Date   : Wed, 01 Sep 2004 07:13:44 +0100
From   : "Charles Blackburn" <charlesb@...>
Subject: Re: Astrid satellite receiver

Sounds abouth right. the web page for the amateur radio birds is @ amsat
http://www.amsat.org/amsat-new/index.php



on there you will find links to the current birds, although I beleive that
oscar-11 may still be heard. this page http://www.users.zetnet.co.uk/clivew/
actually has some bbc basic stuff in it even a library of s/w. now if G3CWV
andy is part of the list it might be interesting if he aint, maye we can get
a hold of him to get him to send sum1 the disks for preservation.

----- Original Message ----- 

From: "Pete Turnbull" <pete@...>
To: "Jules Richardson" <julesrichardsonuk@...>;
<bbc-micro@...>
Sent: Tuesday, August 31, 2004 11:53 PM
Subject: Re: [BBC-Micro] Astrid satellite receiver


> On Aug 31 2004,  8:23, Jules Richardson wrote:
> > On Tue, 2004-08-31 at 00:21, Pete Turnbull wrote:
> > > I had a magazine reprint and possibly some other info about it.
>  I'm
> > > sure that had information about antennae.  I'll have a look.
>
> > Well some info I dug up on the web implied that it was designed to
> work
> > with both UoSAT1 and UoSAT2 - UoSAT1 died after only a couple of
> years
> > by the sounds of it due to the batteries used, but UoSAT2 was still
> > going in 2002 according to a Usenet post I found.
> >
> > There's a switch on the front labelled data 1 and data 2 - maybe
> that's
> > to flick between the different satellites (or something else entirely
> > :-)
>
> OK, I found the documents, such as they are.  ASTRID was designed by
> one Stephen Webb, who ran a company called M.M.Microwave (and
> M.M.Technology and others: their real business was making military
> radar and missile components) in Kirkbymoorside, not so very far from
> here -- but they're not around now (or at least not in the same place).
>
> ASTRID stands for Automatic Satellite Telemetry Receiver and
> Information Decoder, and cost £129.57 + VAT (£149).  The system
> consisted of the receiver box, aerial with standard TV-type downlead
> and coax plug, mains PSU (nominal 12V-14V DC), connecting leads for a
> mono tape recorder and computer serial port, software and handbook.
>
> It's designed to receive ASCII digital telemetry data from the UoSAT1
> and UoSAT2 satellites on 145.825MHz; bandwidth is 12kHz.  It decodes
> the signal into tones and these can be recorded on tape or passed back
> into the ASTRID circuitry and decoded into a serial data stream at 1200
> baud (7E1), as well as listend to on the audio output (8-ohm speaker).
>  It's reputed to be unusually sensitive and the antenna doesn't need to
> be steered.  The antenna and cable it comes with is 75ohm, but it says
> it can be used with 50ohm ones.
>
> Since the UoSAT?s are polar orbiting (UoSAT2 is OSCAR-11), you'd only
> pick up a signal (with the antenna pointing more or less straight up)
> when a satellite was in range; when ASTRID detects a signal it switches
> on the tape recorder.  Everything else is automatic.
>
> If the tape recorder is connected, it will record the data; if there
> are no plugs in the MIC and EAR sockets then the data will be decoded
> and come out the serial port (which is actually a TTL port, not RS232,
> on most versions).  Normally you'd record the signal using the MIC
> socket and then play it back into the EAR socket later, to get it
> decoded, using the pause control on the tape as required.  If it's
> receiving a live signal while you're playing back a recording, it puts
> the live signal out the MIC socket while decoding the recorded one
> you're playing back into the EAR socket.
>
> There's some info on UoSAT2 on the University of Surrey's pages, and
> pages linked to from there.
>
> www.ee.surrey.ac.uk/SSC/CSER/UOSAT/missions/uosat2.html
> http://www.users.zetnet.co.uk/clivew/oscar11.htm>
> http://science.nasa.gov/Realtime/JTrack/3D/JTrack3D.html
>
> If you remind me of your address, I'll post you photocopies of the
> meager info I have.
>
> -- 
> Pete Peter Turnbull
> Network Manager
> University of York
>
>
>


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.744 / Virus Database: 496 - Release Date: 26/08/2004