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Currently stumped on this Burger Time I'm working on. Graphics are as-seen in the pics. Did some reading on the forums but nothing specific to what I'm seeing. The only thing I read was from a post mentioning grounding the outputs of the LS194s after the graphics ROMs. Doing that doesn't move...

Currently fighting through this graphics issue, after finally repairing a RAM error. As seen in the picture, the images are all there, but there are randomly spaced gaps in between the horizontal lines of the graphics. Also, there doesn't appear to be the scrolling message on the bottom of the...

So here's an issue I'm having with a Tempest boardset. As you can see in the pictures, the alpha numerics is being generated properly, but not the graphics. There is also a positioning error, as when it displays the high score table, the scores are stacked on top of each other. I've used the...

Currently stumped on this sprite issue on a DK Jr. board I'm working on. As you can see in the picture, there are equal gaps of missing sprite data. However, the data is there in between the gaps. All tile data is fine, displayed properly, so it's definitely somewhere in the the sprite logic...

Hey all, Working through a Space Duel that was hit by overvoltage, as 15 ICs later the board passes Ram and Rom tests, but is still watchdogging. Grounding WDDIS doesn't help. Looking to see if there is Signature Analysis out there for the Vector State machine area of the hardware, as it appears...

Been digging around looking for an idea of where to look (on the PCB) for the issue I'm having with a Frogger PCB. Pretty basic issue here - when moving the player front to back, the correct sprite is drawn on the screen, but when moving the player left to right, the sprite for the truck is...

Hey all, Going through a batch of G07's and ran into this one which has me a bit stumped. As seen in the pic, towards the top of the screen, the image is not linear, but bowed. It would appear that the problem lies somewhere in the horizontal circuit. What has been done to this chassis: New...

I'm trying to work out a deal with a fellow KLOV'r on a flawless Peter Pack Rat control panel that I've had for probably over 25 years.. It is missing one of the orange buttons, but otherwise complete. There are no cracks on the control panel bend and the colors are nice and bright. The problem...

Hey all, Have an issue with my Quantum. Image has been like this since I bought it, and finally getting around to messing with it. Hard to tell from the picture kinda, but the image fills the screen top to bottom on the right side, but on the left side the image is too short. This makes the...

Recently I went through about 20 or so Centipede boards. Below are the unique issues/repairs. The majority of the board failures were related to video RAM failure, and those repairs are omitted as self-test usually indicates the bad IC. Board #1 – Background is solid yellow. 2 outputs from...

Working through a batch of 9 Millipede PCBs the past few weeks. 6 were repaired by replacing the RAMs that the self test indicated. Below are the 3 repairs that weren't RAM related. Board #1: Incorrect text characters on the screen. Scoping the graphics ROMs, pin 4(A4) of both ROMs is...

Working on some Asteroids boards, and I'm out of 2516's, so I'd like to mod a board to accept one 2764 ROM. Mark's site is down and searches haven't turned up anything so I tried to do it myself, and it's semi-working. So I removed the three existing ROMs, then plugged a 28 pin socket onto a...

Working through a batch of Asteroids/Asteroids DeLuxe PCBs right now: Asteroids PCB#1: PCB is watchdogging. Lifting pin 1 of L6 and game plays blind, so problem is in Vector State Machine circuitry. Hooking a scope to the X/Y outputs of the PCB I can see some of crosshatch test screen flashing...

Bosconian PCB #1- Does the boot up "spin cycle", displays "RAM OK" for a split second, then displays random garbage on the screen. Stays frozen on this screen. Solution - LS367 @1F was at fault. Responsible for data transmission to the video PCB. This 367 along with the other 367s allows the 3...

Hi all, I have a k4600 that was working fine, then all of a sudden the picture was shrunken both horizontally and vertically and edges of that image are all curly looking, and the washed out image that can be seen is white. Fly back makes a tick sound every so often. B+ at the blue wire on the...

Working on a Zoo Keeper currently that comes up with a blank screen and all 6 diagnostic LEDs lit. The CPU address bus lines are all inactive. E and P clocks are present at the CPU. Reset at the CPU is high. Pulling this line low momentarily does not help. What has been done so far: Swapped the...

Of all of my games in the collection, this one gave me by far the most headaches. Here's the summary: Game came out of storage, where it had sat for around 10 years. Recapped the monitor, and changed out the RAMs from 4116's to a new set of 4164s from Bob Roberts. Game played but would randomly...

Warp Warp ROM 8 error still. What am I missing here?? Been messing with this PCB for too long now and I am completely out of options. Maybe someone here might have some advice. Here is the summary: Received game, game played fine for a few hours. Turned it on the next day and it showed ROM 8...

If someone could point me to a reference as to which TV picture tubes can be used as replacements for Electrohome/Wells Gardner/etc.. that would be great, as I've seen this topic discussed before. But anyway, I stopped by the Goodwill today and picked up two older 19 inch TVs in brown cases for...

Have a Warp Warp machine that I got recently. When plugged in, it rebooted over and over. Swapped out all of the 2114's and it came up fine for a few hours. Then when it was powered on later, it shows a RAM OK , ROM 8 error. I pulled all of the ROMs and verified them on my EPROM programmer...