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

WebSDR – Internet-connected Software-Defined Radios

websdr.org

Post reply on HN
Print view View original

21–30 of 67 posts

Re: WebSDR – Internet-connected Software-Defined Radios

#21

Post by galangalalgol »

reactordev wrote: post #19
galangalalgol wrote: post #18

Earlier quoted context omitted.

An airspy can digitize 12MHz of bandwidth at once. Even without a gpu you can spit out easily over a dozen digitally subtuned channels. The bandwidth for all that raw signal data going out would be the problem. Only one person can control where that 12MHz is centred, but people can pick where in it they want to listen just like they do with websdr now.

Damn! Yes, you would need to have one user center the spectrum read and you can mux the output to users wanting specific bands but I had no idea an airspy had such a wide audio capture. Edit: I looked it up. You are indeed correct. 10MSPS IQ output. 10Mhz panorama spectrum view. That’s ridiculous! I just bought one.

I think the boxy one, the r2 not the mini, had some hacky way to get 80msps but it didn't specify how that made it over usb or why that wasn't the normal operational mode.

Re: WebSDR – Internet-connected Software-Defined Radios

#22

Post by mikewarot »

galangalalgol wrote: post #18
reactordev wrote: post #17

Earlier quoted context omitted.

The perceived stagnation in the field is because you can’t multiplex an SDR stream. One user can control the radio at a time. You can not listen on more bands than your radio can receive at once. Capping out at 192hz band audio sampling on most hardware. Which means you can read a wide signal but you can only read one area of the spectrum at a time. You would need more radios. If you added more radios you would need…

An airspy can digitize 12MHz of bandwidth at once. Even without a gpu you can spit out easily over a dozen digitally subtuned channels. The bandwidth for all that raw signal data going out would be the problem. Only one person can control where that 12MHz is centred, but people can pick where in it they want to listen just like they do with websdr now.

Even a $30 RTL-SDR dongle can record 2Mhz of bandwidth reliably. I've recorded hours of signals just in case it sometime later becomes interesting, and it all lives in a little corner of my hard drive.

Re: WebSDR – Internet-connected Software-Defined Radios

#23

Post by nomel »

weissbier wrote: post #4
riffic wrote: post #2

it's still closed source software? previously: https://news.ycombinator.com/item?id=18571139

If you want to have something similar for use at home, you could take a look at http://kiwisdr.com . I have one, but you need to hunt down EMI sources, before you can properly use it.

> but you need to hunt down EMI sources, before you can properly use it.

Do you have any recommendations for doing this? I have some source that interferes every 11 seconds for a second or so. It causes packet loss with my wifi (2.5 and 5GHz), and makes my bluetooth game controllers really frustrating to use, since input are missed every time it does it. I assume it's in the microwave range.

I'm familiar with RF test equipment, and I've thought about renting a spectrum analyzer, but I assume there's maybe some cheaper way.

Re: WebSDR – Internet-connected Software-Defined Radios

#25

Post by op00to »

desertraven wrote: post #20

This is a cool project. I bought both a HackRF and an Ettus USRP B210 years ago for playing with. I am yet to actually do anything of interest! Anyone want to share anything cool they’ve done in the SDR world?

I have a pm2.5 sensor that hooks to a weather station I don’t have. I am using a cheap SDR to grab the data over the air and dump it into a mqtt topic for consumption in home assistant. Standing on the shoulders of giants and all, but it’s still pretty neat.

Re: WebSDR – Internet-connected Software-Defined Radios

#26

Post by ge96 »

desertraven wrote: post #20

This is a cool project. I bought both a HackRF and an Ettus USRP B210 years ago for playing with. I am yet to actually do anything of interest! Anyone want to share anything cool they’ve done in the SDR world?

Not me but this was neat and interesting (after using SDR to capture)

https://www.youtube.com/watch?v=EFLvHMJ5PHk

Re: WebSDR – Internet-connected Software-Defined Radios

#27

Post by heywire »

desertraven wrote: post #20

This is a cool project. I bought both a HackRF and an Ettus USRP B210 years ago for playing with. I am yet to actually do anything of interest! Anyone want to share anything cool they’ve done in the SDR world?

I use rtlamr to receive and record my natural gas usage, and I wrote some code to receive my water usage from my water meter (though I’ve since moved that code to an Adafruit Feather w/ an RFM69 module).

Re: WebSDR – Internet-connected Software-Defined Radios

#28

Post by _whiteCaps_ »

If you're looking for chatter, check out https://pota.app and filter by SSB. You'll hear people making contacts for the Parks On The Air program.

10m (28MHz) has great propagation right now during the day so you'll hear people talking across great distances, like California to Japan or Australia.

Re: WebSDR – Internet-connected Software-Defined Radios

#29

Post by deltasepsilon »

For those interested in SDR, there was recently a discussion here on signals identification [1], and some months ago a discussion of NXP's new LA9310 ADC chip for radio applications [2]:

[1] https://news.ycombinator.com/item?id=37869534

[2] https://news.ycombinator.com/item?id=35325165

Re: WebSDR – Internet-connected Software-Defined Radios

#30

Post by jcims »

desertraven wrote: post #20

This is a cool project. I bought both a HackRF and an Ettus USRP B210 years ago for playing with. I am yet to actually do anything of interest! Anyone want to share anything cool they’ve done in the SDR world?

Those are both extreme overkill for the task but participating in ADSB networks for sites like flightradar.

I really enjoyed making antennas and capturing data from satellites.

Getting trunking receivers (eg unitrunker) to listen to local first responder radio.

Decoding pagers is fun

As others have said, decoding various devices that talk on the various ISM bands is interesting.

Just band surfing at night is a lot of fun imho. Finding random signals and trying to figure out what they are is cool.

Post reply on HN