Re: Space Duel Blahs

Mehrtens John-LJM071 wrote:
>
> Hallo!
>
> I have a couple of small issues with my Space Duel -- it's a near-mint game,
> but I'm afraid some of the electronics are seeing the wrath of time.
>
> There are two problems which keep me from doing much with the game (pardon
> me if these have previously been answered; I'm new to this list):
>
> First, every once in a while the unit will show a dot on the center of the
> screen along with the rest of the XY chars. Could this be 'lytics that are
> drying up? Driver circuitry? Any suggestions?

this is normal. There is aways a faint dot in the center. If it is brighter than
normal then you may want to try adjusting it out a bit with the screen brightness
control on the HV unit.
   I don't believe that dried out caps could really cause this, as far as them
adding ripple at least. Usually getting the best picture is an art of messing with
the drive controls and the brightness.

>
> Second, audio is disappearing (Just certain effects - like ship explosions -
> but not the whole shebang). This, I believe, is bitrot... My EPROM
> programmer handles 2716+, not 2708's (no write voltage for them) or I'd
> compare/reprogram them with ROM images I have. Is this a fairly accurate
> assumption?

Space Duel is all 2716's and 2732's I believe. I doubt it would be bitrot or you
would have an error in your self test screen telling you that you have a bad ROM.
I would suggest cleaning your volume potentiometer, or maybe reseating the POKEY
chips (2 big 40 pin IC's right next to each other). Also, check your voltages (+15V and
-15V spcifically) as they power the Op-Amps for the sound circuitry. Make sure you don't
have any burned pins on the big edge connector on the game PCB as well, if it has been
running for a long while, then you will want to stop any heat damage as soon as possible
on your edge connector as they get more difficult to repair the farther along the damage
gets.
  This is all sort of a mish-mosh of general suggestions that should help you along
initially. Good Luck!
 jess
>
> Any help would be greatly appreciated.
>
> John
Received on Mon Oct 18 11:51:39 1999