• 10 Posts
  • 661 Comments
Joined 4 months ago
Cake day: June 23rd, 2024
  • ChaoticNeutralCzech@feddit.orgtoScience Memes@mander.xyz•Publishers Always InnovatingEnglish
    2·
    6 hours ago

    Well, you have a lot more experience than I do. I don’t think I can provide good advice but the idea of another circuit borking it is interesting, I’d put voltmeter(s) on the supply voltage(s) of the deflection circuit and check for changes.

    Please don’t call the unit “CRT”, it’s weird to read phrases like “when the CRT is apart” because you can’t really make a tube work again if it’s been apart.

    However, it makes me think if one could smash all tubes in a vacuum tube TV in the vacuum of space or one big glass chamber and have it still working. Or build a monitor into a tube that looks like an overly long CRT but just needs power and video. Maybe even include an IR remote receiver for digital picture adjustment. This is way beyond what I will ever be able to do, though, and there is little reason to make this gimmicky thing that is worse than Philips Predicta in almost every way.

  • ChaoticNeutralCzech@feddit.orgtoScience Memes@mander.xyz•Publishers Always InnovatingEnglish
    4·
    7 hours ago

    I assume datasheet websites just have pages for every combination of 3-12 alphanumerics to appear in search results, and then use shitty fuzzy string matching tactics to find “most relevant” items. It would help if they managed to extract package marking codes from datasheets so you can find SOT-23 parts by their 2-3 character codes, or whatever obscure system used by individual IC manufacturers. I think they have resources to make the experience way better but they prefer to turn high profits. Personally, I would not mind trying AI (not neccessarily a LLM) for the data extraction but I’d be cautious and only release it if it is decently reliable (but I know they wouldn’t bother with that).

  • ChaoticNeutralCzech@feddit.orgtoScience Memes@mander.xyz•Publishers Always InnovatingEnglish
    3·
    8 hours ago

    Pretty sad that a technical manual for the monitor was most likely created but just not digitized in a way you can find. Intermittent faults are very hard to diagnose. What I would try:

    • I assume you’ve cleaned the potentiometer, which is also easy to check with an ohmmeter (mind the polarity or desolder it to protect the rest of the circuit).
    • Poke the circuit board with a non-conductive object to find loose solder joints or components with bad contacts inside. If the fault is not mechanical, it might be an overheating component.
    • Try adding a fan temporarily to see if the fault appears later, or use a thermal camera to find semiconductors that might go near their threshold temperature (150 °C for the silicon die).
    • Find points in the horizontal deflection circuit where voltage or waveform changes as the fault manifests.
  • ChaoticNeutralCzech@feddit.orgtoScience Memes@mander.xyz•Publishers Always InnovatingEnglish
    58·
    8 hours ago

    Datasheet websites do that a lot. If it’s PDF.js, Firefox’s PDF viewer (or a fork of it), I just right-click to “Show only this frame” and it goes fullscreen. It might have shenanigans such as disabled printing but you can press Ctrl+Shift+E and reload to check network activity for what address the PDF is loaded from and save that.

    The worse ones are PDFs that exist only for SEO and contain nothing but keywords and a link to a paywall.

  • ChaoticNeutralCzech@feddit.orgtoBedfordshire@feddit.uk•Why can you see Northern Lights better on your phone than with your eye?English
    4·
    3 days ago

    All but than the last two paragraphs are filler, and the penultimate one is common knowledge. Only the last one matters:

    So, when the sun sets and night arrives, our eyes lean more heavily on the rods and it is why colours don’t pop the same way as they do during the day time. In low light, the website explains, our eyes prioritise motion detection and shape recognition so you are able to navigate more easily - and this is why auroras often appear invisible to the naked eye.

    Oh well, I thought there was an overwhelmingly strong near-IR component but that would appear pink in the camera, not red or green.

    By the way: if you can only see a dim star in your peripheral vision, blame the high concentration of cone cells in the eye’s yellow spot (visual field centre).