Froztbite repair logs

[froztbite]

Hi, i'm still a humble novice in learning so I try to absorb a lot from other people repair logs. I have a background in software but not in hardware side so a lot of this is learning as I go. I however like to spread my fixes to as many place as possible so a fellow enthusiast might find a solution or idea to their own fixes. I have posted some of these for example in arcade-musem forums but not everyone occupies every forum or google search picks up on everything.

I will try to contain single fix into a single post with photos. I'm happy to discuss on the fixes but please don't expect deep knowledge on my part

[froztbite]

Game PCB: New Dynablaster - Global Quest / New Atomic Punk - Global Quest / Bomber Man World (different name for each region)

Symptom: No volume and low volume image is ok. Adjusting the volume slighly higher started to show pulsating image and when volume was high enough the image would stay fuzzy all the time.

Steps to find solution:

• Found a few other repair logs through google where all had one or multiple capacitor gone bad on this PCB. One repair log in particular had similar symptoms description and they replaced the largest one in the audio section.

• Desoldered the suspected bad capacitor and replaced with a new one.

Repair: Replaced a capacitor gone bad in sound circuit which was affecting image when volume was high enough.

Disclimer: I replaced every capacitor just in case after I verified the fix. My tester at least reported one of the smaller ones to be faulty as well, but didn't notice any difference in the game behaviour after replacing it. This is not visible in the pictures.

Normal Image


When sound was too high


Suspected culprit


Replacement done

[froztbite]

Game PCB: Sega ST-V Motherboard

Symptom: Sound was a mess which I can best describe that it had similar effect that volume would be turned all the way up and the speaker can't handle it but the same problem was with no matter what the volume was.

Steps:

• Found a repair log with similar issue description and it was resolved with replacing the TDA1386T (DAC). -> https://www.jammarcade.net/sega-st-v-bad-audio-samples/

• Used Audio Probe to check the output on the TDA1386T. The left channel output (18) was crystal clear but right channel output (21) had the same bad audio that I was hearing through the jamma connector.

• Desoldered the suspected bad chip and replaced with a new one.

Repair: Replaced a TDA1386T (DAC) partially gone bad in sound circuit which was ruining the fun.

Picture of the replacement done

[froztbite]

Game PCB: Golfing Greats

Symptom: Broken Konami 051550 custom chip was causing the game to not boot and it just reset constantly. Shipping company was not kind to my package and it had sustain a nasty bump.

Steps:

• Bought a replacement chip made by caius arcade from tindie -> https://www.tindie.com/products/caiusar ... placement/

• Removed the broken chip and replaced with the reproduction

Repair: Replaced a broken Konami 051550 custom chip with a reproduction replacement.


Bought this game in a lot of untested PCB from a fellow that had them stored away for around 20 years. Board looked to be in great shape and in the listing pictures the chip was still intact but shipping internationally has its risks.

How Golfing Greats arrived to me:


After replacing with reproduction

[froztbite]

Game PCB: Crude Buster / Two Crude

Symptom: Bought this as with graphic glitches. Most of the graphics were working fine but a few sections had some weirdness.

Steps:

• Checked the Mame rom files documentation that the top part of the board were the graphics (GFX) roms

• Started to check if the roms were fine in the GFX section

• While the rom check was giving ok, the placement it returned didn't match the board layout

• Rearranged the top 4 GFX roms since they wrere in the wrong order

Repair: The cause of the graphic glitches were the wrong order of the GFX roms.

Following pictures are so that left is how I received it and right is after I fixed it. Actually most of the game looked correct and I was only able to spot a few difference on the first level. Probably more would have been found if I played it further. Sorry if the contrast or color is a bit off, all of the images have been captured with my phone camera.

First of the board how it arrived and how I rearranged it


The title screen showing graphic corruption (which was also on the picture the seller showed)


The boss lower half would go in a weird color scheme. I was only able to capture the boot changing color


The stage clear screen beer vending machine had wrong colors