[BBC-Micro] Monitors

[Anders Carlsson]

Mark McDougall wrote:

> I'm looking to hook it up to a 1084s. My choices are to clip the RGB and
> feed the analogue input, or feed the digital input. But I still have to
> generate H/V sync from the sync output of the BBC... anyone already doing
> this out of interest?

I'm using my BBC and Electron computers with a 1084S monitor. At first I 
tried the digital TTL input, but it rendered a picture with only red text, 
slowly fadining away. It could be my monitor that is partly broken. Instead 
I wired up some resistors acting like voltage dividers and am using the 
analogue RGB input. It works fine, although there are different theories how 
those voltage dividers should be properly wired as regarding impedance 
bouncing around in the cable or something.

I remember being stumped on the H/V vs C sync too. From studying different 
1084 models, which internally seem quite similar, I came to the conclusion 
that it is enough to feed horizontal (I believe) sync. I may be wrong on 
this, and should inspect my cable once at home.

Currently I'm planning to build my own BBC to SCART cable, using similar 
technologies as I used before. I know there are some diagrams on the 
Internet for a possible design, and sound counter arguments. (what is the 
Internet and email for, if not complaining on other people's ways of doing 
things?)

Regards

-- 
Anders Carlsson