[Coco] Monitor Adapters was >Re: *COOL* Look what I found! (VideoMod for CoCo2)

John Eric jet.pack at ymail.com
Thu Jan 22 17:05:56 EST 2009


the 6847 outputs difference signals (theta a and b). luminance and r-y, through properly weighted comparator will give red, likewise, using the same "resistor" weighting of a second comparator with lumina and b-y will give blue. Then, red and blue into another comparator, which then feeds another comparator with it's output along with lumina gives green. i've finished the design on paper and when i get the parts in to test it I will post either:failure or success, or something in between :) -jeric




________________________________
From: Mike Pepe <lamune at doki-doki.net>
To: CoCoList for Color Computer Enthusiasts <coco at maltedmedia.com>
Sent: Sunday, January 11, 2009 10:50:52 PM
Subject: Re: [Coco] Monitor Adapters was >Re: *COOL* Look what I found! (VideoMod for CoCo2)

Interesting. I wonder how one derives the RGB signals from the luma,
phase A and phase B signals that the 6847 spits out.

> -----Original Message-----
> From: coco-bounces at maltedmedia.com [mailto:coco-
> bounces at maltedmedia.com] On Behalf Of Torsten Dittel
> Sent: Sunday, January 11, 2009 1:29 AM
> To: coco at maltedmedia.com
> Subject: Re: [Coco] Monitor Adapters was >Re: *COOL* Look what I
found!
> (VideoMod for CoCo2)
> 
> I've got several RGB CoCo 1, 1a, 2, 2b and MC-10 with RGB output in my
> collection. These were made for France (Europe) only. They even
produce
> the correct control voltages to select RGB via SCART. The place and
> space on the main PCB, where the HF modualtor would normally reside,
> has
> been used for the corresponding circuits. However, these are all 50Hz
> PAL models (not NTSC) and have a french keyboard layout (not QWERTY).
> 
> Some pictures of the CoCo 2B board and RGB video sections:
> 
> http://dittel.org/CoCo/pcb_compl1.jpg
> http://dittel.org/CoCo/pcb_compl2.jpg
> http://dittel.org/CoCo/pcb_detail1.jpg
> http://dittel.org/CoCo/pcb_detail2.jpg
> 
> MC-10:
> 
> http://dittel.org/MC-10/PICT0001.JPG
> http://dittel.org/MC-10/PICT0002.JPG
> http://dittel.org/MC-10/PICT0003.JPG
> http://dittel.org/MC-10/PICT0004.JPG
> 
> Regards, Torsten
> 
> 
> --
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco


--
Coco mailing list
Coco at maltedmedia.com
http://five.pairlist.net/mailman/listinfo/coco



      



More information about the Coco mailing list