G05-802 Help needed!

DrEvil

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So I have 3 G05 monitors. I have been swapping parts all night. All voltages on the HV box are present, no spot killer, Asteroids plays blind, and no blown fuses.

Here is what I am getting:

12%2B-%2B1
 
Check the focus pin on the tube, the focus wire to the socket, the deflection wiring to the yoke, and anything around a focus control...
 
I have seen that when I mixed up the placement of the legs on a deflection board transistors - EBC instead of CBE or the other way around.
 
I have not done the caps yet.. I will do them when I get to my office in a few.

Focus is getting about 110 volts in the HV box, does not change when adjusting focus control. All of the Transistors on the Chassis are new, and not grounded to the chassis.

I have tried 3 different yokes... and a seperate HV box. No change.
 
Update...

I changed out the 2n3716 closest to the rear of the chassis and I now get a small line on the very top of the monitor. The white blob has now changed as well....

here are some pics:

12+-+1

12+-+1
 
Have you tried playing with the X Y pots on the board. You might be able to move that image around and figure our which section (X or Y) is causing your problem.
 
Have you tried playing with the X Y pots on the board. You might be able to move that image around and figure our which section (X or Y) is causing your problem.
yes. It does move the picture however I think the problem is on the deflection board.
 
yes. It does move the picture however I think the problem is on the deflection board.

Yeah, it is definitely a deflection board problem and not a board issue, but you may be able to move the picture around to help you ID which part of the deflection board is giving you the problem.
 
So now I figured out that the blur on the screen is a dot that I can move by rotating the yoke. I can move it anywhere on the screen, but nothing changes. It seems that the dot will get slightly larger and smaller, almost like the entire screen image is super compressed.

I have adjusted the pots to no avail, and even put in another DB that will replicate the exact same problem. I don't think it's the tube, but I have 2 more to choose from so I might try that next.

Any other thoughts? Would a video help?
 
Have you replaced the bottlecap transistors on the frame? If you have I would then test the four transistors that are mounted on heatsinks on the D-board. Have you reflowed all the header pins on the D-board?
 
Have you replaced the bottlecap transistors on the frame? If you have I would then test the four transistors that are mounted on heatsinks on the D-board. Have you reflowed all the header pins on the D-board?

Yes to both.

I replaced the 2 large caps and removed and jumped the resistors... I also reflowed all solder joints. Now spot killer is on and dot is still on screen with full brightness.
 
Are you sure your game board is working? If another deflection board does the same thing, that makes me suspect the game. If you set your meter on AC voltage and measure the X out, Y out and Z out see what you get - zero means bad game board output.

I'd also turn down the brightness until you get it sorted out!

Note that there are different revisions of the G05 deflection board, and have different pinouts at the keyed connector of P100. If you're swapping boards make sure they're the same rev.

See the B&W vector monitor FAQ if you haven't already.
 
Are you sure your game board is working? If another deflection board does the same thing, that makes me suspect the game. If you set your meter on AC voltage and measure the X out, Y out and Z out see what you get - zero means bad game board output.

I'd also turn down the brightness until you get it sorted out!

Note that there are different revisions of the G05 deflection board, and have different pinouts at the keyed connector of P100. If you're swapping boards make sure they're the same rev.

See the B&W vector monitor FAQ if you haven't already.

I have not metered the board, however it does play blind.

Until I replaced the 2 large caps and resoldered all points on the d-board, I had no spot killer light on. I will meter the x/y and see what I get from there. I do have 2 game boards but one is in reset right now and wont boot (flashing p1/2 lamps)

I did order a full cap kit and new x-istors from Bob Rob.

They should be in tomorrows mail....

Thanks for the suggestions so far. Hopefully I can get this out of my basement and back to its owner!
 
Double check the Molex connector where the monitor connects to the main harness. Maybe a pin has been pushed out of place in the Molex connector and is not making contact. I've seen that do some weird stuff that took me a while to track down.
 
Molex is good, game board has voltage.. although its DC and not AC should this be a concern? Cap kit and new transistors going in this weekend so will have more to go on soon.
 
If your X and Y outputs are putting out DC only, that's bad. Playing blind means the game logic and sounds are working (which is good) but the complementary analog section of the board that takes the data from the vector generator and turns it into varying voltage to indicate where the beam should move around the face of the monitor is not working. The deflection board of the monitor takes the X and Y voltage from the game board, 'amplifies' it and sends proportional current to the deflection coils in the yoke that actually alter the path of the beam. If the XY voltage isn't alternating then the beam doesn't move.
 
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