WLAN guru detects and receives NASA’s Mars Reconnaissance Orbiter – Slashdot

By unwire, December 22, 2005


Richard L. James writes "As reported on the Mars-net email list Flight Refuelling Amateur Radio Society’s resident satcom + WLAN guru Paul J. Marsh (M0EYT) has managed to detect and receive NASA’s Mars Reconnaissance Orbiter on X band at a staggering range of 45 million miles from Earth using a home made receiver setup and a RFspace SDR-14 software radio." 

Paul’s project page:

The goal of receiving an inter planetary space probe has finally been realised 😉 – the primary objective of building a working Venus Express receiver culminated with the reception of the TT&C signal at 8.4GHz today the 5th of December 2005 at 15:50UTC. The secondary objective is to improve the receiver and listen for and hear the Mars Express signal also at 8.4GHz. The inspiration for this project came from the demonstration of Mars and Venus Express reception at a UK Microwave meeting held in November, just three weeks ago.

RFspace SDR-14 is a 14-bit software defined radio receiver:

The Mars Global Survey Relay Test:

In a message forwarded to me:

A goal similar to this was achieved during the MGS cruise to Mars in 1996.  See,
for example:




so forth (google ‘MGS "Amateur Radio" 1996′ or similar).

John Callas
coordinated an amateur radio effort on behalf of the MGS team at JPL.  Several
dozen participated in meetings at JPL held for the purpose of introducing hams
to the techniques involved and several dozen (some of the same people and some
others, worldwide) participated successfully in the listening tests.  For
amateurs already equipped for 70 cm moonbounce, this was fairly
straightforward.  Others set up special stations specifically for the MGS test. 
Stanford University led with a semi-official team:


contact between amateurs equipped at this level will be possible between
stations on earth and Mars, once we get someone to Mars.

Amateurs were
also active in the 60s and early 70s listening direct to the astronauts on the
moon (S-Band) and places in between.  Although the moon is only a quarter
million miles away, it counts as "deep space" for these purposes.


  1. ClickRich says:

    Readers of this post based in the UK might like to know of an upcoming opportunity to hear Paul’s story first hand.

    “45 Million Miles from Earth”

    In this, the first of the 2006 programme of IEE Lectures in Bournemouth, Radio Ham Paul Marsh describes how he built and used a home made receiver to sucessfully recieve signals from NASA’s Mars Reconnaissance Orbiter transmitting in X-band at a staggering range of 45 million miles from Earth. As NASA’s New Horizons’ mission to Pluto gets underway, for how long can amateurs keep pace with the space race?

    Speaker: Paul Marsh, IBM and keen Radio Ham
    Venue: Allsebrook Lecture Theatre, Bournemouth University
    Date and Time: Tea/Coffee from 6:30pm. Presentation from 7pm, Thursday 2nd March 2006
    For further details, go to http://www.iee.org/events/event/2A684783-F3FB-1A06-8A2032FA6B60B44D&i=1

  2. ClickRich says:

    UPDATE… Paul will be bringing the hardware to the presentation with him.