JAMMArcade.net – Page 12

Desert Breakers repair log

Dec 302019

Bought a cheap Desert Breaker for my collection which the seller declared as having no sound.

This game is running on system18 hardware. Since the sound was totally missing I first tested the z80 which was good and then I desoldered the SRAM which was

a Toshiba @IC79 , normally very unreliable in comparison to other makers and infact it was faulty.

It fixed the sound but playing I noticed that some sprites had missing lines

This problem could be either the custom chip 315-5361 ( sprite generator ) or the srams connected to it ( IC21 and 22)

Since all the address line were good, I proceeded to desolder and test the srams which were infact bad bad.

Game was fixed totally

Asterix repair log #2

PCB Repair Logs Comments Off

Dec 202019

A fresh box of broken boards from Muddymusic arrived recently and Asterix was the first one I pulled out.
Here is the picture I was sent of what it does on boot up

That’s reporting a couple of bad RAM chips but when I did the visual inspection I saw what looks to me like some reflow work has been done in the past and been done badly too. Excess solder and a couple of lifted traces. There were also some bent pins.

I straightened out the best I could and patch a couple of traces too.
The game now passes it POST but I get this in game

At first glance this looks OK and I initially missed it until I ran the MASKROM check from the test menu and it reported a failure at 7K (no picture of this, sorry). If you look at the “ASTERIX” logo there are a few issues around the outline with blue parts.
Going back over those customs and checking all the pins individually I found one pin that needed reflowing. Doing this fixed all the issues.

BINman update

General Comments Off

Nov 082019

Updated BINman to support IPS patching (v4.6.0).
Recently needed to patch a file so though i best add it. Its not thoroughly tested but im sure bugs will be discovered in time and i will fix it.

Ninja Spirit repair log

Repair Logs Comments Off

Oct 262019

I have a ninja spirit on my collection since more than 10 years. I play it regularly but the other day it once powered up the foreground layer had some vertical black bars crossing the screen for the complete height on the right side.

After a while also the left part started to blick glitching ( cannot be seen on the screenshot below unfortunately)

The board is an irem M72 and the background and foreground layers are handled on the bottom board. The circuit for both playfields is completely the same.

Schematics are available for Rtype which is the same hardware minus the C board.

I checked immediately the circuit which draws the foreground and decided to check a couple of TTL

With some luck I immediately found one 74ls283@10A (IC 78) which was glitching badly the left part of the screen when testing with the probe on pin 10.

74LS86@7B ( IC50)was also glitching the screen when testing with the probe on pin 6