Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Radio Amateur Copies Signal from Mars-Orbiting Satellite

arrl.org

Post reply on HN
Print view View original

21–30 of 41 posts

Re: Radio Amateur Copies Signal from Mars-Orbiting Satellite

#21

Post by texasbigdata »

myth2018 wrote: post #8
geocrasher wrote: post #7

This is nothing short of incredible. Radio is hard, even at HF (1-30mhz). It's very forgiving at HF though, and so is very approachable. This is where I spend my ham radio time dabbling and hacking away at things. VHF is harder, and UHF an order of magnitude harder. But 8-12Ghz? That's not for mere mortals. It's machining pieces at tight tolerances and movement measured in the smallest fractions. If this is what he d…

I have no hands-on experience with homemade equipment for the GHz bands, but I've read that they are a bit less challenging than it seems at a first glance. Mostly because of the availability of GPS receivers providing highly stable, relatively cheap frequency references for transverters. Notice that I'm not saying this to demerit any achievement. My intention here is to be encouraging in case you intend to give it a…

As an outsider what’s the order of magnitude on humans that have this setup currently functional? 100? 1,000? Etc.

Re: Radio Amateur Copies Signal from Mars-Orbiting Satellite

#25

Post by DrAwdeOccarim »

texasbigdata wrote: post #21
myth2018 wrote: post #8

Earlier quoted context omitted.

I have no hands-on experience with homemade equipment for the GHz bands, but I've read that they are a bit less challenging than it seems at a first glance. Mostly because of the availability of GPS receivers providing highly stable, relatively cheap frequency references for transverters. Notice that I'm not saying this to demerit any achievement. My intention here is to be encouraging in case you intend to give it a…

As an outsider what’s the order of magnitude on humans that have this setup currently functional? 100? 1,000? Etc.

There are 774,562 amateur radio licensed people in the US [1]. I would assume 10% of them are super active, so 77,456, and of those super active people, I'd say 1% of them are pushing the boundaries. So 1000?

[1] http://www.arrl.org/fcc-license-counts

Re: Radio Amateur Copies Signal from Mars-Orbiting Satellite

#27

Post by myth2018 »

texasbigdata wrote: post #21
myth2018 wrote: post #8

Earlier quoted context omitted.

I have no hands-on experience with homemade equipment for the GHz bands, but I've read that they are a bit less challenging than it seems at a first glance. Mostly because of the availability of GPS receivers providing highly stable, relatively cheap frequency references for transverters. Notice that I'm not saying this to demerit any achievement. My intention here is to be encouraging in case you intend to give it a…

As an outsider what’s the order of magnitude on humans that have this setup currently functional? 100? 1,000? Etc.

That's a good question. I don't know how to estimate, but it might be around the thousands in fact.

Most of active hams are more interested on making short contacts and exchanging call signs. Scientific and technical experimentation is pretty niche. However, since the Es'hail-2 has launched (a Qatar geostationary satellite carrying an amateur radio payload on the GHz bands), a new opportunity of making a lot of short contacts using narrow band modes like Morse code and computer-aided modes has opened, and then I believe there are currently many people operating GHz-capable gear in the area covered by that satellite (Europe, Africa, parts of Asia and Brazilian northeast).

Although many of them are probably using their gear to log new contacts, you could say that they own the necessary setup to seek for satellite signals on that same band.

Re: Radio Amateur Copies Signal from Mars-Orbiting Satellite

#28

Post by rawoke083600 »

floatingatoll wrote: post #3

I wonder if ARRL knows there’s malicious ads on their site. Reader mode saves the day!

I'm pretty sure it's curse of HAM-Websites ! They either have malware or looks like frontpage2000 projects. Not dishing just noting ! Big fan of hams !

Re: Radio Amateur Copies Signal from Mars-Orbiting Satellite

#29

Post by treesknees »

As someone not familiar with ham - what can you do with this signal? Can you decode it to view stats or pictures? Or is it mostly just "hearing" it speak to Earth?

I'm also curious what prevents say an amateur operator or even another country from sending commands or disrupting communication to remote systems on Mars. Is it the just the amount of work they'd have to do, proprietary/secret protocol, encryption?

Re: Radio Amateur Copies Signal from Mars-Orbiting Satellite

#30

Post by chokeartist »

myth2018 wrote: post #13
schoen wrote: post #9

Earlier quoted context omitted.

Apparently the Deep Space Network dishes are (now up to) 34 meters: https://www.nasa.gov/feature/jpl/nasa-s-deep-space-network-w... I guess they achieve higher reliability than amateurs on a number of counts, but that contrast also makes the amateur efforts seem even more impressive. (Since area is proportional to the square of diameter, the DSN dishes would each be over 3,000 times larger than Scott Tilley's dish.)

Indeed, but there are other important factors besides size. DSN have way bigger requirements in terms of signal to noise ratios, since they need to demodulate received signals. Scott Tilley, on the other hand, seems to be mainly interested on detecting the presence of signals, not necessarily extracting information from it. Then, he could build a bigger dish, but he doesn't actually need one to achieve his goal. I no…

> I've always asked myself why spacecrafts "wasted" energy with carriers and never realized they make the signal easer to find.

Not exactly. You need a carrier wave / signal to modulate information onto. Can't modulate info onto nothing.

Post reply on HN