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Cake day: February 21st, 2024

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  • However you go about it, keep it simple. If it’s complicated or a chore to do, compliance will likely fall off and you might not maintain it.

    I do the YMD thing with folders, but fail to do the text file; it’s not a deal killer for me, but there are times we have to figure out what on earth we were doing. We can get a lot of contextual clues from the photos themselves. Depending on what you’re shooting, establishing shots can be really helpful.









  • Great questions, one which highlights my own knowledge gap beyond knowing that for a given feedline and antenna combination, you’ll have some measure of impedance. At the most basic level, your radio will “see” some impedance value. In the amateur radio world this is generally 50Ω. If our antenna system (feedline + radiator) presents 450Ω (quite common), we use a 9:1 transformer to get it to match. This allows us to use our radio on that system without (1) stray current returning to the radio and damage our transmission circuits, and (2) at full power but with inherent loss of signal owing to antenna inefficiency.

    Case in point, I have a commercially-purchased multi-band EFHW antenna which presents varying amounts of impedance to the radio. This system includes a transformer (I think it’s 9:1) so that on the bands of interest, there’s a resistance match and as a result an SWR that’s suitable to make decent transmissions on.

    As a tangential example, J-pole antennas have a built-in matching system which uses no special parts. It’s composed of a matching section and radiator. The combination of matching section, radiator length, and physical feedpoint allow this type of antenna to sort of self-manage impedance.

    The difference here is that a j-pole is a monoband antenna, and a long wire with transformer can often be functional on many bands, depending on length, where the lowest useable frequency is the inverse of its length.









  • 667@lemmy.radiotoSelfhosted@lemmy.worldremoved a homeplug
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    2 months ago

    One of the best no-noise locations I ever did was in a fully powered-down sailboat in the southern lagoon at Fort Jefferson, Dry Tortugas. Leaky consumer electronics are the worst.

    To contrast, I managed to work Indonesia from Alamogordo NM despite being in a residential neighborhood, HVAC capacitors and foreign over-the-horizon-radar (OTHR) be damned. Taught me a lot about being patient and picking out transmissions in the noise.