. The BBC recently highlighted its unexpected movement across the sky – you can check out their full coverage here. The idea that this half-century-old hunk of metal mysteriously shifted orbits leaves us with more questions than answers. Who moved Skynet-1A, and why?

Launched just months after the Apollo 11 Moon landing, Skynet-1A stood as a symbol of Cold War innovation, initially placed above East Africa to support British military communications. But unlike the silent drift of inactive satellites heading naturally eastward, Skynet-1A defied orbital norms, popping up halfway across the globe above the Americas. This wasn’t mere chance; someone or something had made it fire its thrusters, likely in the mid-1970s.

Experts like Dr. Stuart Eves and UCL’s Rachel Hill suggest the possibility of control being temporarily transferred to the US, particularly during maintenance periods at the UK’s RAF Oakhanger. Still, the specifics remain buried in lost records and decades-old international collaborations. Skynet-1A’s journey serves as a stark reminder of the persistent challenges in space and the gaps in our historical data.

Looking for more space oddities? Hackaday has some interesting articles on space debris. You can read the original BBC article here.

A Lesson in RF Design Thanks to This Homebrew LNA

5 Noviembre 2024 at 00:00

If you’re planning on working satellites or doing any sort of RF work where the signal lives down in the dirt, you’re going to need a low-noise amplifier. That’s typically not a problem, as the market is littered with dozens of cheap options that can be delivered in a day or two — you just pay your money and get to work. But is there a case to be made for rolling your own LNA?

[Salil, aka Nuclearrambo] thinks so, and he did a nice job showing us how it’s done. The first step, as always, is to define your specs, which for [Salil] were pretty modest: a low noise figure, moderate gain, and good linearity. He also wanted a bandpass filter for the 2-meter amateur radio band and for weather satellite downlinks, and a bias-tee to power the LNA over the coax feedline. The blog post has a detailed discussion of the electrical design, plus some good tips on PCB design for RF applications. We also found the discussion on bias-tee design helpful, especially for anyone who has ever struggled with the idea that RF and DC can get along together on a single piece of coax. Part 2 concentrates on testing the LNA, mostly using hobbyist-grade test gear like the NanoVNA and tiny SA spectrum analyzer. [Salil]’s tests showed the LNA lived up to the design specs and more, making it more than ready to put to work with an RTL-SDR.

Was this more work than buying an LNA? Absolutely, and probably with the same results. But then again, what’s to learn by just getting a pre-built module in the mail?

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