RE: Blinking/fading Asteroids ......... monitor problem

I think you're right in that the draw order (and even draw quantity) is
quite significant, whether it's caps, high voltage fluctuation or
transistors is the tricky bit!

The problem exists if the shot is fired in any direction - I just used the
up direction as an example. Since the problem exists equally in the X & Y
axis I'm tending to think it's some kind of PSU issue rather than a
deflection transisitor problem unless both pairs have failed in the same
way.

After changing deflection transistors on otherwise working boards, is any
iprovement in linearity noticed?

Bob roberts for cap and transistor kits or are there cheaper / better
sources?

Cheers,

Steve

-----Original Message-----
From: owner-vectorlist@synthcom.com
[mailto:owner-vectorlist@synthcom.com]On Behalf Of Marc Alexander
Sent: 28 March 2002 01:02
To: vectorlist@synthcom.com
Subject: Re: VECTOR: Blinking/fading Asteroids ......... monitor problem

I would have to recommend first changing all the electrolytic capacitors
on the monitor board(s), and maybe the power supply section capacitors of
the board that supplies power to it if present.

It may not be it! :) but work a try.

You can see all kinds of weird deflection shift problems with bad caps,
and it can do weird things depending on the drawing order of the vectors.
The game board may draw the shot, then immediately after draw the ship, and
if
the shot being deflected high vertically (loads up the power supply),
causing
it to drop voltage, then the ship is drawn immediately after, the ship will
be in a slightly different place.

Either that or you are firing right up the 'dividing' line between the
deflection quadrants driven by each transistor, and the deflection
transistors
have a mismatched spec, or minor leakage problem that causes them to do
weird things in their 'shared' band, when they are both supposed to be off,
or only on a little bit for minimal deflection on that axis.
Does it do it when you fire down on the same line? (just curious)

Cheers,

Marc

----- Original Message -----
From: "Steve Coule" <steve@coule.freeserve.co.uk>
To: <vectorlist@synthcom.com>
Cc: <phil@morris0.fsnet.co.uk>
Sent: Thursday, March 28, 2002 9:49 AM
Subject: RE: VECTOR: Blinking/fading Asteroids ......... monitor problem

> Phil et Al,
>
> I have exactly the same problem with my G05-801 ...
>
> Mine also has another problem and I wonder if you could check yours to see
> if it's just a single problem I'm chasing? If the ship is in the middle
of
> the screen pointing up and you fire a single shot, does the ship appear to
> recoil (move about 3/4mm) when the shot leaves the top of the screen and
> enters the bottom of the screen? Once the shot disappears the ship
returns
> to it's normal position. The same thing happens if pointing sideways and
> firing a single shot but the ship "recoils" horizontally. This is
> noticeable as a fidgeting ship during gameplay but less obviously!
>
> Again, it's not the board - tried many and they're all fine in a cocktail
> cabinet.
>
> Cheers,
>
> Steve
>
> -----Original Message-----
> From: owner-vectorlist@synthcom.com
> [mailto:owner-vectorlist@synthcom.com]On Behalf Of Phil Morris
> Sent: 27 March 2002 22:04
> To: vectorlist@synthcom.com
> Subject: VECTOR: Blinking/fading Asteroids ......... monitor problem
>
>
> Now here's something I haven't come across before and can't find any
> references to - when playing Asteroids, when there are only a few
asteroids
> left on the screen (less than maybe four, even just one) sometimes the
> brightness of a SMALL asteroid will 'blink' off for a few seconds, then
> 'blink' back on again. When I say the brightness blinks off, I mean that
> the asteroid is still visible, it's just not as bright as it was.
>
> It mostly (but not exclusively) only happens when an asteroid passes
> through the lower right quadrant of the display.
>
> It isn't noticeable when there are loads of asteroids on the screen, and
if
> one blinks/fades out then the rest are unaffected.
>
> Now this is definitely a monitor fault (I have the G05-801) as it happens
> with other Asteroids boards that I've also tried.
>
> I suspect the deflection board, maybe even one of the output transistors.
>
> I've checked Tom's excellent Black and White vector monitor FAQ but
there's
> nothing there that seems to be relevant, neither is there anything to be
> found with a general web search.
>
> Would anyone care to make any suggestions please?
>
>
> Thanks,
> Phil
>
> --------------------------------------------------------------------------
-
> ** To UNSUBSCRIBE from vectorlist, send a message with "UNSUBSCRIBE" in
the
> ** message body to vectorlist-request@synthcom.com. Please direct other
> ** questions, comments, or problems to neil@synthcom.com.
>
> --------------------------------------------------------------------------
-
> ** To UNSUBSCRIBE from vectorlist, send a message with "UNSUBSCRIBE" in
the
> ** message body to vectorlist-request@synthcom.com. Please direct other
> ** questions, comments, or problems to neil@synthcom.com.
>
>
>

---------------------------------------------------------------------------
** To UNSUBSCRIBE from vectorlist, send a message with "UNSUBSCRIBE" in the
** message body to vectorlist-request@synthcom.com. Please direct other
** questions, comments, or problems to neil@synthcom.com.

---------------------------------------------------------------------------
** To UNSUBSCRIBE from vectorlist, send a message with "UNSUBSCRIBE" in the
** message body to vectorlist-request@synthcom.com. Please direct other
** questions, comments, or problems to neil@synthcom.com.
Received on Wed Mar 27 22:55:21 2002