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For a residential setting, installation quality probably dominates, and I doubt country of origin is statistically significant. Otherwise look at warranties which specify a performance curve over lifetime (generally 25y, also some are independently guaranteed by an insurance company that might actually survive that long). There are public performance datasets from NREL, TUV, but be careful about choosing representative examples (e.g. utility scale reliability is different from rooftop)

I think what you really want is an Energy Recovery Ventilator. It cycles in fresh air and uses an intercooler to limit the heat and humidity loss.


That’s cool. Is that something that you’ve built or installed?

Even if that is a better solution, I am personally curious about an indoor carbon dioxide zapper, since what I work on is carbon dioxide removal at planetary scale.


I haven't installed one yet, but plan to in my house. I'll probably end up buying an assembly, but they seem pretty spendy for what is really a very cheap BOM.


I would actually expect the math to decode ads-b traffic is substantially less complex than, for example, a TLS connection.


TLS is supported in hardware, so it takes no more processing power than moving the data around without encryption.

In the US, ADS-B in uses 1.3 MHz of bandwidth, which would require 2.6 Msps. The ESP32-C3 running at 160 Mhz would have ~70 instructions per sample to process the data. That's probably doable, but the ESP32-C3 is one of the less capable variations of the line, and there are dual-core versions running at more than double the frequency, and those should be able to handle ADS-B in without issue.


> TLS is supported in hardware, so it takes no more processing power than moving the data around without encryption.

Specifically, common PC CPUs support AES acceleration, so you can get the ongoing encryption for an established connection with minimal overhead. There is still some initial overhead for establishing the TLS connection due to the need to do key exchange (with asymmetric cryptography primitives typically based on Diffie-Hellman with finite fields or elliptic curves).


GPS is over 1 GHz, but I don't think you need to have a microcontroller running that fast to decode it?


I imagine the over 1GHz in this case is the baseband that you are talking about.

ADS-B baseband is also around 1GHz, what they mean is once you down convert in the process of demodulating the signal you will get a signal that has bandwidth of 1.3MHz.


It's the width of the band that matters, not the carrier frequency. For example a band running from 1.21 GHz to 1.22 GHz has a 10 MHz wide band. A heterodyne tuner would use analog circuitry to output it as a 0 to 10 MHz baseband signal that can the be sampled by the ADC.

GPS bands are from 11 to just over 15 MHz, depending on the band, but decoding is extremely complex, so it's usually done with dedicated hardware, so a microcontroller only needs to read the handful of bytes that hardware outputs per update, and most receivers default to only a single update per second, and max out at tens per second.


Except on small memory / processing devices (like ESP32) it's not actually that simple. Processing ADS-B on an ESP32 would, likely, be easier.

Part of the reason I've come to understand how finicky TLS is on ESP32 is because there have been a ton of TLS issues with these devices in Home Assistant [0]. The linked issue just being one of them that's still not fully resolved.

[0] https://github.com/esphome/home-assistant-voice-pe/issues/31...


It is trivial to decode, but don’t forget that tls is extensively optimised on most networking stacks.


The max steering angles of the phased arrays are much higher, the diameter is at least 10x what you say. And for the last few years, lasercoms can route traffic inside the constellation so a given sat doesn't need to be within sight of a ground station.


>The max steering angles of the phased arrays are much higher

You can't steer the antenna back and forth for every exchange between station and customer. What the steering may get you is increasing the coverage of an area currently underserved by the constellation, and maybe a slight increase in diameter of ground covered due to the geometry, at the cost of lower signal strength.

>And for the last few years, lasercoms can route traffic inside the constellation so a given sat doesn't need to be within sight of a ground station.

Did they finally implement satellite-to-satellite links? Fine, if that actually works, they can indeed extend the range much further. I don't know if I believe it, though.


https://mikepuchol.com/modeling-starlink-capacity-843b2387f5...

You can read this article. The lasers worked before February 2022, but you don't require them to have multiple spot beams.


The parent is correct. Look up have many antennas are on each Starlink sat. There are multiple dedicated antennas for customers and ground stations. There isn’t just one antenna or beam per satellite.

Also, lookup the number of ISLs in orbit. Starlink has been providing coverage for the middle of the ocean for years now. They have provided coverage to Pacific Islands that have lost their undersea cable connections.


> You can't steer the antenna back and forth for every exchange between station and customer.

Even ignoring that they have multiple arrays, they use separate antennas to talk to the base stations on a different frequency band.


Your ignorance is only exceeded by your unwillingness to learn.

“if that actually works”??? It has been working successfully for large parts of the Earth for years.


On the platforms I've worked with, the weight isn't the issue so much as the quantity of expensive and vibe sensitive parts that are unsprung.


The doubt is supposed to stay with you! You need to make sure there aren't other causes or contributing factors hiding behind 'the obvious'. There have been notorious cases in spaceflight where the issue was 'identified' and 'fixed', only for the same thing issue to happen in the next mission.


> There have been notorious cases in spaceflight where the issue was 'identified' and 'fixed', only for the same thing issue to happen

In software development this is your average weekday.


Seconding this! Make sure you get the "special tour". It was an absolute highlight of my trip. If you are interested in power infrasture it's a must see. If you're afraid of heights, perhaps not so much.


Could you kindly elaborate on the "afraid of heights" aspect? Was there a lot of catwalks or anything of that nature?


There is one part where you are invited to walk on a catwalk that's very high up (an outdoor staircase sort of like a fire escape). My recollection is that walking on it is not mandatory for the tour, but I'm not absolutely certain of that.

You're also invited, but not required, to look over the edge of the dam from the top, which is also very far down.


This is correct. If you don't like heights, that's definitely not a reason to skip the tour, but you'll miss out on one piece (that I enjoyed).


JetBlue is a small rival (JetBlue at ~5% of US traffic, Spirit at ~3%) to the big 4 United/American/Southwest/Delta (each with ~17%). At least on the surface, a larger JetBlue might be more competitive rather than forcing them into the unequal partnerships like they have with United at the moment. Certainly, some jobs would be lost, but I do think that Spirit dying is a worse outcome than joining another small airline.


This is actually what is thought to partially have caused the damage seen previously. The new trajectory is supposed to just have a single heating pulse instead of two.


Well, the IRGC folks actually fighting probably don't have a luxurious future in a reformed Iran, so they might not be far off fighting for their lives.


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