K7000 horizontal lines in picture

Depends on the lines. Could be brightness, interference, etc.

But you probably need to adjust the 50/60-Hz pot...
 
Where is that? I'm really starting from scratch here. Just got the monitor repaired and I'm still tweaking it. Lines are only visabe in dark areas. Thanks.
 
So, not all on one side of the pic? I think you need to post a pic of the issue so I can be more specific on what to do...
 
id have to see a pic..

if the monitor is mounted horizontally, and you have vertical jailbars mostly on the left side of the screen
(or if its mounted vertically and you have horizontal lines on the top half)
, replace c56 or 57 (cant remember which) and recheck. Ideally youll want to replace all the caps if thats the issue.


if the monitor is mounted horizontally, and you have horizontal lines at a slight angle, like this: (keep in mind this monitors mounted vertically)
200px-Colguide_2_raster_lines.jpg


then those are raster lines. back off the coarse brightness on the flyback untill they go away then readjust everything else to bring back the screen intensity.
 
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Old thread, still helpful. That was exactly my issue. Backed off the screen adjustment on the flyback and upped the brightness on the board and tweaked the contrast. Picture looks fantastic.
 
Hey everyone,

Old thread but hoping for some help. Tried the tips and my screen went from the first picture to the second picture. It doesn't get any RGB signal.

Have tried continuity testing from the PCB board and also reset the neckboard pins.

Tested the PCB with this monitor in a different cabinet and JAMMA harness and it worked. Now that the monitor and PCB has been moved to another cabinet with a new universal JAMMA harness, not seeming to get any RGB.

Any ideas?
 

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Can you turn that down where the screen goes black, or is that a fault (that it always looks like that)?

Another thing you can try to narrow it down just so we understand what's going on is, just unplug the game pcb for now and turn it on, see if you get the same thing. Just trying to make sure it's a monitor issue, the way I'm understanding it is you get no video, and the screen is always white like that and won't turn down to black.
 
I can turn it down and it goes black. It's getting power, no picture.

Unplugged the PCB and it was the same.

Did a continuity test from the actual edge of the PCB through to the end of the RGB cables on the harness and it was a working circuit, so it seems the PCB is sending and RGB signal.

I wonder if something was jarred in the transferring between cabinets?
 
It just looks to me like the pcb isn't booting, can you hear it playing? The way the monitors work usually you would lose 1 color, not all video. You have a screen voltage a high voltage and a heater voltage, all those are working, then you have a voltage on the transistors that makes the image appear, it may run through a processor chip or something but all of that is really rare and wouldn't really happen while moving it.

There's a small chance the neckboard came unplugged from the main board somehow, depending on what chassis model that is, but the simplest answer is the board itself just isn't booting up, which game is it and can you hear it playing?
 
It's an NBA Jam board. Can't hear any sound because it turns on in attract mode and the settings are silent unless you go into the test menu and turn on attract mode sound. The red LED does light up when it's turned on. The neckboard is plugged in, have removed it to check it and reset it in case that was the problem.

When I adjust the individual colour drives and cutoffs, you can see more/less red/green/blue, so that seems to be working.

Is it possible that using a 'Universal JAMMA harness' where all of the grounds (including video) are going through the top two pins on both sides instead of also in pins 14 and 28 as it was originally intended?

Also, a complete rookie move, but also noticed that when hooking up the PCB to the black box power supply, forgot to wire the FG to the ground post on the transformer power pack. Maybe this was not good for the PCB and has caused this issue?
 
That field ground doesn't matter in this instance for now.... when NBA Jam first comes on, regardless of whether the attract sound is on it makes a loud "BONG" noise, so you should hear that.... although to complicate things, that would only really mean that your sound board has a problem which as i'm sure you've noticed on NBA Jam is a separate board. Also when you go into test, if the attract sound is silent, you still hear noises on the screen as you move from option to option. If you coin up the game with attract mode sound turned off, you also hear a noise when the credit is added....

So all that to say, I don't think your board is booting up, and your monitor is likely not the issue.

All the red led on the PCB means is that some power is getting onto the pcb, it doesn't mean the game is actually running and putting out video. Next step would be to get a multimeter and see if you have 5 volts on the main pcb, if it's 3 volts for instance it would still light up the LED but the board wouldn't boot or generate any video.
 
Awesome, thanks very much for the wisdom. Will try it tonight to see if it's getting 5V and report back the findings.

Still can't figure out, though how it worked in a different cabinet and not this one, although it is possible that something went between then and now. It has to stop working sometime if it isn't going to work.

Also, accidentally knocked the Y1 crystal off the sound board the other night, will re-solder it back on.
 
The power to the board runs through a few pins at the end of the jamma connector, if any of those don't make good contact or have corrosion or any kind of resistance it can lower the power that makes it through, if you get down below 4.5 or so the board may not do anything. I know you said it's a new universal harness but if the wires are thinner for instance, they won't allow as much amperage through and would lower the voltage too.

When you check the power too, you need to check it on the board, not on the power supply. If it's much lower on the board than at the power supply, you've got resistance somewhere or the wires are too thin.

NBA Jam is well known as being a power hungry board, it takes a lot of juice.

If you knocked the crystal off the sound board of course it's definitely not working so who knows what's going on.
 
The power to the board runs through a few pins at the end of the jamma connector, if any of those don't make good contact or have corrosion or any kind of resistance it can lower the power that makes it through, if you get down below 4.5 or so the board may not do anything. I know you said it's a new universal harness but if the wires are thinner for instance, they won't allow as much amperage through and would lower the voltage too.

When you check the power too, you need to check it on the board, not on the power supply. If it's much lower on the board than at the power supply, you've got resistance somewhere or the wires are too thin.

NBA Jam is well known as being a power hungry board, it takes a lot of juice.

If you knocked the crystal off the sound board of course it's definitely not working so who knows what's going on.

if you have a junk Chinese JAMMA harness, beyond that no. I run the Jam TE at my work at 5.05V; it's never given me grief.

MK1 was the only T-unit game that was stupid about power; ironically you have to run it at 4.90V at the chips. too high and it'll consistently reset at Goro.
 
You were right. It was the voltage to the PCB. Cranked it up, heard the BONG and now we are playing. Thanks for the great advice.

Any tips for how to solder the Y1 3.58 MHz crystal back to the sound board? Finding it really difficult.
 
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You were right. It was the voltage to the PCB. Cranked it up, heard the BONG and now we are playing. Thanks for the great advice.

Any tips for how to solder the Y1 3.58 MHz crystal back to the sound board? Finding it really difficult.

just get a new one.

https://www.mouser.com/ProductDetail/815-AB-3.579545-B2

funny Williams stuck with the same crystal type as their old games. LOL I never looked into it on ADPCM sound boards before.
 
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