[amsat-bb] Fw: Fw: AMSAT-DL Hears Mars Science Laboratory X-Band Downlink

[i8cvs]

----- Original Message -----
From: "James R Miller" <g3ruh at jrmiller.demon.co.uk>
To: <domenico.i8cvs at tin.it>
Cc: <peter.guelzow at kourou.de>
Sent: Monday, November 28, 2011 1:57 AM
Subject: Re: Fw: [amsat-bb] AMSAT-DL Hears Mars Science Laboratory X-Band
Downlink

> Dear Domenico,
>
> > I was really impressed reading your report about receiving the
> > MSL beacon of MSL on the following page:
>
> Thank you!
>
> It is not difficult; we receive lots of the NASA spacecraft all the time.
> Stereo-A/B every day, and when they have gone LOS, we (I) check Grail-A
> and Grail-B and also Juno.  When Juno was new, the signal was huge, and
> enabled the beam shape to be determined with greater depth than before.
>
> Grail-A/B have very high performance Ultra Stable Oscillators (USO) and
> they are free running.  A daily check allows us to check independently
> that our own station oscillators remain in accurately lock.
>
> Reception of MSL required adding its trajectory data to the spacecraft
> database, and the frequency to the radio control computer.  Provided the
> given frequency is with +/- 40 kHz of the actual frequency, we can lock
> onto it in 1 sec via an FFT acquisition process.  As it happens, the
> actual frequency was within 8 kHz of the DSN channel centre, so finding it
> was immediate.
>
> The station computers can be remotely accessed from home to do software
> maintenance jobs.  Hardware requires people to go to the site, of course.
> Remote software management is probably the most important part of this
> story.
>
> Article about telescope systems:
>  http://www.amsat.org/amsat/articles/g3ruh/126.html
>
> Article about Stereo A/B reception:
>  http://www.amsat.org/amsat/articles/g3ruh/127.html
>
> Hoping you are in good health.  Wish I was in Italy for the winter!
>
> 73 de James G3RUH
>
> --
> ==========================================================================
>     James R Miller      WWW/PGP:     http://www.jrmiller.demon.co.uk/
>   Cambridge, England   Stardate:        2011 Nov 28 [Mon] 0053 utc
> ==========================================================================

HI Peter, DB2OS and James, G3RUH

I was really impressed reading your report about receiving the
MSL beacon of MSL on the following page:

http://tinyurl.com/7t5xjwk

Congrats to you Peter and James , I am sure that in the future
AMSAT-DL will be able to launch P3-E and P5-A

Thanks also to JoAnne K9JKM for providing us with the above
information.

73" de

i8CVS Domenico