🚀 go-pugleaf

In article <880204-065400-4005@Xerox> brantly.henr@XEROX.COM writes:
>>The $100 plus price tag for a RGB to composite cable seems a little steep.
>>Elektor magazine (it from the UK) published a circuit to do this called
>>Atari ST to SCART adaptor in early 87 (march I think).  SCART is an
>>analog RGB interface with composite sync - I think this should do what you
>>need.  Parts cost is under $20.00
>
>-------------
>
>The Atari ST to SCART adaptor sounds interesting, but would it provide BOTH rf &
Ther is a great difference in the technique: 

The Euro-AV (SCART) includes extra lines for almost evey signal a TV can
handle: one for each:red, green, blue, horizontal-sync, vertical-sync,
composite-sync, composite video and so on.

Composite video (or FBAS in Germany) contains the complete picture on a
single line: it is the signal the modulator will put on top of the RF
and make it look like coming from an antenna.
The ST has outputs for RGB and composite-sync (sync not video!). The
RGB-compVid-Converter will have to put this information on a sigle line,
whitch is a tricky task. But the Motorola MC1377-chip (you will find one
opening your video camera or Amiga) solves this problem. Here in Germany
a Magazine (c't) published a board containig this chip and a little more
(resistors, capacitators) to get composite video.

A simple solution ist mixing RGB and compSync together by a resistor
network: connect 300 Ohms to each, red green and blue, 50 Ohms to
composite sync and solder the open ends together; what you will get is
an grey-scale video signal of the medium or low resolution; I am using
this to display all the colour-games on a green monitor. Not the
solution but cheap...
hase
-- 
Hartmut Semken, Berlin (West) (*east of West-Germany :-)
hase@netmbx.UUCP
answer: 42 question: under development. Stay tuned.