Battlezone/ G05-802 plays blind

Zinfer

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Recently had the PCB repaired. Plugged her in and the game is playing blind. No video. Ran a couple lines from X and Y out to my oscilloscope and I do have a good signal.
The spot killer is off, Good neck glow, deflection chatter - but no video? Changed out the HV diode for a brand new one. Same results. It all should be working, but it's not.
Is it possible for the flyback transformer to be bad? I'm not hearing any crackle or anything to the screen of the tube at all.
 
I had the same problem and couldn't figure it out. I spent 3 days working on it a couple of hours each day. Finally i just put in the Battlezone high score kit that i had, once installed it worked perfect! So i assume i had a board problem but had the same problems you did and changed out the hv diode as well.

hope this helps, good luck...

Recently had the PCB repaired. Plugged her in and the game is playing blind. No video. Ran a couple lines from X and Y out to my oscilloscope and I do have a good signal.
The spot killer is off, Good neck glow, deflection chatter - but no video? Changed out the HV diode for a brand new one. Same results. It all should be working, but it's not.
Is it possible for the flyback transformer to be bad? I'm not hearing any crackle or anything to the screen of the tube at all.
 
I assume you've adjusted the brightness, and contrast knobs?

Check R100 R101 for Open

Double check all the fuses.

It's not uncommon to not hear static when you turn the monitor on, especially if it was just recently turned on. You could turn it on, then off, and discharge the tube. If you get a spark then it was charged. Not the best way to test for HV.

I use a HV probe to set mine up.

Also re-flow all the connector header pins.
 
Yea I definitely checked the brightness and contrast first.
Fuses all check out fine.
I haven't gotten a spark yet on tube discharge. Although I'm hesitant to do it again with a new HV diode in there now. I'll need to pickup one of those discharge tools.
Haven't reflowed any pins yet.
R100 and R101 are not present. But I didn't pay any attention to them not being there as I thought those were unnecessary.

Braido, I'm getting X and Y out signals on the scope, so video out is good. The problem has to be in the HV or deflection board. If I wasn't getting any X or Y signals my spot killer would be on.
 

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From your picture I don't see any wire where R100, 101 used to be. Make sure there is a wire shorting where they used to be on the back side.
 
field fix was to replace the resistors with a wire

factory fix added a trace on the solder side

pretty sure not having the resistor or wire would activate the spot killer (but I'm not a monitor expert)
 
w8, w9, w10, w11 are jumpered to provide a path so it looks like it's a post revision 5 board.
HALP!
 
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That, I think is my next step. But I've never had a cap kit FIX no video. Could always be a first time I suppose. I'll put in an order for a cap kit today, but - let me get an opinion here:
I've had the worst problems with replacing the frame mounted transistors on my Asteroids. Do you think it'd be wise to just go with a straight cap kit without transistors, or in for a penny in for a pound? I just hate messing with them. I was going to go for a cap kit minus the transistors as they are a complete PITA. And the cap kit is less than half the price without them. I could buy two cap kits for the price of one with transistors.
 
Well I reflowed all the headers on the deflection board. No result. I'll try reflowing the HV connector header. Seems like the tube's not getting any charge AT ALL.
I'm not sure what can cause that.
I did read up on the B&W faq and tried to find something that matched my experience in the troubleshooting section but closest I could find was
Symptom: Game Plays Blind With Deflection Chatter.
If you can hear deflection chatter, and the game plays "blind", then there are two things you must
check: (1) Low / no voltage to the tube filament; and (2) A failure in the HV supply.

The necktube is glowing. As far as the HV supply. That's kind of generic and doesn't go into detail on where to check voltages at.
 
Ok, thanks for that. That was very helpful and informative.
My sixth grade teacher used to answer similarly with 'Read the book'. I'm thinking it's because he had no idea, but it was a smart way for him to say it. :)
But to be quite honest, I don't wish to learn by practice on the HV section.
 
Update: replaced all 4 frame transistors. Curious, a pair of the old ones were 2N5876's where the 2N3792's would normally go at Q609 and Q709.
Also reflowed HV connector that leads to the deflection board. No luck.
 
If you have anything more to say please utilize PM for it.

It could also be that your teacher did not want to spoon feed you the answers because it would put you in the situation you are in now. You want someone to spoon feed you the solution when all the answers are documented right in front of you. Problem is you haven't even provided enough information to spoon feed you the answer this time. Without voltage checks, there is absolutely no way for anyone to know what is specifically wrong with your monitor.
 
The bottle cap Frame transistor are for deflection. So if you're missing HV. I would not suspect that being the problem. It may be a bad cap if it is no longer functioning. It could also be one of the transistors on the HV unit. There is others with more knowledge then me out there. So keep us posted on your progress.
 
Yep. I was just surprised to see those 2N5876's. Ordering a cap kit for it now. I like to start with the basics before getting into the thick of it. Not a bad idea replacing the transistors on the HV pcb.

The bottle cap Frame transistor are for deflection. So if you're missing HV. I would not suspect that being the problem. It may be a bad cap if it is no longer functioning. It could also be one of the transistors on the HV unit. There is others with more knowledge then me out there. So keep us posted on your progress.
 
I think he was objecting to the way you were speaking to him. It's like you think he's an idiot, and not a newbie.

There's no need to offend people here. If you don't want to help, then don't.

SOME of the language in those FAQs is difficult for a newbie to understand 100%
 
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