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Joined 2 years ago
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Cake day: June 23rd, 2024

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  • You could stream 144p6 video with phone-like audio with a RealPlayer browser plugin and a 28k modem in 1998. Very few websites served video but some TV channels were available live like this, maybe also in 240p15 at double the bitrate with a luxury 56k modem or ISDN. Viewers with slower modems could often download such videos as VODs (depending on copyright because those didn’t have RealPlayer DRM) as WMV (with Microsoft’s proprietary codec better than MPEG-2) or AVI (as MPEG-2 so you could burn it onto a CD and view on a DVD player but it’s unlikely you’d have a big disk and CD burner but processor too slow for that video). DVD-quality video (high bitrate 480p30/480i60/480p24/576p25/576i60, now considered low-end for movies) only became available to stream about 10 years later.














  • I’ll be assuming the pole is not grounded (electrically isolated from Earth, the earth pin of sockets, radiators, plumbing etc.)

    The difference is not DC vs AC but between it being connected across two screws, for which a high current source (hundreds of amps at negligible voltage) will heat the metal up - as opposed to connecting a voltage (like 120V mains for AC or 170V single-diode-rectified & smoothed mains for DC) referenced to ground to the pole. The former will draw a lot of current from the source through the screws and metal between them, heating it up. A car battery could briefly deliver hundreds of amps and several kW, making them glow red hot. The latter will create a potential between the pole and ground, which will only draw current when a load is connected between the pole and the ground. For AC, a person’s body’s capacitance to ground, even with insulating shoes, is enough to feel a tingle. For AC or DC of sufficient voltage (above 60 V), they will get a shock if they touch ground and the pole, completing the circuit.