433 MHz ISM Band Through the "Eye " of the SDR Dongle

[spongella]

There are a couple of ISM (Industrial, Scientific, Medical) bands inhabited by low power wireless devices such as wireless car keys, remote weather stations, wireless wall switches, etc. One in use in the USA is the 433 - 434 MHz band. You probably have some device at home using this band.

Hooked up my dongle (okay.......my RTL-SDR dongle that is) to a dual-band ham antenna (2m/70cm) located high atop a building where I work and let it run for a while to "see" what signals were being transmitted from wireless devices. Even though they are low power, the dongle detected some strong, some weak ones.

See attached waterfall. Interesting stuff.

I hope my boss is not reading this......

 

[. Raine]

There are a couple of ISM (Industrial, Scientific, Medical) bands inhabited by low power wireless devices such as wireless car keys, remote weather stations, wireless wall switches, etc. One in use in the USA is the 433 - 434 MHz band. You probably have some device at home using this band.

Hooked up my dongle (okay.......my RTL-SDR dongle that is) to a dual-band ham antenna (2m/70cm) located high atop a building where I work and let it run for a while to "see" what signals were being transmitted from wireless devices. Even though they are low power, the dongle detected some strong, some weak ones.

See attached waterfall. Interesting stuff.

I hope my boss is not reading this......

Spongella, What software are you using? The software I've been using is a bit buggy, it works sometimes, sometimes I have to mess with it a bit to get it to work. I don't remember off-hand what software I have and I'm not on that computer right now to check, but my dongle is a NooElec R820T2 SDR & DVB-T NESDR Mini 2.

A friend of mine was over here a while back when I was messing with the SDR on my computer and he wants to try out a SDR dongle like mine to hear planes from the local airport [he's a retired pilot] but I know if he tries it with the software I'm using, the dongle will be flying across the room before long! He uses windows. If you know of any good Linux SDR programs, I'd be interested in that. What SDR dongle do you use too?

Thanks!

 

[KE4EST]

That screen shot is SDR#, the same one I use.

 

[Titanium]

+1

I almost exclusively use SDR#. Once you set the sensitivity for a band, it is easy to use. My wife listens to FM radio on the HTPC with SDR. She even has set up a favorites list... I haven't even tried that!

 

[mikelib]

I use SDR# with SDRPlay and the many dongles I purchased.

I down load weather satellite photo's from the NOAA satellites.

 

[mikelib]

I built a quadrifilar helicoidal antenna just for NOAA satellite reception and I use it for 2 meters. The picture is the a 2 meter + NOAA reception antenna with a 440 section on top which I will try to make contacts via HAM Radio satellite, as soon as it gets a little warmer.

 

[spongella]

Spongella, What software are you using? The software I've been using is a bit buggy, it works sometimes, sometimes I have to mess with it a bit to get it to work. I don't remember off-hand what software I have and I'm not on that computer right now to check, but my dongle is a NooElec R820T2 SDR & DVB-T NESDR Mini 2.

A friend of mine was over here a while back when I was messing with the SDR on my computer and he wants to try out a SDR dongle like mine to hear planes from the local airport [he's a retired pilot] but I know if he tries it with the software I'm using, the dongle will be flying across the room before long! He uses windows. If you know of any good Linux SDR programs, I'd be interested in that. What SDR dongle do you use too?

Thanks!

Software is SDR#, dongle is the one sold by RTL-SDR.com. You can use those to hear planes at 108 - 136 MHz using AM. Your NooElec is a good dongle to use. You have to first install a driver called Zadig, then you can use SDR#. Not sure about Linux programs but there is one called GQRX.

 

[spongella]

+1

I almost exclusively use SDR#. Once you set the sensitivity for a band, it is easy to use. My wife listens to FM radio on the HTPC with SDR. She even has set up a favorites list... I haven't even tried that!

Titanium what she is using is SDR#'s Frequency Manager option, it stores your favorite frequencies and has unlimited memory. Nice feature.

 

[Titanium]

I added the metal enclosure to the NooElec. Helped control the noise and looks much better than the aluminum foil wrapping!

 

[spongella]

One thing forgot to mention - if you switch your dongle to a different USB port on your computer, it may not work and all you would need to do is reinstall the Zadig driver. No need to reinstall SDR# though, it is not affected.

 

[KE4EST]

One thing forgot to mention - if you switch your dongle to a different USB port on your computer, it may not work and all you would need to do is reinstall the Zadig driver. No need to reinstall SDR# though, it is not affected.

Found this out the hard way one day, after hours of pulling out my hair!!!

 

[. Raine]

Software is SDR#, dongle is the one sold by RTL-SDR.com. You can use those to hear planes at 108 - 136 MHz using AM. Your NooElec is a good dongle to use. You have to first install a driver called Zadig, then you can use SDR#. Not sure about Linux programs but there is one called GQRX.

Thanks a lot, I'll check into SDR# and GQRX. Thanks for the frequency range too, that will help, he'd told me just 117 mhz [if IIRC] and one other, but he didn't know the full range. I think SDR# may be one of the programs I already have, I'll have to check.

The computer I have the SDR on is dual boot Win7 and Linux and I hardly ever use the windows on it, the SDR is one of the few things that I've kept the windows partition for. I'll probably get rid of it completely on that computer and set up a dedicated computer just for the SDR and the few other things that I still use windows for. I use the win 7 so little that whenever I boot it up into windows, it needs to do a gazillion updates and it's always like an half hour before I can actually do anything on it, very annoying and it's actually replaced the Zadig driver on me a few times too. I've done a lot of funky code on the win partition too, so maybe a clean install of win would help.

Actually, what OS do you use? I haven't installed or worked on any beyond Win7 because Media Center was going into a direction I didn't like, but MS still sends me every release, so I have all of them.


Thanks, thanks everyone else too! Much appreciated!

 

[spongella]

I hear you about the gazillion updates; few years ago had a desktop that was unused for a few years, then when I plugged it in after that 3 year hiatus I think it took close to 8 hours for all the updates.

When you plug in the SDR dongle for the first time on a computer, Windows will install it's own driver, which is of no use for SDR - that is when you use Zadig to install the correct driver. And yes, sometimes the correct driver gets uninstalled for no reason, happens sporadically, best bet is to make a shortcut on your desktop for Zadig just in case.

Current OS is Windows 8.1.

Nooelec enclosure looks real nice, well made and nice blue color. Great company.

SDR# software download is now on the Airspy website.

 

[spongella]

I use SDR# with SDRPlay and the many dongles I purchased.

I down load weather satellite photo's from the NOAA satellites.

View attachment 115016

Beautiful photo Mike!

 

[spongella]

A Raine, most of the comms from pilots seem to be in the region of 118 - 136 MHz in the aero band. Attached is a screenshot of air comms this morning. Note that this is not the SDR dongle, it is the HackRF One, which shows a 9 MHz span. The HackRF One is like an SDR Dongle but on steroids. But you'll get the same reception using an SDR dongle. Use AM and crank up the RF gain to the max.

Maybe we have some pilots on the forum that can give us tips on listening?

 

[. Raine]

A Raine, most of the comms from pilots seem to be in the region of 118 - 136 MHz in the aero band. Attached is a screenshot of air comms this morning. Note that this is not the SDR dongle, it is the HackRF One, which shows a 9 MHz span. The HackRF One is like an SDR Dongle but on steroids. But you'll get the same reception using an SDR dongle. Use AM and crank up the RF gain to the max.

Maybe we have some pilots on the forum that can give us tips on listening?

Thanks again! I'm hoping to get a chance to do a clean install of windows on one of the unused computers here sometime this week and then hopefully get the time to play around with it this coming weekend.

What's a good antenna to use for AM? The dongle came with a little telescopic antenna that's 12-1/2" tall when fully extended and I picked up the FM band good with it when I was messing with the dongle before, but is that antenna good for AM too?

 

[spongella]

When you say AM do you mean the AM broadcast band (530 - 1710 KHz) or AM in the aircraft band (108 - 136 MHz)?

 

[. Raine]

When you say AM do you mean the AM broadcast band (530 - 1710 KHz) or AM in the aircraft band (108 - 136 MHz)?

Oops, sorry! I mean the aircraft band, 108-136 Mhz.

 

[spongella]

If you are a ham and have a 2m antenna it'll be a little short for the aircraft band but you could try that. I use a discone antenna that covers 25 - 1700 MHz and it works fine.