[Coco] Will this build-your-own s-video board work for CoCo 3?

gene heskett gheskett at wdtv.com
Wed Mar 9 00:06:01 EST 2011

On Tuesday, March 08, 2011 11:46:43 PM Blake Patterson did opine:

> But, doesn't the CoCo 3 wire straight into a 1084? From what I've read
> it just works on that screen. Wouldn't that mean it's the same signal
> type of the Amiga?
> Thanks.

Sort of.  By way of explanation, the 1084 cable has a sync combiner chip 
cast into the db23 plug that plugs into the amiga, in order to combine the 
H & V syncs and correct the polarity.  That chip is the single most common 
failure when connecting things up and the power cables 3rd pin static 
ground is missing or defeated by a drop cord.

The 1084 is essentially a stripped Magnavox 8CM515, which had enough input 
options that I was able to use one with a fairly straight through wired 8 
pin din connector until the HOT (horizontal output transformer) went up in 
smoke from old age, several years ago.  Parts, like the HOT,were dropped by 
NAP just as soon as the feds with their 5 year law would let them.  I tried 
to buy a HOT about a month after the manufacture date for a monitor at the 
tv station, and got told by North American Phillips (parent of Magnavox) to 
buy a new one.  My reply was that I would, what model replaces it?  I 
parted with some surplus mind when they said they no longer made a 
comparable monitor.  My own 25" Maggy tv upchucked 3 weeks later, and it 
sure wasn't another Magnavox that replaced it.

> (I can't go straight to a 1084 with a properly wired simple cable,
> then?)
See above, its a little more complex.  One could google for building it, 
ISTR I did that almost before there was a google and found a drawing on it. 
1998 maybe?
> bp
> On Tue, Mar 8, 2011 at 10:29 PM, Steve Bjork <6809er at srbsoftware.com> 
> > Not without a circuit to convert H & V syncs of the CoCo 3 to one sync
> > like on the Amiga.
> > Better to stay with a RGB �converter that been designed for the CoCo
> > 3.
> > 
> > On 3/8/2011 6:25 PM, Blake Patterson wrote:
> >> I recently acquired a CoCo 3 and want s-video (or component) output.
> >> I saw this a while ago: http://www.youtube.com/watch?v=LDP8cvIXtFY
> >> Will the mentioned Neobitz board work if I wire the Coco 3 to it?
> >> http://neobitz.com/Pages/Mods/SystemMods.aspx
> >> Thanks.
> >> bp
> > 
> > --
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> > Coco at maltedmedia.com
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Cheers, Gene
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 soap, ballot, jury, and ammo. Please use in that order."
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