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If you build it, they will come..


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#1 Happysat

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Good

Posted 5 November 2014 - 15:09

Hey guys,

 

I did build from leftover shit sewer pipes an QFH antenna:

 

qfh_antenne.jpg

 

For weathersat reception of NOAA/Meteor* on the 137 MHz band with the cheap ass RTL-SDR 820 USB DVB-T sticks.

 

*Howto -> http://www.rtl-sdr.c...images-rtl-sdr/

Gallery https://dl.dropboxus...teor/index.html

Antenna http://sdrformariner...s-antennas.html

 

Anyway, during weathersat reception of NOAA/Meteor on the 137 MHz band i did see quite often unidentified interrupting signals. 

After a bit of Googling around I learned that these were Dead Satellite’s that still are broadcasting given the right sunlight conditions, the signal strength is sufficient to show up in SDRSharp ( http://sdrsharp.com ), not all signals are very strong some very weak and needed a good close up zoom in SDRSharp.
 
Attached File  Alouette.jpg   181.39KB   5 downloads
 
There are many shutdown Satellite’s who apparently having a life of their own varying from Military, Navigation, Experimental, Weather, and also Amateur ones.
 
Attached File  Tiros-N.jpg   134.6KB   5 downloads
 
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.
 
Attached File  Fenyung_1D.jpg   165.45KB   5 downloads
 
Most are not transmitting any usable telemetry or weather images but they still use the original frequencies to sent out a unmodulated carrier, which interferes with the current operational Satellite’s in the 136/138 MHz band.
Normally when a satellite goes out of service and runs almost out of fuel the last reserve is used to shift it in a graveyard orbit which resides above the normal operation orbit, it will be switched off and left on their own.
 
Attached File  ISIS-1.jpg   124.3KB   5 downloads
 
But this will not always goes as planned, sometimes due solar radiation or other technical failures it will not respond again to the ground station commands, which leaves the Satellite in its current orbit. 
Some have a timer onboard which will be activated at end of life scheduled to end/shortcut the power feed to the transmitter so it will not broadcast again, also this can fail.
 
Until some day they might not work at all anymore..
 
But that can take a while one of the oldest satellite still broadcasting are:
 
Transit 5B-5 (Military Navigation) from 1964 – http://www.satellite...ransit_5b-5.htm they can be heard in either CW or USB mode. 
 
Attached File  Transit5b-5.png_Full.jpg   195.04KB   5 downloads
 
An audio example of Transit is over here https://dl.dropboxus..._2014_09_06.rar (my recording) it sounds like some kind of melody song.
 
Attached File  Transit5b-5.jpg   154.2KB   5 downloads
 
And LES-1 from 1965 (Lincoln Experimental Satellite 1) -http://www.ufogeek.c...twatch/les1.htm .
Audio example over here  ( https://dl.dropboxus...1plainaudio.rar ) thanks to Phil Williams.
 
Attached File  LES-1.jpg   165.79KB   5 downloads
 
Others are just a spooky hauling sound like LES-1, NOAA’s etc due the Voltage fluctuation from the solar panels.
 
Attached File  NOAA-9.jpg   149.07KB   5 downloads
 
Attached File  NOAA-9_2.jpg   171.75KB   5 downloads
 
DD1US does have a very nice collection images and orginal sounds on : http://www.dd1us.de/...esounds 4b.html
 
A list of frequencies and more in depth details can be found on Mike Kenny’s excellent website: http://mdkenny.custo...u/emitters.html
 
My TLE containing all current Deadsatellite’s is available on dropbox for anyone would like to try out https://dl.dropboxus...tle/deadsat.txt
Updated once a week.
 
Attached File  Gpredict.jpg   145.81KB   5 downloads
 
You can use it in your favorite tracker, i prefer Gpredict for this ( http://sourceforge.n...ojects/gpredict ) course of the unstable frequency and Doppler effects Orbitron will not always suite on this birds.
 
I also provided a frequency database for SDR# containing the frequencies of all the dead satellites.
 
So lessen your mothers shame and pull out the dvb-t stick at the back of your Satellite receiver and enter a new world of fun  :)
 
Kind regards Happysat and blame it on the drivers offcourse  ;)  :lol:
 

Octagon SF8008 / TBS5530  DVB-S2/T2 T-85/1.50Mtr/3x90cm (53e 52e 51,5e 28e 25,9e 23e 19e 13e 9e 4e 1w 5w 14w)


Re: If you build it, they will come.. #2 MiLo

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Excellent

Posted 5 November 2014 - 18:34

That's the way to go, exercise your constitutional right on free signal reception! :)

Never knew what a QFH was, learn something new every day...
Real musicians never die - they just decompose

Re: If you build it, they will come.. #3 Erik Slagter

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+541
Excellent

Posted 5 November 2014 - 19:02

Happysat was on hackaday today!


* Wavefrontier T90 with 28E/23E/19E/13E via SCR switches 2 x 2 x 6 user bands
I don't read PM -> if you have something to ask or to report, do it in the forum so others can benefit. I don't take freelance jobs.
Ik lees geen PM -> als je iets te vragen of te melden hebt, doe het op het forum, zodat anderen er ook wat aan hebben.


Re: If you build it, they will come.. #4 Happysat

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+43
Good

Posted 6 November 2014 - 00:43

Milo, there is a saying from the famous Radio amateur Judica-Cordiglia brothers, when you want to have a optimal performance reception from a specific satellite one should build the exact same type antenna as the satellite itself is using to broadcast:

 

Attached File  Meteor_M-N2.jpg   601.74KB   4 downloads

 

Those Qfh antenna's can receive any signal from any direction and its performance is very good when a satellite pass comes overhead.

 

Yes Erik to my big suprise i didnt know they did take over the howto from RTL-SDR ;)


Edited by Happysat, 6 November 2014 - 00:44.

Octagon SF8008 / TBS5530  DVB-S2/T2 T-85/1.50Mtr/3x90cm (53e 52e 51,5e 28e 25,9e 23e 19e 13e 9e 4e 1w 5w 14w)



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