Check the z-circuit on the game board. I had a Battlezone that would
produce a complete image on the screen, and then the bottom portion
would fade out. Hooked up to a scope I would get a perfect, full
picture.
tm
MKDUD@aol.com wrote:
> Hello,
>
> I have a Battlezone AVG board that boots up fine and passes
> self-test. After replacing several dacs, the board was working fine.
> Now, the right half of the screen is missing, and I know the problem
> is not monitor related. The rscreen was fine, and the right side just
> started gradually fading out, and now just the left side is there.
> (these pics are big):
>
> http://members.aol.com/mkdud/BZ/bzhalf.jpg
>
> I just noticed that another working BZ AVG board that I have has
> a 1N270 diode that goes from where the X Center pot would be (kathode)
> to ground (anode). Does anybody know what this diode does? The board
> that only shows half of a screen does not have the 1N270, and it looks
> like it never did. When were these added, and what for?
>
> http://members.aol.com/mkdud/BZ/xctr1n270.jpg
>
> Also, why do some boards have mylar caps attatched to pins 1 and
> 2 of the TL082s?
>
> Please help if you can,
> Thank You,
> Michael Kelley
---------------------------------------------------------------------------
** 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 vectorlist-owner@synthcom.com.
Received on Mon Feb 24 06:29:04 2003
This archive was generated by hypermail 2.1.8 : Fri Aug 01 2003 - 00:34:21 EDT
