Satellite stuff (Was: Re: BBC printer port (ever used for anything

From: Jules Richardson <julesrichardsonuk_at_yahoo.co.uk>
Date: Mon Sep 20 17:18:17 2004

On Mon, 2004-09-20 at 05:40 +0100, Tony Duell wrote:
> > > Right. The Maplin one (Published in the Maplin Magazine) used only the
> > > user port IIRC.
> >
> > I've got another one (decoder only) which looks very Maplin-ey. That one
> > just has a pair of SPDT switches on the front along with a meter marked
> > 0-10, whilst at the back there's just power, and a pair of DIN sockets -
>
> I will ahve to dig out the Maplin docs. IIRC that one had a 20 pin ribbon
> cable which connected to a Beeb user port (or to a input port card for an
> Amstrad CPC...)

Yes, I'm not quite sure what I have with this bit of kit. UoSAT offered
all sorts of telemetry though, so presumably this thing's designed to
filter out some specific data...

> The DIN sockets do sound Maplin-like, but I thought they were on the
> receiver. One linked to the decoder, the other to a tape recorder (you
> recorded the analogue signals from the satellite, then played them back
> into the decoder later on).

Yep, the Astrid receiver I have is exactly like that - there's some TTL
in it which is used to drive the computer's serial port, plus sockets
for hook-up to a tape unit for recording.

That's what makes this other box that I have odd - the Astrid receiver
includes the necessary logic for interfacing to the CPU, and this other
box doesn't seem to have enough I/O lines to be for complex data
aquisition (such as imagery) - but I can't imagine what it's doing that
couldn't have just been done in software on the host computer.

I'm sure all will become clear when I get the time to trace the
schematic out!

> Maplin sold PCBs (with silk-screen overlay) and printed case panels IIRC.
> This could be a homebrew copy, or it might (more likely) be another
> magazine project.

the board's semi-professional, in that it looks to be low-volume, but
the lettering on it is all nicely done as are the marking giving
component locations etc. (plus I notice that the front and rear metal
panels are properly earthed, and the soldering's all good). Smells more
like something built-to-order in a small workshop (as was typical for
all sorts during the home computer boom I suppose!)

> > > I do have a 'real' weather satellite receiver system. It came from
> > > ic.ac.uk, and the bit I really wanted (and got) were the 3 I2S image
>
> [...]
>
> > I'd forgotten you had that. Do you have sufficient software to make it
> > do something as a complete system if a suitable VAX were found, or has
>
> Alas not. I got the I2S driver tape I think, but nothing more :-(

That's a shame. There must be a lot of big and complex systems that
would make interesting museum displays which have gone the same way due
to lack of software preservation :-(

cheers,

Jules
Received on Mon Sep 20 2004 - 17:18:17 BST