Stupid Amiga Tricks

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Thu Jun 10 18:05:55 2004

>
>
> Why does everything have to be so difficult?
>
> I'm trying to set up an Amiga 500 for tonight's Computer History Museum
> event. It's got a DB-23 RGB output and a Mono out. I've got an Amiga

What is the correct name for the 23 pin D connector? It's slightly
smaller than a B shell. I've seen it called the DG23 (and DF19 for the 19
pin connector on the Atari ST DMA port), but I don't know how official
they are.

> 1080 high resolution color monitor. It's got a Video and Chroma input,
> plus a DA-9 RGB input. I've got an Amiga RF Modulator that plugs into
> the DB-23 on the back of the Amiga and has a composite Video and Audio out
> (and an RF out). Then I have several video cables. One is a DB-25 to a
> DIN. Another is a DIN to three RCA leads. And then there's the DIN to

How many pins on the DIN plugs?

> DA-9. At least one of these might be for the Atari 520ST (which I also
> need to set up).
>
> None of this connects up in a way which gives me colour on the display.

_NOW_ do you know why I like to have schemaitcs to everything :-). If I
had more specs on what the signals actually were (RGB can mean just about
anything), it would be easy to make up the right cable. In fact I could
probably do it in less time than it takes to send this message.

IIRC, the 520 modulator has a composite colour output (luminance and
chromanace in the same signal, like a baseband TV signal). Commodore
monitors often had separate luma and chroma inputs (a bit like the
S-video connector, but on separate RCA phono sockets). If you connect the
5230's output to the lumanace ('video') socket on a commodore monitor,
you get a monochrome picture.

In any case, assuming the RGB signals are compatible (I assume the Amiaga
outpus analogue RGB at TV rates), you'd get a better picture using them.
It should just be a matter of matching up the signals on the 2 connectors.

I've long since given up trying to find the right cable for things like
this. To be honest it's quicker to make one. And then I hopefully keep it
with whatever device it goes with...

-tony
Received on Thu Jun 10 2004 - 18:05:55 BST