Mars Reconnaissance Orbiter
The Mars Reconnaissance Orbiter (MRO) was launched on August the 12th, 2005 from the Kennedy Space Centre in Florida. MRO transmits on DSN channel 32 which is 8439.444444 MHz, by the time that reaches Earth, due to Doppler the frequency has changed significantly. MRO has a 3 meter diameter dish antenna driven by a 100 Watt TWTA to transmit signals to Earth, this means that the signal coming in our direction is of the order of 4.2 mega watts of RF, loud by any standards.
Update 29 May 2017 A couple of video recordings of X-Band reception from MRO:
Update 23 December 2007 MRO is an easy copy despite massive doppler:
Update 24 August 2006 16:24GMT MRO is a reasonable signal !! see FFT below. Current QRG 8439.347 @ 16:24z
Update 18 August 2006 14:29GMT MRO is very weak!! see FFT below. Current QRG 8439.3112 @ 14:34z
Update from 14 March 2006 The MRO went into orbit around Mars on the evening of the 10th of March 2006, and as expected, amateur observers were watching the signal on 8.4GHz and listening to the NASA tv feed to see what was happening.
The picture above shows the MRO carrier as NASA switched from the MRO's HGA to the omni-directional LGA, of course larger DSN antennas could receive the signal, but it was too weak for amateur observers.
The picture above shows MRO emerging from behind Mars, and NASA switching communications back to the HGA - notice the doppler is now moving in the opposite direction at a much slower rate. At the time of signal reacquisition the frequency was 8438.952364 MHz.
This picture shows the MRO signal received when Mars was 137264250 miles from Earth, with the MRO spacecraft orbiting - as can be seen the signal is massive, and easy to copy with a 1.8m dish. The vertical line is a leak at the IF centre frequency. The receive frequency was around 8438.957522 MHz.
This is the dish being used to track Mars and the MRO Orbiter - its an old 1.8m 'NEC' antenna with a home-made adapter plate to allow it to be used with the AZ/EL tripod. On the table is the dual band down converter and associated 24v PSU.
Update 7-January-2006 Received MRO again this evening, signals were about 4 to 5dB above the noise, and copyable in SSB. The MRO was 69593573 miles away which is 25 million miles further away than when I first copied a signal from it!
Update 20-December-2005 From this reception test, two recordings have been made - you can now easily hear the carrier from the MRO. As above, use your favourite FFT program to process the sound files. At the time the wave files were recorded, the MRO spacecraft was more than 53258740 miles away. During the reception, what looked like 2 sidebands, 3.24KHz +- the carrier were detected. James Miller, G3RUH has kindly been calculating CNR's for the recordings - tonight's is 24.7 dB-Hz, which is a staggering 14dB improvement over the 'old' LNA. The author wishes to thank James, G3RUH for his continuing support and help with these receive tests.
MRO audio recording 1:
MRO audio recording 2:
Here are copies of the articles that appeared on the Internet following the slash-dotting of the MRO site.
Monitoring Times - April 2006
RSGB WWW Site
RSGB WWW Site
RSGB WWW Site