BBC printer port (ever used for anything else?)

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Sun Sep 19 15:28:26 2004

> > So has anyone ever heard of the Beeb printer port being used for
> > something other than a parallel printer?
>
> The docs for the Timestep weather satellite decoder which I have in
> front of me say that the unit uses the printer port. It appears to feed

Right. The Maplin one (Published in the Maplin Magazine) used only the
user port IIRC.

> the 2 or 4Hz clock output from the decoder into the printer port; the
> user port is tied up handling the digital representation of the analogue
> satellite signal.
>
> Incidentally, the docs actually contain full schematics (it's not a

The Maplin Mags contains schematics for the receiver and decoder. Alas
the receiver PCB was supplied ready-build so there's no alighment info
:-(. Oh well...

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
processor/display units (really interesting graphics displays for
PDP11/VAXen), complete with schematics, etc. I didn't get the computer (a
VAX), but I did get the indoor bits of the receiver -- everything from
the 137MHz 1st IF onwards, and the first local oscillator at a couple of
GHz. I didn;t get the dish or first mizer. This part is clearly home-made
(well made, but it's a 1-off -- the RF bits are built by 'dead bugging'
on a copper-clad-board ground plane in metal screening boxes, the digital
bit is on stripboard..

I am told this machine was used to receive the weather satellite images
for the BBC weather forcasts at one point....

-tony
Received on Sun Sep 19 2004 - 15:28:26 BST