Re: Asteroids X axis problem

>Does the test pattern similarly degernate into a line at the edges
>unelss the size is reduced?

Yeah, it kind of mashes up the diagonals as they hit the far left and
right edges.

>Are your +15V & -15V good?

Yup, no problems there.

Thanks,
Phil

>--- On Thu, 3/11/10, arcaderelics@irongiant.org.uk
><arcaderelics@irongiant.org.uk> wrote:
>
> > From: arcaderelics@irongiant.org.uk <arcaderelics@irongiant.org.uk>
> > Subject: Re: VECTOR: Asteroids X axis problem
> > To: vectorlist@vectorlist.org
> > Date: Thursday, March 11, 2010, 1:53 PM
> >
> > > > I can't unfortunately see any faults when I
> > 'scope out the signals.
> > > When you "scope out" which signals? If the output
> > (X&Y) looks good, then you're looking at a monitor
> > problem.
> > >
> > > Either way, it sounds like a problem in one of the
> > analog sections (monitor or board), as in a signal
> > clipping.
> >
> > The 4016 has been replaced as it was faulty (total screen
> > collapse in the X axis) so perhaps the TL081 or TL082 ?
> >
> > Perhaps even the AD561 ?
> >
> > > If you make the picture smaller, does the "vertical
> > line" unfold in an object?
> >
> > Sorry, Forgot to mention - the problem goes away if the
> > picture is reduced to 'small to moderate' size in the X axis
> > - if it's between moderate to large then the fault occurs.
> >
> > > Do you have a picture?
> >
> > Afraid not, not much to see really though, just a vertical
> > line the height of the object as it passes through the edge
> > of the screen (the object is still drawn okay though).
> >
> >
> > Thanks,
> > Phil
> >
> >
> >
> > >
> > > -Mark
> > >
> > >
> > >
> > > Just been fixing up my first Asteroids board for ages
> > - multiple problems, all now fixed ......... except for
> > one.
> > >
> > > Whenever an object gets to the far left or right edges
> > of the display it's still drawn okay BUT as the object
> > passes through the edge it makes a vertical line at that
> > edge where the object is passing through - the line is same
> > 'height' as the object too.
> > >
> > > Now I've seen something similar before which was
> > caused by a problem with the UNMDACX12 signal, but in this
> > case that's not the problem as changing the relevant chips
> > (7404 at H10 and LS191 at C9) doesn't fix the fault.
> > >
> > > This is an early Rev 2 board.
> > >
> > > Could of course be the AD561 DAC, or the TL081 or
> > TL082 in the X axis output circuit, but is there anything
> > else that I've missed before I go swapping out multiple
> > chips? I can't unfortunately see any faults when I 'scope
> > out the signals.
> > >
> > >
> > > Thanks,
> > > Phil
> > >

---------------------------------------------------------------------------
** Unsubscribe, subscribe, or view the archives at http://www.vectorlist.org
** Please direct other questions, comments, or problems to chris@westnet.com
Received on Thu Mar 11 17:49:28 2010