• 0 Posts
  • 33 Comments
Joined 1 year ago
cake
Cake day: February 1st, 2024

help-circle
  • ZigBee router thing:

    I’ve been happy with the SMLIGHT SLZB-06M. You can easily flash firmware, and it has PoE which was important for me. I believe it also supports Thread, but I haven’t tried this yet (and I’m not sure if it supports it at the same time as Zigbee).

    Zigbee smart plugs from Third Reality have been pretty solid in my experience, and they report power usage.

    For circuit breaker level monitoring, I have an Emporia Vue2. I have it running esphome, completely local — unfortunately this requires some simple soldering and flashing, so it’s not turnkey. But it’s been rock solid ever since flashing it. (Process is well documented online.)

    I’ve had decent luck with cheap wifi Matter bulbs, but provisioning them is finicky, and sometimes they just crap out and need to be power cycled; Zigbee bulbs (e.g., Ikea) have generally been reliable, though sometimes I’ve had difficulty pairing them initially. After power cycling a Matter WiFi bulb, it takes a while for it to respond to Home Assistant; Zigbee bulbs generally respond as soon as you power them on.

    I have a wired smart light switch from TP-Link/Kasa (KS205), and it’s been completely hassle free (and totally local — Matter over wifi). The Kasa smart switch dongles I have work flawlessly but need proprietary pairing, and I’m afraid to update firmware in case they lose local support.

    Good luck! Fun adventure :)




  • That’s…not really a cogent argument.

    Satellites connect to ground using radio/microwave (or even laser), all of which are electromagnetic radiation and travel at the speed of light (in vacuum).

    Light in a fiber travels much more slowly than in vacuum — light in fiber travels at around 67% the speed of light in vacuum (depends on the fiber). In contrast, signals through cat7 twisted pair (Ethernet) can be north of 75%, and coaxial cable can be north of 80% (even higher for air dielectric). Note that these are all carrying electromagnetic waves, they’re just a) not in free space and b) generally not optical frequency, so we don’t call them light, but they are still governed by the same equations and limitations.

    If you want to get signals from point A to point B fastest (lowest latency), you don’t use fiber, you probably use microwaves: https://arstechnica.com/information-technology/2016/11/private-microwave-networks-financial-hft/

    Finally, the reason fiber is so good is complicated, but has to do with the fact that “physics bandwidth” tends to care about fractional bandwidth (“delta frequency divided by frequency”), whereas “information bandwidth” cares about absolute bandwidth (“delta frequency”), all else being equal (looking at you, SNR). Fiber uses optical frequencies, which can be hundreds of THz — so a tiny fractional bandwidth is a huge absolute bandwidth.






  • It is really powerful per watt, and has a built-in UPS. Any homelab type things you could do with that? macOS+homebrew will give you a nice *NIX feel, very familiar if you’re a Linux user.

    I’m a fan of having a remote homelab computer+disk for off-site storage. This would be a good candidate in that it wouldn’t use excessive power at a friend/family’s place, but may be overkill (I use a pi3 for that).







  • Same — rsync to a pi 3 with a (single) ZFS drive at family’s house. Retain some daily/weekly/monthly snapshots.

    I have a (free) VPS with static IPv4 which is how I connect everything.

    Both the VPS and the remote site have limited network speed (I think 50Mbps for VPS), so the initial sync was done sneakernet (well…“airplane net”). Nightly rsync is no problem bandwidth-wise, and is mostly just any new videos I’ve uploaded to my local Immich instance.





  • Yes. But why is there an absence of light?

    If there are infinite stars, then every direction you look would encounter a star. (Things stay the same brightness per subtended angle as they get far away. Space dust doesn’t matter, as it would thermalize and radiate.)

    So, the universe can’t have infinite luminous matter, be static and ageless, because if it were then the night sky would look like the surface of a sun.

    This may all seem obvious, but it’s neat that you can figure that out with the naked eye.