[net.micro.atari8] using Atari 800 to generate TV graphics

ccrbrian@ucdavis.UUCP (Brian Reilly) (09/04/86)

Hi - I have a friend who works for a television station which would
like to use some computer graphics in between their shows.  Since it is
a low budget operation, they are using an Atari 800. (very low budget
obviously)  However, according to my friend, the 800 does not put out
enough volts to generate a good image.  He thinks that it can be
modified to do this.  They are writing the screens to a VCR, and I
don't know too much more about it.  Does anyone have experience doing
this or any suggestions?

Thanks

- brian reilly
{lll-crg,ucbvax}!ucdavis!vega!ccrbrian
con.reilly@su-gsb-how.arpa
btreilly@ucdavis.bitnet

andy@batcomputer.TN.CORNELL.EDU (Andy Pfiffer) (09/07/86)

In article <506@ucdavis.UUCP> ccrbrian@ucdavis.UUCP (Brian Reilly) writes:
>Hi - I have a friend who works for a television station which would
>like to use some computer graphics in between their shows.

Back when I was the chief engineer of a college television station, we used
a 400 as a VERY crude character generator (we couldn't afford a real one).
We later used an 800XL (much better keyboard) with a 1050 drive and some
more sophisticated software (storing title screens on disk).

Its true that these machines don't generate "true" NTSC compatible video.
The signal is more than adequate for driving a monitor or VCR, but that is
about the limit.  The colorburst is about 1/2 the required frequency, and
triangular at that.  The overall signal is too low to properly drive most
equipment.  We did end up dedicating a distribution amplifier to it...

However, it was "close enough for government work" -- particularly if used
with inferior equipment with less stringent tolerances (surprisingly...).
We eventually relegated it to making leaders and titles for tapes, and as
a message board when no other programming was scheduled.  It just couldn't
properly sync our studio cameras and switcher.

I expect that a low quality time base corrector combined with a good
amplifier could end up improving the signal significantly.

I don't know if they are still using the setup (its been 3+ years since I
was at the station).

	Andy Pfiffer