Re: Question for other Highway converter owners

["Michael J. Mahon" <mjmahon@aol.com>]

Steven Hirsch wrote:
> Steven Hirsch wrote:
>
> > Steven Hirsch wrote:
> >
> > > This evening, I'm planning to rewire the SCART cable so the IIGS 
> > > composite sync goes to the SCART sync-in instead of composite video.  
> > > This will likely not help the banding, but may mitigate some of the 
> > > flashing and flickering (which really does look a sync problem).
> >
> >
> > Alas, turns out that IIGS sync _is_ connected to the only place where 
> > it can go on the SCART connector; composite video in.
>
>
> Followup on my travails with the Highway 100 converter:
>
> By default, Roger Johnstone's IIgs --> SCART cable applies composite 
> sync to the composite video input on the converter.  MdntTrain told me 
> this yielded the best results on his unit, so I never really mucked 
> around with it.  Today I discovered that I'm better off applying the 
> IIgs composite video signal to that pin!  It seems to have solved the 
> worst of the banding problems and the picture now looks quite good.
>
> The question is: Why does this behave so differently between the two 
> converters?  At any rate, life is now good and I can heartily recommend 
> the Highway converter to other IIgs owners with the proviso that you may 
> need to do some experimentation with the wiring.

This could be the result of a greater sensitivity to sync levels in
your card, and that could result from any number of small changes on
the Highway converter.

A simple experiment would be to put a 100-Ohm pot between the IIgs sync
signal and the sync-in pin.  If the problem is fixed by reducing the
level of the sync, that would confirm the hypothesis.

I'm glad you got it working!

-michael

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