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by dspillett 853 days ago
If basic radio worked for talking between suits and the landing craft in '69, it surely shouldn't be a surprise that modern frequency-hopping, error corrected, wireless comms, with much more sensitive equipment would work well?
2 comments

The walkie-talkie toys I had as a kid in the 90s had at least 10x the range of modern home wifi routers. Not to mention how far radio stations broadcast. I'm guessing that's the context they're working from.
That's because of different frequencies and power caps that are enforced by the FCC. If your WiFi broadcast with the same power, the frequency space would be unusable by your neighbors for their WiFi. The range of WiFi is very purposefully sabotaged to make it useful for more than just you.
Assuming you are talking about FCC Part 15 regulations for 2.4 GHz, you couldn't be more wrong. There is no 'sabotage'

The EIRP is 4 watts in 2.4 GHz band. More than enough to wipe out your neighbors. Also more than enough to get absolutely tremendous range in line of sight conditions.

I can purchase and install an unlimited number of 2.4 GHz Part 15 devices, rendering the band useless to anyone so long as I am attempting to use those devices in a manner consistent with their application. As another Part 15 user, you have no recourse. If a licensed user complains to the FCC, they may decide I have to stop using them and notify me as such. Note: one of my neighbors does this, by having an AP on every 2.4 GHz and 5 GHz channel.

Newest Wifi 6 stuff in the US has a power limit on some spectrum and some usages, but nowhere near as low as what I was hoping for.

> Note: one of my neighbors does this, by having an AP on every 2.4 GHz and 5 GHz channel.

Sounds like a fun and ethical excuse to DOS some WIFI routers.

Why isn’t the limit 40 watts? Or 400? Why is there a limit at all?

You can pedantically criticize the use of the word “sabotage”, but then you’d be entirely missing the point.

400 watts would cause RF burns at 2.4 ghz.
And most people have a 1200 watt version in their kitchen for that exact purpose!
And also because our kid-era walkie talkies were VHF (or at least mine were) which is a much lower frequency band than wifi. At a given power level, lower frequencies travel farther (i.e. around obstacles) but can't transfer as many bits as wifi.
I wonder how much power the wifi antenna on the cubesat is pumping out.
And all of that without an appreciable atmosphere to get in the way