Williams Joust Playing Blind

72gto

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As mentioned in a previous thread (same machine, different issue) we have added a 1982 Williams Joust Machine. We dragged it home two days ago and after a lot of trial and error it is now beginning to show signs of life.

Now when powered on the segmented LED shows "0" with no error codes as shown in Pic 1. There are two of three led's solid on another board as depicted in Pic 2. The middle Led (#2 is off if that is significant). I think all that behavior is normal, but I could be wrong.

The game will coin up but has no display, not even the characters in Pic 3. The monitor is a WG 19vjtp22 model. I think its playing blind (as opposed to attract mode) but the noises and sounds on this game are very random.

So the game will play when coined up but absolutely no display even from its first boot. But here is the particularly odd thing: once started, if I hit the hard reset button on the upper left corner of the board (straight up the board above the bank of batteries), it will display some characters on the monitor as depicted in Pic 3. The characters will stay on for about a minute and then the monitor will go completely blank again and the behavior cycles over again.

Any suggestions where to go next? I surmise that this is not a monitor problem, but am I right about that?

Also, I'm aware that there's a diagnostic function. I cant see a readable test screen or counter when using the the test buttons but can get it to display with what I thinks is a garbled rug pattern underneath as shown in Pic 4. That will stay for as long as I will allow it (I let it go for about 10 minutes one time) but that pattern will go out if I coin the game and the cycle will start over.

I hope to hear some ideas and as always appreciate the help and insight.
 

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I would start by testing the output of the power supply with my handy dandy multimeter and see if it is outputting the correct voltages for the game board to run correctly. wether or not it is outputting the correct voltages, it probably needs to be rebuilt anyway so good luck with that.

monitor chassis probably needs to be rebuilt too. I would rebuild it if it were mine and test it with a known working game to see the beautiful colors and then you know it's good to go

these days, any new to me game "find", probably needs the power supply and monitor chassis rebuilt for long life. pretty amazing how much people want for these games that need all this work done to them. big job ahead of you and learning curve as well.
good luck and hope you are successful

how much did you pay for all this soon to be had learning experience ?
 
I'm in for $200 and about 2 hours so far. It had only garbled video when I first saw it and no signs of life as to the game itself but at the time the power supply was only generating 3.5 v. to the board. Put a switching power supply in it just to see what I had and appear to have the game operating but negative on the display as noted above.
 
depending on the monitor. Look for Horizontal hold or horizontal frequency and give that pot a turn.

Also, almost looks like a CGA signal on a EGA monitor. Can you post pics of your monitor?
 
Gamefixer -- your suggestion on the monitor signal has me perplexed but is very much appreciated. (However, in general it takes little to perplex me and certainly takes even less as I try to absorb vast amounts of information here). I'm unsure of what monitor shots you wanted but will assume that you were identifying the chassis for the rastor and signal. (I'll take pictures all day if it helps find a cure -- the monitor chassis ID is WG 19vjtp22). FWIW -- I don't know all the history of the machine but I was lead to believe that if it did not have this monitor originally that it at least that it had employed this monitor during a time when it was playable before long term storage. Still doesn't mean that its hooked up correctly, etc., but logically it would seem to me that it's unlikely that the signal is incompatible with a new and different monitor. That said, I don't really know the implications of poor B+ voltage etc. and what that might look like, but I'm 100% with you on the hz hold, etc.

I'm really thinking this is a power problem. Anyone please tell me if you disagree, because I can at least get the garbled Joust screen EVERY TIME I hit reset. That tells me that something is generating a signal for at least a minute. However, that said, when I test at the board I'm getting 5.0 v. at the +5 connection and the internal segmented display is always showing the "0" for the segmented display indicating the logic is working. But I also have -5 and 12v coming into the PCB itself. The 12 v is off at about 11.6 v. (I purchased the arcadeshop.com Williams switching power supply kit and will know soon enough). (FWIW. It did have an extra D8784 power board that came in the sale. That indicates to me that someone was noodling around with the idea of a power issue. Either they misdiagnosed with the same troubleshooting I'm doing or didn't get around to it).
Also, before the discussion may digress to linear v. SPS, I'll defend myself -- I wanted to be able to adjust the voltage and saw that I'd have to rebuild and modify the D8784 board to add the pot. I know that add looks simple but I don't want to have a dozen separate projects before I even have a picture or confirm the game is playable and can always use the SPS on something else.

In conclusion, I'm barely up to the level of generally understanding JAMMA boards and how the electronics are working. To my untrained eye this this thing is exponentially more complicated. However, the behavior at resetting and the different +5 and +12 voltage supply at the logic board is really throwing me. I have no idea where those voltages are going on the board. Is it possible that the logic on this board powered by +12 and not +5? Anyone have any insight?

Lon -- I need you buddy!
 

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the monitor you have there is a Wells K4600. The part number you quoted is the tube which can be used on a lot of different monitors.

Anywho....

You dont have a power problem there. You either have an output issue from the board or the horizontal frequency/hold is off on that monitor.

On the k4600 there are two places that you can adjust the horizontal control. First one is a well marked pot on the X/Y control board. See pic attached.

The second is the adjustable coil marked L351 in the attached pic. You are really supposed to use a plastic adjustment tool to turn this thing but if you are careful and pay attention to what you are doing you can use a small metal screw driver. There's a hole in the chassis that leads to this coil. You can run the screw driver through the hole to get to the coil. I usually turn the monitor off, place the screw driver in the hole and get it lined up with the coil adjustment screw then power the monitor back up, make my adjustments and pull the screw driver out.

This board is the one on the right hand side standing vertically off of the main chassis.

You should also be aware that those chassis are well known to have cold solder issues on both the main chassis and the two vertical expansion cards.

The k4600 is not a newb friendly monitor at all. :)
 

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Thanks again Gamefixer.

So here's a question I ask only so that I may understand better. If the problem were cold solder on the monitor chassis, why does a hard reset on the board cause it to display something while at all other times its displaying black? (It seems like the trace would cause a malfunction at all times so that nothing was ever displayed OR consistently have a garbled picture. However, I get that garbled display Joust display every time I reset for about a minute then it goes away. Also, I can get to the troubleshooting menu to get the garbled rug pattern which also displays for as long as I'll let it -- wouldn't it also display only black and not behave by coming on at a specific time and then consistently going off to black at the same specific time. Basically, I know the connection could cause a garbled trash display OR to show no display at all -- but if the signal comes from the board to one point on the monitor why some video signal consistently causing some display to come on or off by doing something at the board and what would cause it to go black after a minute?

(DUH -- my bad, good to know how I missed the model number. There was another label with a RCA tube number on it so I thought I had ruled the tube out by elimination and had a good model number).
 
Hmm.. I missed the part of it being blank than displaying a picture only after you hit the reset button. Yeah, thats an output problem from the board for sure. Something isnt starting with the rest of the board. Its after the "software" side though since the game is coming up. SYNC generation, blanking. something along those lines.

Any sort of acid damage on the board?
 
Nothing that's visible to my eye. Plus, this has the AAx3 battery holder at the bottom left of the board mounted vertically. While I don't have any experience with Williams machines, thanks to gravity, if there were corrosion it wouldn't seem like it could get to anything where its located and how its mounted.

So I'm still thinking power. However, I'm still confused where the board is to run on +5 and +12. My +5 appears good, but the +12 appears low. I guess that could be a problem but it seems strange that the game logic would run on 12 volt (if that were the case).

Anyone out there have some direction on what voltages to check where on the board?
 
I really dont think its power but maybe, just maybe....

And battery damage doesnt really care about gravity, its the out gassing from the batteries that does the damage. That gas is going to go where ever it wants too.

So do this. Reset it to get that image you started the thread with. Then see about getting the horizontal issue figured out.

one thing comes to mind. The SYNC is derived from some internal counters on the CPU board. If they are wrong/bad you could get exactly whats described here. In order to find out you will need a scope though. You could see the counters with a logic probe but you wont be able to tell if they are really working right.

And seeing that its horizontal only I really think its a monitor adjustment. I mean, it could be the output device that drives the horiz hold but its not likely.
 
Could really use any more input you experts may have.

This evening I replaced an existing ATX POS power supply with the arcade shop Williams switcher. Once I had everything hooked back up, the behaviors are the same as previously described above.

Specifically, (1) at power on the ROM and RAM boot test cycles and the display on the segmented display comes back with "0" like normal; (2) it will coin up and play (but with nothing at all on the display); (3) if I press reset, the monitor WILL display a garbled "Joust" text image (as shown in far right pic) for about 30 seconds and then go black; and (4) -- this one is new -- I monkeyed around with the diagnostic menu buttons (I can't actually see any text through the dx menu selections") and got the images displayed below. It will do the same in each colors separately or together in a test pattern of some nature. Obviously there's at least adjustment if not a more serious problem with the monitor.

The monitor is the WG k4600. If anyone recognizes the condition that would cause the monitor to display looking as it does please tell me what to adjust. I figure at this point I'll start with the monitor display in the test menu and work backwards. The display is not rolling in any manner although it looks that way in the photos. The screen is perfectly constant as you see it in all three photos.

I'm still hard pressed to understand why I have game play with no picture at all but can get the monitor to display some poor images simply by resetting. Clearly there is a monitor display adjustment needed -- but I don't see how that keeps the game from displaying SOMETHING during play, even if nothing more than a garbled image.

I'm ready to follow any new direction and did deeper.


(A note FWIW -- the +5 voltage at the switcher is spot on at 5.10 at the board, but the -5 voltage is -4.8. The problem is there's only the one adjustment. Does anyone know how to get the -5 v. up without increasing +5 so that it may risk cook something. Is this problem common? I've not had it on my other machines)
 

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negative 5 being a bit low isnt the issue here.

Something new is going on there. Your first post it looks like the horizontal frequency is off. The first two pictures in your last post, those dont look right at all.

Did you try adjusting that pot I pointed out that needs the screw driver?

As far as not having a signal upon cold boot, thats a board problem. Depending on your soldering skills you could go at the board but you should do it with a logic probe or a scope beforehand.

If you are not comfortable with the above mentioned PCB work there are several people in this forum that can work on those boards. Including myself.
 
virtually every 4600 that's in circulation that's never been worked on will roughly have the same exact problem, and it's in the cards. the unfortunate part about 4600s is that taking them apart is akin to working on a car, and you also have to deal with the width coil too -- which I've found best is to just cut the wires off it, do whatever work you need to do, and then solder them back on. the solder to the header pins the cards plug into will most often be cracked. some monitors will still work fine like this, others will exhibit all kinds of issues.

adjusting L351 is a task alone, if this is out of adjustment you will get what appears to be double images like you're experiencing. probably the most appropriate way to go about fixing it is to replace all the caps, which, once again, is a huge ordeal not because it's hard, but because there's so many parts. there's a 3rd board that plugs into the chassis on the heatsink wall as well.

you will probably need help. your game board works fine.

EDIT: -5 is an unregulated voltage. it will never be exactly -5.00, same with +12, that will actually probably be closer to 13.5V. neither voltage matters that much, they have a wider operational tolerance than +5 to begin with.
 
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Mecha, you've helped me out of jam on two occasions so far and have not steered me wrong. I don't think Gamefixer above would disagree with where you're landing -- but I don't think he had entirely eliminated the board. If the consensus is that I have a monitor problem, I believe that's good news since the game is more scarce than the availability of monitors.

But please help me understand this aspect of it: if the board set is regarded as fine and the problem is entirely isolated to the monitor, why do images come on and off by resetting the game or by going into test mode? I'm just asking because there's obviously something I'm not getting between A and B that would allow the behavior to be effected by doing something at the board but still be entirely isolated to the monitor, I don't understand what that would be. Logically, if I used a test pattern generator and had signal and image at the monitor, wouldn't that show a problem on the board? (I don't have a TPG in the toolbox, but should I do anything like that before addressing the monitor or is it that obvious that the monitor is the culprit?)

Given all that, I'm roughly between Cincinnati, Columbus and Indianapolis. I'm reading between the lines that this monitor is above my pay grade -- believe me, you don't need to tell me twice. Is there anyone within a 100 mile + or - who I can bring the WGK4600 to for repairs? If I had to mail it for repair would I just mail the chassis to someone or the whole CRT and chassis. Rather than repairing, should I just replace it with something else? If so, what would be in the wheelhouse of a noob for this monitor project and any suggestions for a source?

I apologize that this thread is going every which way with what appears to be literally every aspect of troubleshooting and repair. Someday it will be solved and Lon can park it in the appropriate spot in the Joust Repair Log.
 
Based on your last group of pictures I think you have 2 problems.

1) The monitor issues need to be address, specifically adjusting L351. Its really easy and can be done with a small flat head screw driver so long as you are careful. I think that would get the picture to where its a correct image. You may still need to change caps and repair cold solder but thats for later.

2) you have some sort of board issue based on the no output upon cold boot. That could be a lot of things, its not as simple as some one telling you to replace an IC on the board.

FWIW, I can work on the 4600 and the game boards (as can many others) if you decide to ship for repair.

Know this though, taking apart the k4600 is the harder part of fixing it. If you can in fact remove the deflection board and flyback from the frame you've done the hard part. Following a cap map is easy compared to dealing with taking that monitor apart. If you were to ship you would not need to ship the CRT, just the boards.
 
Ive seen something similar to boards with alkaline (battery) damage.

I think it may be a cable or header pin. Or. Cap on the board.... Its stuck on a rug pattern... But coin up resets it? Thats a new one for me.

I know the 4600 may have an issue... But that rug pattern looks like it should.

I have a 4600 in my pacman.... I get vertical collapse... Bang the side... Back up and running... Cold solder somewhere.... I'd fix it but I have yet to see a width coil or flyback popup for sale recently.

I wonder of that coin switch has a capacitor on it
.. And its triggering something on the board with a little boost.... That I've seen.
 
LovelyCoCoNuts -- I may not have been clear before. Its not displaying anything at coin up. It's playing blind and at that point there's no image. However, using the reset button on the video/ram board will cause the monitor to go back through self test and briefly display the Joust Logo before the screen goes blank after about 30 seconds. It notably does not do this at start up. You can repeat the process and force that image over and over and you can also force a display through the test/menu buttons at the coin door but constantly no display at all during game play.

Gamefixer, in case its relevant when you took note of the difference between the first and second screen shots, I'll fill in some blanks.

After my first post, I did adjust horizontal hold and size. The result was to stabilize the image so that it wasn't rolling and favorably aided the curl at the side edge. After you suggested it I did very modestly adjust (like 1/16 of a turn in either direction) the L351 as you advised. I most likely did not adjust it far enough to do anything but I got spooked I might make it worse with the little image I had. I should have asked this before, but in lay terms what does the L351 adjust exactly, what do you expect it to do as its adjusted one way or the other and how do you know when you've gone too far? Is it as obvious in its effect on the image as say purity or horizontal hold would be to know you're messing it up or is it something that can really screw things up like B+?

I have other cabs here but no Williams. So I can't really swap the boards into another machine. I've swapped the boards between the JAMMA machines before to troubleshoot problems at the suggestion of others. It would seems like I could do that with the monitor itself -- but so far no one has suggested that and the prospect of damaging a second monitor in the process seems very real. Without stating the question very artfully, that's what I was getting at with using a Test Pattern Generator simply to see if I could isolate and troubleshoot the monitor problem separately from the board.

Having read a million threads at this point and dozens of Youtube videos, I think I can muster the confidence to discharge the anode and remove the monitor without killing myself. Evidently dangerous if not discharged correctly -- but unless I'm mistaken not overly complicated. Taking off the board from the chassis doesn't seem to be too involved either and I did reseat the one with the display signal wires. While I'm tempted to try to recap it myself as you implied for the learning experience, I know myself well enough to realize I'd be beating myself up if went through all that work and delay and still didn't fix the problem (or worse yet, caused a new one mostly because I'm not using the right tests/procedures, etc. on the right problems). Best to leave it to the experts and remain a humble apprentice trying to learn from the mistakes of others, not teach them.

I see there's several moving parts with this machine that may make its repair multiple pronged. I'd be interested in having you take a look if your free and if it won't cause me to spend my retirement savings on a $200 machine. I'll send you a PM if that's okay.

Really appreciate the feedback, insight and suggestions.
 
Gamefixer, in case its relevant when you took note of the difference between the first and second screen shots, I'll fill in some blanks.

After my first post, I did adjust horizontal hold and size. The result was to stabilize the image so that it wasn't rolling and favorably aided the curl at the side edge. After you suggested it I did very modestly adjust (like 1/16 of a turn in either direction) the L351 as you advised. I most likely did not adjust it far enough to do anything but I got spooked I might make it worse with the little image I had. I should have asked this before, but in lay terms what does the L351 adjust exactly, what do you expect it to do as its adjusted one way or the other and how do you know when you've gone too far? Is it as obvious in its effect on the image as say purity or horizontal hold would be to know you're messing it up or is it something that can really screw things up like B+?

Basically, adjusting L351 adjusts the "over all" position of the horizontal hold. The pot facing outward on the same board "fine tunes" the horizontal hold. You may effect the b+ but it would be minor.

You know when you've hit the right spot when the image on the screen is normal or at least is legible but may have a slight curl, which you can adjust out with the other pot.
 
So taking the advice by Gamefixer and Mecha, I've adjusted the L351. I thought it might be useful to describe the response.

The image you see in the pictures above is exactly what I see. Because the photo represents a still image, I can imagine someone would think they are seeing the same artifact being imaged over and over across the screen (like when horizontal or vertical hold is way out of fact). But its really not acting that way, meaning the image is not rolling in any way and is stable. As I adjust the L351 the image THEN starts moving and rolling and becomes unstable.

Does that change the analysis at all? For sure, L351 isn't fixing the image.
 
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