[BBC-Micro] CEEFAX short story contest

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Tue Sep 21 20:26:43 2004

>
> you could in fact quite legally broadcast a teletext signal from a small
> transmitter if you are capable of building one, you MUST be careful however

Some of the better TV test generators now include a few teletext pages --
there was a review of one in this month's 'Television' magazine which
costs a bit over 100 quit and which will output 4 teletext pages along
with the normal 'test card' video image.

It can't be that hard to make a teletext generator, actually. When I get
my ACW working, and the Morley teletext decoder hooked up to it, I might
have a go at making a generator.

> to make sure that you get no spurious emissions and also dont use an aerial
> but a coax feeder between the tx and the tuner. (IE link it up exactly as
> you would a TV).

I wonder if the stnadard video modulators would have enough video
bandwidth for this. I know of at least one device which used such a
modulator without an audio input, and generated the 6MHz sound
intercarrier with a separate oscillator, mixed it with the video and fed
it into the modulator. It worked. So you might get away with feeding in
teletext data too.

-tony
Received on Tue Sep 21 2004 - 20:26:43 BST