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Cake day: November 14th, 2023

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  • ARPA was military.

    "From 1958 to 1965, ARPA’s emphasis centered on major national issues, including space, ballistic missile defense, and nuclear test detection.[21] During 1960, all of its civilian space programs were transferred to the National Aeronautics and Space Administration (NASA) and the military space programs to the individual services.[22]

    This allowed ARPA to concentrate its efforts on Project Defender (ballistic missile defense), Project Vela (nuclear test detection), and Project Agile (counterinsurgency R&D programs), and to begin work on computer processing, behavioral sciences, and materials sciences. The DEFENDER and AGILE programs formed the foundation of DARPA sensor, surveillance, and directed energy R&D, particularly in the study of radar, infrared sensing, and x-ray/gamma ray detection."

    ARPA was renamed to DARPA in 1972.

    "DARPA supported the evolution of the ARPANET (the first wide-area packet switching network), "

    https://en.wikipedia.org/wiki/DARPA

    There was no Internet in 1972. It was ARPANET which was run by DARPA. The D was added to reaffirm that ARPA was the department of defense, not civilian research.






  • Not op but in my case I’ve seen huge differences between USB cards and high quality cards. 20 years ago I used to use bt878 capture cards. A few years ago I bought a Viewcast Osprey on eBay.

    In particular I use a svhs tape player with built in time base corrector. The reason for svhs is because the hardware supports actual svhs output. Vhs tapes are store with luminous and chroma as separate signals. With regular composite output, that data is mixed into one signal. This causes interference patterns like dot crawl and color fringing.

    The other big advantage over USB dongles is all the ones I’ve seen don’t let you capture the raw data- it’s pre compressed with lossy like mjpeg or mpeg which is another huge quality drop because you’ll usually want to post process the video with avisynth before compressing it to mpeg4.

    My target is for the captured video to look just as good as it originally did on a VHS player on a crt. So the interlaced to progressive conversion is always tricky. I don’t personally do it but one trick to keep resolution is to capture at 60fps and play each 30i field doubled. That way no detail is lost in the source and it uses your eyes to motion blur the fields together.











  • I’ve done it successfully for two Tripplite 1500va and two APC 750va UPS’s. They’ve been running for over 4 years now.

    I bought a lifepo4 that specifically said it had a lead acid drop in replacement BMS (battery management system).

    The only problem I have had was when I had a two day power outage. After running to complete drain ( and they lasted over 2x longer than my older lead acid), the Trupplites wouldn’t charge up after power was restored. I had to pull the batteries and charge them outside the ups to get everything working again.

    Under normal use they have worked great.

    Lifepo4 works fantastic as a drop in because the peak charge of lead acid is only 80% charge of lifepo4. This means that while you don’t get full capacity out of the lifepo4, it never fully charges which dramatically increases the lifepo4 lifespan.