Thanks Graham,
I have to my knowledge, been searching the entire Internet looking for information about Prospero, and have no idea what else I can try. The audio file of the German radio amateur do not help me much further and therefore have no idea what to expect when Prospero finally transmits something.
I tryed all kinds of modulations and scanned the band - and + 500 KHz with 137.560 MHz as center freq.
In AM I receive what seems the 57k6 transmittions from ORBCOMM.
I hope the Team that is trying to re-contact prospero have more luck.
Lets all keep in contact and share our findings.
73 Jan PE0SAT
On Tue, October 25, 2011 21:59, [email protected] wrote:
Hi Jan,
FWIW - my reading of the slightly old fashioned English text, is that the command transmitter is on a frequency around 148MHz, that it uses "two tones" and that the on board receiver and decoder is capable of understanding 35 commands. As it happens, the ground segment for the Orbcomm constellation also uses similar frequencies and "tones", so maybe you actually heard a ground based device nearby to you, doing its uplinking?
73
Graham G3VZV
-----Original Message----- From: PE0SAT Sent: Tuesday, October 25, 2011 3:31 PM To: [email protected] Cc: [email protected] Subject: [amsat-bb] Re: [Prospero Commanded Pass Today]
Hi Roger,
The information about a second freq. came from the following document:
http://www.pe0sat.vgnet.nl/downloads/Prospero-Satellite.pdf written by H.J.H. Sketch.
Have a look at part 3.1
Here a part of that paragraph
"The v.h.f. system is conventional using twin transmitters, each with an output of 350mW at approximately 136 MHz, and a twin tone digital command system operating at about 148 MHz which handles the 35 separate commands"
Second graph I placed last night looks like a twin tone, and is received around 148.010 MHz.
With regards,
Jan - PE0SAT
On Tue, October 25, 2011 15:43, Roger Duthie wrote:
I don't think there is a 148MHz transmitter, though Prospero's uplink is 148.25MHz.
Also, after looking at your page I think I should say that we think that the Coast BBC transmission was almost certainly an Orbcomm transmission. The Prospero downlink frequency was reassigned to Orbcomm.
Which sound file are you talking about? There are what claims to be original audio files here: http://www.dd1us.de/spacesounds%204.html (you need to find Prospero further down the page).
- Roger
PE0SAT wrote:
Hi Roger,
I have updated http://www.pe0sat.vgnet.nl/satellite/sat-history/prospero/ with my latest images and recordings. It is possible to get the complete audio file. Send me a direct email and we can arrange something.
I had read that there is a 148.000 MHz transmitter on board prospero, and I listend to that frquentie during the pass from 15:55 UTC. Maybe it is interesting what is happening on that transmitter.
How do things go on your site regarding PROSPERO? any news?
73 Jan PE0SAT
On Mon, October 24, 2011 13:01, Roger Duthie wrote:
AMSAT community -
The Mullard team intend to attempt commanding to Prospero during the
following pass:
(entries are: date; mag; start time; el; az; max el time; max el; az;
end time; end el; end az)
24 Oct http://www.heavens-above.com/Gtrack.aspx?Session=kebgfdalljnnahdmapeidbkh&satid=5580&date=40840.6673023843 7.7 16:54:17 10 SSW 17:00:54 58 WNW 17:08:40 10 N
Any listening on the downlink, and feedback on your observations, would
be most appreciated.
We may also try the later pass:
24 Oct http://www.heavens-above.com/Gtrack.aspx?Session=kebgfdalljnnahdmapeidbkh&satid=5580&date=40840.7412698495 9.3 18:42:56 10 W 18:47:25 17 NW 18:52:14 10 N
**** TIMES ARE IN BST (ie., UTC + 1) ****
- Roger
PS., I hope the copy-paste from heavens-above works.