Sign in with
Sign up | Sign in
Your question

Tech help: Galaga PCB - enemy not registering a hit in sco..

Tags:
  • Video Games
Last response: in Video Games
Share
Anonymous
June 12, 2005 4:14:13 AM

Archived from groups: rec.games.video.arcade.collecting (More info?)

Hopefully someone has seen this before and can help. I recently purchased a
Bally/Midway 2 board Galaga set from the newsgroup.

Unfortunately it was not packed to the best standards (it arrived against
the bottom of the box in the corner with only crumped newspaper filling the
rest of the box :(  ) The box had some smushing but nothing terrible. I
couldn't see any physical damage to the board other than a couple of the
board spacer plastic pieces were broken and I replaced them.

Anyway, in demo mode the following happens: When the scoring page appears,
and the first set of ships (on the right side) dive down, the player
(computer) fires at it, but the first bullet goes *through* the enemy and it
doesn't respond like it was hit. Then the next bullet turns the enemy a
darker blue and then it procedes to go through the player ship and off the
bottom of the screen.

When I loaded the game up in mame it showed that it was hit twice and turned
to 1600 points showing on the second hit--on all the various versions of
Galaga. What could be wrong? A bad eprom? Bad ram? Something else?

Oh yeah, one other thing... while sitting in demo mode once (while I was out
of the room) it suddenly got stuck and showed "Credits FF" and kept
replaying a sound, and I had to hit the reset button the board.

Thanks in advance! Please post any solutions to the group.

More about : tech galaga pcb enemy registering hit sco

Anonymous
June 12, 2005 7:37:03 AM

Archived from groups: rec.games.video.arcade.collecting (More info?)

On Sun, 12 Jun 2005 00:14:13 -0500, "BF" <BFfargo@yahoo.com> wrote:

>When I loaded the game up in mame it showed that it was hit twice and turned
>to 1600 points showing on the second hit--on all the various versions of
>Galaga. What could be wrong? A bad eprom? Bad ram? Something else?

This just sounds like a fast shoot chip is installed. It does mess up
the attract screen. How's it play otherwise?

Best,

- Mike -
Anonymous
June 12, 2005 12:19:09 PM

Archived from groups: rec.games.video.arcade.collecting (More info?)

Clean the socketed chips (and thier sockets), especially the customs
which are almost always black with oxidation. The best way I've found
to do this is to use a Dremel with the little wire wheel. Very gentile
on the chip pins and cleans 'em up fast. Before reinserting the ic into
the socket, hit the socket with some good contact cleaner/preserver
(Caig Pro Gold or something similar) and reseat a few times to scrub
the contact points a bit.
I'll even coat the non socketed portion of the pins with some Caig to
prevent future oxidation....or at least slow it down.

Galaga pcb's do strange things when they're due for some attention.
Anonymous
June 12, 2005 11:39:33 PM

Archived from groups: rec.games.video.arcade.collecting (More info?)

Hey Mike.

Thanks... You're right! I added the cheat and got the same effect in mame.
Everything else seemed to play fine.

I assume I just need to burn 3600e.bin from the rom archive to replace the
3J chip on the Midway board to fix this, right?


Regarding the other issue.. random reboots. It's only happened twice, both
times after a cold boot just after the 1st complete run of the attract mode.
First time it froze after rebooting, the next time it said Ram 4L I think.
But I was able to play for 20 some levels and no strangeness after that.

I tested voltage was 5.20 at the switch mode power supply, but 5.06 at both
leads of the capacitor next to the power plug on the PCB. (I havn't tested
individual chip voltages yet, but presume around 5.06 once it's on the
board.

Whats the maximum "safe" 5 volt and 12 volt lines I should be running into
the board? My 12 v is actually kinda high.. around 14 volts.. is that safe
or too high? That only goes to the audio amp, correct?

Thanks in advance!

"Mike Haaland" <mhaaland@mikesarcade.com> wrote in message
news:uf0oa15r42mu7qgt580q33no93pv363bp8@4ax.com...
> On Sun, 12 Jun 2005 00:14:13 -0500, "BF" <BFfargo@yahoo.com> wrote:
>
>>When I loaded the game up in mame it showed that it was hit twice and
>>turned
>>to 1600 points showing on the second hit--on all the various versions of
>>Galaga. What could be wrong? A bad eprom? Bad ram? Something else?
>
> This just sounds like a fast shoot chip is installed. It does mess up
> the attract screen. How's it play otherwise?
>
> Best,
>
> - Mike -
Anonymous
June 13, 2005 3:30:57 PM

Archived from groups: rec.games.video.arcade.collecting (More info?)

On Sun, 12 Jun 2005 19:39:33 -0500, "BF" <BFfargo@yahoo.com> wrote:

>Hey Mike.
>
>Thanks... You're right! I added the cheat and got the same effect in mame.
>Everything else seemed to play fine.
>
>I assume I just need to burn 3600e.bin from the rom archive to replace the
>3J chip on the Midway board to fix this, right?

Right, if you want a working attract mode that does the right thing.
The other option is the Galaga Enhancement Pack. It has dip
selectable fast shoot and a correct attract mode.

>Regarding the other issue.. random reboots. It's only happened twice, both
>times after a cold boot just after the 1st complete run of the attract mode.
>First time it froze after rebooting, the next time it said Ram 4L I think.
>But I was able to play for 20 some levels and no strangeness after that.

Dirty customs, or weak sockets on them can cause this.

>I tested voltage was 5.20 at the switch mode power supply, but 5.06 at both
>leads of the capacitor next to the power plug on the PCB.

I run them here on the bench just under 5VDC. Overvoltage, like many
folks recommend, is just shortening the life of the chips, IMHO. If
you have to crank up the voltage, there is something wrong with the
board.

Best,

- Mike -
!