Tech: help with disconnected wire on a Pac Bootleg 3 board.

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

Hi all,


Hopefully someone can help me with this.
I have what appears to be a Bootleg Pac 3 bd. It has a small board (about
the size of 2 postage stamps) screwed to the upper right hand corner(not a
little black box). The small bd has 2 resistors, 2 caps, a 8 pin chip and a
pot.
There are 3 wires coming off it connecting it to the main bd,
Grn, Yel, Org

Green is attached to PCB gnd

Org is attached to main connector pin 18

I can't figure where the yellow goes, it was disconnected when it came in.
Looking at the board closely I can see a few places where it could go.

When the game came in it would lock during boot with 1, 2 or 3 characters on
the screen.

Pin 4 of IC at loc 9D has been cut out.

2 set of 2 pads between 9E & F have been jumped.

I tried to solder the yellow to the pin 4 pad at 9D and I get the same boot
problem.

I tried to disconnect the 3 wires completely but I get no video at all.

I tried to connect yellow to 5M pin 5, no boot.

If someone could tell me where the yellow wire goes...
I saw nothing obvious...


I can send pics to anyone interested in seeing them.

Thanks


Mike Singer
AVP-Ellicott City, Md

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

Mike Singer <pinbuoy@comcast.net> wrote:

That's an aftermarket speedup hack, most likely.

The chips probably a 555 timer IC, and it's used to generate interrupt to
the CPU, instead of the vsync line.

The yellow probably needs to go to 9D:11


: Green is attached to PCB gnd
: Org is attached to main connector pin 18

That's +5V

: I can't figure where the yellow goes, it was disconnected when it came in.
: Looking at the board closely I can see a few places where it could go.
:
: When the game came in it would lock during boot with 1, 2 or 3 characters on
: the screen.
:
: Pin 4 of IC at loc 9D has been cut out.

That should be a pullup for the 7474 n the hsync circuit... no reason why
that should be cut.

: 2 set of 2 pads between 9E & F have been jumped.

Probably the ghost names and difficulty jumpers

: I tried to solder the yellow to the pin 4 pad at 9D and I get the same boot
: problem.
:
: I tried to disconnect the 3 wires completely but I get no video at all.

Doesn't make sense that taking it off would kill the video, when the 3rd
wire goes nowehre, and the other 2 are just power...

--
Mark Spaeth mspaeth@mtl.mit.edu
50 Vassar St., #38.265 mspaeth@mit.edu
Cambridge, MA 02139
(617) 452-2354 http://rgvac.978.org/~mspaeth