ADS-B is for sissies: Receiving Dead Satellites with the RTL-SDR

[LexMichdeappel]

I came across something I think is really awesome and I'm sure there are some of you you also are freaked out by this little gem.

http://www.rtl-sdr.com/receiving-dead-satellites-rtl-sdr/

So there are sattelites up there that should have been crashed, but somehow didn't (because of comm failures and such) and are still beaming stuff around.

Although these satellite’s batteries have long been expired, because of some sort of chemical reaction due to thousands of failed recharge cycles the batteries begin to conduct over time and allow the satellite to be powered directly from the solar panels thus activating the transmitter.

Some more interesting stuff: http://mdkenny.customer.netspace.net.au/emitters.html

Launched on 13 Dec 1964 as the second operational TRANSIT spacecraft, it should be more correctly called OSCAR -2, O-2 or NSS 30020. Unfortunately, the navigation system failed within 2 weeks of launch. The telemetry beacon can be CW or modulated depending on solar lighting conditions. The PAM data is 35 steps with a repeat cycle of about 12.5 seconds. Each step has a duty cycle of about 75% data value and 25% return to centre frequency value. These steps vary a 5400 Hz centre frequency sub carrier oscillator, IRIG 10, that then frequency modulates the RF carrier. Another SCO at 10.5 kHz, IRIG 12, is sometimes present. It has a pattern of five pulses with gaps, followed by a longer gap at about a 1.5 Hz rate. A SSB receiver will resolve, separately, the carrier as a single tone and each of the sidebands as "musical" tones.

So this 50 year old piece of space "scrap" can still be heard!

Hoping to see some more results coming in from other RF enthousiasts. ADS-B is for pussies!

[cooper]

Fascinating stuff, but is this a matter of "Hey, I'm receiving something. See that spike on the waterfall?" or "Hey I'm receiving data which, when interpreted such and such way equates to this snippet of information as provided by that satellite".

In other words, are they receiving 'signal' or are they receiving 'data'?

[LexMichdeappel]

For some signal is enough.

[bytedeez]

I disagree, i receive wifi, blue tooth signal from all kinds of APs when pentesting. I'm not after the signal, I'm after the data. Although receiving satellite signal is out of the ordinary for most people, if it is just a signal. it's cool at first (for about 2 secs.) but boring in the long run.

[LexMichdeappel]

I disagree, i receive wifi, blue tooth signal from all kinds of APs when pentesting. I'm not after the signal, I'm after the data. Although receiving satellite signal is out of the ordinary for most people, if it is just a signal. it's cool at first (for about 2 secs.) but boring in the long run.

Then this just isn't your fetish.

[ZaraByte]

This kinda sounds cool but i haven't even gotten my feet wet with ADS-B Stuff yet total nooblet i made one video on tracking basic aircraft with the dongle hak5 sells but something like this is mind rape i'd wanna need to take a toke of some pot to be able to focus i just can't focus to wanna read and read and read. I like to teach people by videos.

I'm, the kinda person who learns faster from seeing it being done.

Edited November 5, 2014 by ZaraByte

[sud0nick]

I just came across this article myself and I have to agree with some of the other posts here. It is really interesting to listen to the signal but unless if you can receive data it only stays cool for a few seconds. I did find this part interesting though:

Most are not transmitting any usable telemetry or weather images but they still use the original frequencies to sent out a unmodulated carrier...

While the original article is littered with grammatical errors, and I may be reading it incorrectly, I gather from this statement that data is still being sent because that's exactly what a carrier wave does. He does state, however, that most are not transmitting any usable imagery but I wonder what he means by this. Does he mean the imagery is outdated or it merely doesn't exist? Also where would these decommissioned satellites be pulling their data from anyway? If you could determine that actual imagery can be derived from the signal you would probably need special equipment to see any of it. I think these dead satellites are really only good for a listen; some of them are even musical like Transit 5B-5. If you download the file that the author recorded there is a spot in the middle where I swore the bass was about to drop.