Battlezone monitor repair needed

"Plays Blind" could mean many things, including, ->

  • non-working X and Y out on main logic board; bad Z out etc
  • bad +/-15V opamp bias or other power issue on main board (or from ARII)
  • bad monitor chassis board
  • bad wiring from logic to chassis
  • bad transistors on monitor
  • bad high voltage board on monitor
So, just sending the "monitor chassis board" to someone might not fix the issue.

Got an oscilloscope? Test X/Y outputs first off of the main board.
 
"Plays Blind" could mean many things, including, ->

  • non-working X and Y out on main logic board; bad Z out etc
  • bad +/-15V opamp bias or other power issue on main board (or from ARII)
  • bad monitor chassis board
  • bad wiring from logic to chassis
  • bad transistors on monitor
  • bad high voltage board on monitor
So, just sending the "monitor chassis board" to someone might not fix the issue.

Got an oscilloscope? Test X/Y outputs first off of the main board.

No oscillioscope
 
(I was going to send this as a reply to your PM, but figured I'd just post it, in case it's useful to others.)

Realistically, it could be one of 3 things: Monitor chassis (and/or) monitor HV (and/or) game board. It's possible you could have more than one problem, which can make it harder to troubleshoot, but we can walk you through it.

I recommend properly rebuilding the entire monitor, as if the boards haven't been overhauled, they can have multiple issues, and you can fix one, and end up having something else blow in a few days or weeks. But if you rebuild them properly, they can be very stable and reliable monitors.

Note that it's possible it could be your game board, if there is an issue with the analog video output section, which is causing either the X or Y signal (or both) to be dead. However, this is easy to check with a DMM. Just measure the AC and DC values on the XOUT and YOUT test points on the game board. The DC should be between -1V and +1V, and the AC should be between 2 and 4 volts AC. (This is approximate, as it's going to fluctuate as the game cycles through attract mode.) If the AC is less than a volt for either X or Y, then there's a game board problem.

Note you should check all of the other game board voltages as well. This includes the +5V, +12V, -5V, and the +15V and -15V. Most of the test points are above the area where the pots are. Feel free to measure and post them here, along with the AC and DC values from the XOUT and YOUT test points.

Beyond that, I'm guessing you are likely seeing a red light on the deflection board, which is the spot killer. This LED lights when there is no deflection, which can be either due to no signal coming from the game board, or deflection board problems. So if it's lit, it doesn't tell you a lot. If it ISN'T lit however, that actually means the deflection board is mostly working, though it can have other issues.

Also, check if you are getting HV. One easy way to do this is to just hold your hand in front of the tube. You should be able to feel static electricity if there is HV. If there is no HV, that's part of your problem (though possibly not the only issue).

You should also replace Q500/501/502, and remove the R100 and R101 resistors from the deflection board, which are a common issue with these. See here for more on that issue and mod (see post #5, and the thread it links to):

https://forums.arcade-museum.com/showthread.php?t=403217

If you want to check the above and let us know, we can walk you through repairing it yourself. But if you want to just send the boards in, feel free to PM me.
 
(I was going to send this as a reply to your PM, but figured I'd just post it, in case it's useful to others.)

Realistically, it could be one of 3 things: Monitor chassis (and/or) monitor HV (and/or) game board. It's possible you could have more than one problem, which can make it harder to troubleshoot, but we can walk you through it.

I recommend properly rebuilding the entire monitor, as if the boards haven't been overhauled, they can have multiple issues, and you can fix one, and end up having something else blow in a few days or weeks. But if you rebuild them properly, they can be very stable and reliable monitors.

Note that it's possible it could be your game board, if there is an issue with the analog video output section, which is causing either the X or Y signal (or both) to be dead. However, this is easy to check with a DMM. Just measure the AC and DC values on the XOUT and YOUT test points on the game board. The DC should be between -1V and +1V, and the AC should be between 2 and 4 volts AC. (This is approximate, as it's going to fluctuate as the game cycles through attract mode.) If the AC is less than a volt for either X or Y, then there's a game board problem.

Note you should check all of the other game board voltages as well. This includes the +5V, +12V, -5V, and the +15V and -15V. Most of the test points are above the area where the pots are. Feel free to measure and post them here, along with the AC and DC values from the XOUT and YOUT test points.

Beyond that, I'm guessing you are likely seeing a red light on the deflection board, which is the spot killer. This LED lights when there is no deflection, which can be either due to no signal coming from the game board, or deflection board problems. So if it's lit, it doesn't tell you a lot. If it ISN'T lit however, that actually means the deflection board is mostly working, though it can have other issues.

Also, check if you are getting HV. One easy way to do this is to just hold your hand in front of the tube. You should be able to feel static electricity if there is HV. If there is no HV, that's part of your problem (though possibly not the only issue).

You should also replace Q500/501/502, and remove the R100 and R101 resistors from the deflection board, which are a common issue with these. See here for more on that issue and mod (see post #5, and the thread it links to):

https://forums.arcade-museum.com/showthread.php?t=403217

If you want to check the above and let us know, we can walk you through repairing it yourself. But if you want to just send the boards in, feel free to PM me.

Incredible post, thank you. I will dig in this afternoon and report back.
 
Ok, here is what I found. It has been 4 years since I opened this guy up, was like the first time all over again.

+5v LED is on
CR2 LED is on

X-out AC: 3.5 - 5
X-out DC: -0.3 to 0.3

Y-out AC: 2.4-2.8
Y-out DC: -0.3 to 1.7

game board voltages:
+5: 5.13
-5: -5.40
+12: 11.58
+15: 15.52
-15: -15.39

Auxillary board:
+22: 23.82
+5: 4.77

ARII:

10.3 UNR: 12.16
+22: 14.22
-22: 24.34
-5: -5.18
+12: 11.79
36AC: 18.31

That 36 AC is really low. So that jumps out.

I pulled and tested every fuse in the block and all beeped back at me.

I took a look at the monitor as well. I have neck glow but I didn't feel any static. If it is there it is weak. I did not see any lights come on the chassis (or is this the deflection board in this case? apologies for my ignorance with vector). There is bank of (3) lights but they look nothing like the red LED light on the game board. None of the 3 lights came on.

There is one cap on the "chassis" (160v 47uf) that is obviously dying if not shot already.

So, I guess what jumps out at me (with my limited knowledge) is the AC voltage at the AR2 and the nasty cap on the chassis. I know I will need a cap kit. Do I also need a AR2 rebuild? Power supply rebuild?
 
The 36V AC must be measured between the two 36V test points in order to read properly. If you measure just from one of them to GND, you'll get the 18V that you're seeing, so that's normal.

Most of the other voltages look ok, except for the +22 being 14.22 on the AR. This is probably an error, as you say you're getting 23.82 on the aux board, and this is the same voltage, so it has to be ok on the AR. You might just have a dirty test point on the AR or something. Try measuring it on the leg of the large cap next to the test point, if so.

The 3 'lights' on the deflection board are neon tubes. They are safety mechanisms, which only light if something is really wrong on the deflection board, which almost never happens. So you can basically ignore them. (I've actually never seen a board with them lit, as they are really only a last-ditch safety thing, if the voltage on the deflection board goes too high, which doesn't ever really happen.)

If you aren't seeing the spot killer LED on the deflection board lit, it means either the deflection board is working, or it's so dead the spot killer isn't working at all. To check, watch the deflection board while you press and hold the reset button on the game board, for 2-3 seconds. You should see the spot killer LED on the deflection board turn on while the reset button is pressed, and then go off again when you let go of the reset button. If it isn't coming on at all, your deflection board has issues.

Do the Q500-502 and R100/101 mods to the deflection board either way. Test your frame transistors (see my 6100 guide below for how to do this, as the same procedure can be used on b/w vectors):

https://forums.arcade-museum.com/showthread.php?t=404600

Reflow the solder joints on all of the connector header pins for the deflection board. And let us know if there are any burned components on the deflection board. You want to get the deflection board working before worrying about the HV board, and the above should cover many of the common issues.
 
Also, if the deflection board is working, you should hear deflection 'chatter' while the game is playing blind, coming mostly from the yoke, as the deflection currents are flowing through it. The yoke wires vibrate, and give off a distinct noise. If you aren't hearing chatter, this also suggests the deflection board is not working.
 
i did the reset and i dont see thr LED coming on. I do see that some fuse holders on the deflection board are unused in what I have currently. F100 and F600 are both empty. is this the way it should be?
 
No. All fuse locations should be populated. If they're missing, it's probably because there are issues.

F100/101 are 5A slow blow. F600/700 are 2A normal blow. F102 is 1A slow blow.

Test your frame transistors, as well as the bridge rectifier on the deflection board (google how if needed). And check everything on the deflection board for cracked solder joints.
 
Pulled the whole monitor?

It comes out the front (which actually wasn't clear to me the first time I tried, lol). You just need to take the front off of the game. If you had it powered up recently, you should discharge the tube just to be safe, if you are going to remove the HV cage.

You don't need to discharge it to remove the monitor from the cab (and you physically can't do it easily anyway, while it's in the cab). But discharge if you're going to mess with the tube. And contrary to urban legend, you can discharge it with just a screwdriver and wire lead. And HV probe isn't needed to discharge (though you should have one to set it up, as you should measure and adjust the HV properly.)
 
Id rather not pull the whole frame and tube out. Can I test these frame transistors with it in place?
7028ebf13614b3b1dd0c5cbaa53ea149.jpg
 
Pulled the whole monitor?

It comes out the front (which actually wasn't clear to me the first time I tried, lol). You just need to take the front off of the game.

??????????????

If this is a BZ upright, the monitor comes out the rear of the game.
To analyze it correctly, the OP should remove the assembly and test on the bench.

BZ_MON_REMOVE.jpg
 
You can, but you really should remove the deflection board and inspect it for broken solder joints and wires too (which I think you can do without removing the whole monitor? Not sure if it'll fit through the opening in back, but I think it probably can.)

But you can probably test the transistors with it in the cab. Just be careful with the wires, as they like to break where they connect to the sockets on the frame.
 
I pulled the monitor to get at the HOTs and I pulled the deflection board from the shroud.

In looking over the deflection board nothing jumps out at me except the single cap that is gnarly.

3 of the 4 HOTs tested bad for me.

2 of them were identical (2N3792), another (2N3716) and the 4th (NTE284).

I also checked the remaining fuses on the deflection board and noticed that F100 was blown as well.

What is my next step?

Put in new HOTs, new fuses, hook it back up and see what happens?

If this is the case, I'm tempted to send my deflection board in to be looked over.
 
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If 3 of the frame transistors were identical, that could be part (or maybe all) of the issue, as one of them is wrong. There should be two 2N3716's, and two 2N3792's. The NTE might be a substitute for a 3792, but three 2716's definitely isn't right.

That said, it may have just blown the fuses, but it also could have damaged other active parts on the PCB. You should test all transistors on the deflection board with your DMM, looking for shorts between any of the 3 pins, and checking them using the 'two diode' method (google how to test transistors if needed).

If all of the transistors on the deflection board check out ok, you could try replacing everything, and firing it up. Worst case things will blow again, and parts on the PCB may burn up. In which case you can trade it in toward a rebuilt one (which I have).
 
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