New Horizon 4.78 Billion Kilometer data links ... information that helps us understand how this works

[Ethan Waldo]

Oops, sorry for double-posting the Horizon's link Ralph.  I didn't scroll down far enough in the thread.

________________________________
From: Tacos <tacos-bounces+ewaldo=healthetechs.com at amrad.org> on behalf of Ethan Waldo <ewaldo at healthetechs.com>
Sent: Thursday, July 23, 2015 1:10 AM
To: AMRAD
Subject: Re: New Horizon 4.78 Billion Kilometer data links ... information that helps us understand how this works


I read somewhere that Voyager's signal is quite easy to pick up compared to many radio astronomical observations.  https://www.nrao.edu/pr/2013/voyager/ provides a great visual approximation of the "small lightbulb" that is Voyager's radio signal.


To understand how they expanded the DSN several times to accommodate Voyager http://descanso.jpl.nasa.gov/monograph/series5_chapter.html<http://descanso.jpl.nasa.gov/monograph/series5/Descanso_Mono5_full.pdf> and "Voyager Telecommunications" under http://descanso.jpl.nasa.gov/monograph/series13_chapter.html are great reads.


http://www.boulder.swri.edu/%7Etcase/NH%20RF%20Telecom%20Sys%20ID1369%20FINAL_Deboy.pdf<http://www.boulder.swri.edu/~tcase/NH%20RF%20Telecom%20Sys%20ID1369%20FINAL_Deboy.pdf> is a fantastic paper about the New Horizons telecommunications system authored by Johns Hopkins APL.  It has 2x12W TWTAs with a 42 dBic 2.1m HGA.

________________________________
From: Tacos <tacos-bounces+ewaldo=healthetechs.com at amrad.org> on behalf of Phil via Tacos <tacos at amrad.org>
Sent: Tuesday, July 21, 2015 7:24 PM
To: Tacos AMRAD
Subject: Re: New Horizon 4.78 Billion Kilometer data links ... information that helps us understand how this works

I believe that the New Horizons transmitter puts out about 28 W from five billion kilometres away. Voyagers 1 and 2 put out less from about 20 billion kilometres away. Ever wondered what it would be like to hear somebody whispering in LA while you listen in DC? This is harder.

Phil M1GWZ



On 21 Jul 2015, at 22:09, Alberto di Bene wrote:

On 7/21/2015 7:09 PM, Ralph Wallio, W0RPK wrote:

Interesting real-time network status is available via https://eyes.nasa.gov/dsn/dsn.html.

There is something that I fail to understand on that site....
Selecting as antenna Madrid 54, sending and receiving from MMS3, it is possible to see what follows :

<jdicgibg.png>

Now, a power received of 3.81 x 10^-55 kW, translates (unless I made an error) to about -484 dBm....
I don't know what the gain of that antenna is, but -484 dBm seem unreasonable....

73  Alberto  i2PHD



_______________________________________________
Tacos mailing list
Tacos at amrad.org<mailto:Tacos at amrad.org>
https://lists.amrad.org/mailman/listinfo/tacos

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.amrad.org/pipermail/tacos/attachments/20150723/0ad3b976/attachment-0001.html>