Atari Asteroids Deluxe Cocktail / G05-805 Problems

Fynflood

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Picked this up last year and just now getting around to working on it. The G05 has neck glow, but no image (no dot, nothing. Red LED is lit).
I pulled the monitor and reflowed all the connectors - was obvious they desperately needed it, and replaced F100 and F101 on the deflection board and gave it a go.

Right away R25 (10ohm resistor) on the AR1 started smoking, led on the PCB did not come on. Remove the G05, and all is well again.

Not sure what which direction to look at next here. The AR1 seems fine - voltage is good and works fine when the G05 is out of the equation.
 
are any of the G05 fuses blown? I don't know what an R25 goes to, Atari games aren't my area of expertise but I've had to fix a few vector monitors over the years.

if you have the game board dipswitches set for free play, did the start buttons flash? if not then the game wasn't running and running a vector monitor without good XY signals is akin to running a car engine without oil. lol

@andrewb should have more useful advice for you in time
 
are any of the G05 fuses blown? I don't know what an R25 goes to, Atari games aren't my area of expertise but I've had to fix a few vector monitors over the years.

if you have the game board dipswitches set for free play, did the start buttons flash? if not then the game wasn't running and running a vector monitor without good XY signals is akin to running a car engine without oil. lol

@andrewb should have more useful advice for you in time
Yeah F100 and F101 were blown. R25 is on the audio board, which is why I'm confused.

The game plays fine blind - hooked my scope up to it and it looks great.
 
Yeah F100 and F101 were blown. R25 is on the audio board, which is why I'm confused.

The game plays fine blind - hooked my scope up to it and it looks great.
ok then you probably have a bad bridge rectifier on the deflection board. I'm certain the F100 and F101 fuses go to either of the AC input sides to that. I can't exactly visualize it now cause I've been into a lot of not-vector things this year. lol I could just look at schematics though. but I've seen the bridge rectifiers go bad on B&W vector monitors a few times.

EDIT: DB100 is the bridge rectifier, I was right F100 and F101 go to the AC inputs to it.

db100.png
 
I figured since I had it out, I'd recap it, so I did that. The rectifier tested ok, and I don't have one on hand. Plugged it back in, and have some progress!
Now, this was with the brightness all the way up, which probably isn't ideal - but stoked to see _something_.

Seeing half the screen was collapsed, I went ahead and replaced all 4 power transistors, but that didn't fix anything (they seemed to test alright, but one was on the low end, so I just did all 4)

Triple checked the connectors, all seem fine.

So, is the the X or Y side that jacked? Sorting that always confuses me :cautious:
1750559266899.png
 
After reading a bunch of Andrew's older posts on the subject, I went back and fussed with the connectors again. It worked for a bit, but after powering off and on again, I lost the bottom half. Looks like I'll be taking a closer look at them!

But, it is very dim. Playable in the dark only... I'd thought recapping and replacing the power transistors would have brightened it up a little, but no luck.

1750561670465.png
 
If you have not already done so, reflow ALL the header connections on the Deflection Board - and look for them elsewhere as well. After all the years of use, thermal cycling, and plugging / unplugging connectors, it's guaranteed there will be cold solder joints.
 
If you have not already done so, reflow ALL the header connections on the Deflection Board - and look for them elsewhere as well. After all the years of use, thermal cycling, and plugging / unplugging connectors, it's guaranteed there will be cold solder joints.
That was the very first thing I did! I think I'll probably reflow the whole board. When I did the connectors, disconnecting the back one, the whole thing came off :LOL:
 
It may be the HV diode. Those are notorious for getting rusted springs, and as it heats up, the screen gets dimmer and dimmer.

andrewB has some threads on how he repairs them. Discharge, remove the anode from the tube and then carefully remove the diode from the cups, clean everything with q-tips and some solvent cleaner, solder the springs to the fuse. Find one of the threads on the subject.
 
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If the pins are heavily oxidized, it will be necessary to add fresh solder to get any kind of wetting action. But, don't stop there - remove all the solder you just applied (old &new), and clean the pins carefully with a soft brass brush. The solder will only wet properly when the oxide layer has been removed from each pin. Once the pins have been brushed and the oxide layer removed, reflow with fresh solder.

Also - check carefully for cracked or broken traces. When you get a full image once or twice, and then it inexplicably collapses again - especially after cooling off - it is most likely a case of residual cold solder joints or cracked traces.

Do you have access to a CRT tester / rejuvenator? I recently worked on a Stunt Cycle 19V2000 (19VARP4 tube) that was extremely dim and had poor focus in the corners. A restore with my Sencore CR70 was partially successful, but ultimately, I had to perform one rejuvenation cycle - and the tube responded nicely. The point being that the cathode might be heavily fouled and the emission is low - resulting in reduced brightness.

@ArcadeTechGW also brings up a good point with the HV diode - so that is worth checking as well.
 
Ok - pulled the connectors again and cleaned them up with a dremel. Nice and shiny, and a bit of flux. Cleaned up the pads with a fiberglass pen, thin coat of flux and resoldered. This seems to have worked well!

I also pulled the HV diode while I had it out, and gave that a good cleaning best I could. The boots are very solid at this point in their lives, so I was worried about them being brittle. I didn't force the springs out but flushed everything out and gave it the best scrub I could. Slapped everything back in, and it's not bad. I don't think I really got a noticeable brightness increase, but after warming up at least I can see it with the lights on, and it looks pretty great in the dark. I do have a spare diode I might test next time it's out.

That said, I am now seeing a little wiggle in lines.

1750616124923.png
1750616148426.png
 
Glad to hear you are making progress. I can't tell if that's rust on the diode spring, or well-aged dielectric grease. Removing the dried grease residue and soaking the springs in vinegar to remove the rust would be preferable. The goal is to minimize the resistive losses between the cups, springs and diode leads - thereby minimizing ohmic heating . Are you able to adjust the brightness and contrast pots to improve the appearance with higher levels of ambient light?

The wiggles could well be a dirty potentiometer. If you haven't already done so, applying DeoxIT D5 to the pots, making sure it gets to the wiper and track, and working them back and forth a few times might be all that is required.
 
Glad to hear you are making progress. I can't tell if that's rust on the diode spring, or well-aged dielectric grease. Removing the dried grease residue and soaking the springs in vinegar to remove the rust would be preferable. The goal is to minimize the resistive losses between the cups, springs and diode leads - thereby minimizing ohmic heating . Are you able to adjust the brightness and contrast pots to improve the appearance with higher levels of ambient light?

The wiggles could well be a dirty potentiometer. If you haven't already done so, applying DeoxIT D5 to the pots, making sure it gets to the wiper and track, and working them back and forth a few times might be all that is required.
This seems to have done the trick, or at least minimized it to an acceptable level. Can't really see it in game anymore - slightly obvious in test mode, but significantly better.

@mecha Noted. Next time it's out I'll yoink'em. Thanks!
 
Late to the party (as I'm usually not around here on weekends). But a few things:

- The resistor smoking on the AR is due to a bad connection between the AR and game board, most likely at the edge connector. This is common on these games. Clean your edge connector with a fiberglass pen and DeOxit. This isn't optional, it's a must do for any Atari game, to prevent future power problems. Also apply DeOxit to all Molex connectors in the cabinet, especially the ones on the AR. Here's what you need:

https://www.ebay.com/itm/201067762269 (Fiberglass brush)
https://www.ebay.com/itm/306144854777 (DeOxit)

- Loss of half of the screen, with no blown fuses, means there's a cracked or bad connection to whichever one of the frame transistors controls that axis and half. This can happen at the header joints, header traces, or a break in the wiring to/from the frame transistor, and also a loose transistor socket. It looks like you found it, but FYI, you want to actually find these issues, not just guess. That way you know you really found and fixed the problem, as a lot of problems (especially intermittent ones) can come and go simply from handling the board. Also, the transistors you replaced on the deflection board are still fine, I hope you saved them, as they're like $5 each these days. You can always use them as spares.

- The HV diode had nothing to do with your issue here. When the HV diode has problems, you get blooming (or just no picture), not brightness problems. You disassembled the diode, but be aware that all that crap inside the boots needs to be cleaned out. I also solder the springs (springs, not the wires) to the diode, then put the diode back in the boots. It's critical to do this correctly, otherwise the diode and boots will burn up again.

The way to test this is to run the monitor for ten minutes, power down, discharge the CRT, then feel the diode with the back of your finger. It should be cool to the touch. If it isn't, that usually means one or both of the connections to the diode is not solid, and has enough resistance to generate heat. (Or it can mean the diode is bad in some cases, but that's not usually the case.)

Note that I have a longer post about doing the diode cleaning here:

 
Late to the party (as I'm usually not around here on weekends). But a few things:

- The resistor smoking on the AR is due to a bad connection between the AR and game board, most likely at the edge connector. This is common on these games. Clean your edge connector with a fiberglass pen and DeOxit. This isn't optional, it's a must do for any Atari game, to prevent future power problems. Also apply DeOxit to all Molex connectors in the cabinet, especially the ones on the AR. Here's what you need:

https://www.ebay.com/itm/201067762269 (Fiberglass brush)
https://www.ebay.com/itm/306144854777 (DeOxit)

- Loss of half of the screen, with no blown fuses, means there's a cracked or bad connection to whichever one of the frame transistors controls that axis and half. This can happen at the header joints, header traces, or a break in the wiring to/from the frame transistor, and also a loose transistor socket. It looks like you found it, but FYI, you want to actually find these issues, not just guess. That way you know you really found and fixed the problem, as a lot of problems (especially intermittent ones) can come and go simply from handling the board. Also, the transistors you replaced on the deflection board are still fine, I hope you saved them, as they're like $5 each these days. You can always use them as spares.

- The HV diode had nothing to do with your issue here. When the HV diode has problems, you get blooming (or just no picture), not brightness problems. You disassembled the diode, but be aware that all that crap inside the boots needs to be cleaned out. I also solder the springs (springs, not the wires) to the diode, then put the diode back in the boots. It's critical to do this correctly, otherwise the diode and boots will burn up again.

The way to test this is to run the monitor for ten minutes, power down, discharge the CRT, then feel the diode with the back of your finger. It should be cool to the touch. If it isn't, that usually means one or both of the connections to the diode is not solid, and has enough resistance to generate heat. (Or it can mean the diode is bad in some cases, but that's not usually the case.)

Note that I have a longer post about doing the diode cleaning here:


Thanks man!

Will clean all connectors for sure - Very familiar with DeOxit, it's been a staple in my garage even before the arcade times. Brilliant stuff!
Transistors saved for sure!
I'd found you post on the HV diode - it was also _very_ helpful. I did clean the boots as well.

Any pointers on the brightness? Just a tired tube perhaps? After it warms up for 5min, it's playable - but the pot is maxed out and that doesn't sit with me too well.
 
Could be something on the deflection board, in the Z axis. Could also be a weak tube, but that's usually not the case. And you'd want to rule out all other possibilities before trying to rejuve the tube, since rejuving is a destructive process, and should only be done as a last resort.

The tube's heater is powered by the 6.3V AC that comes from the brick (which is the same voltage that powers the coin door bulbs). If that's weak from a bad connection somewhere, that will cause a dim picture. Clean and DeOxit all connections in the 6.3V path between the brick and the tube. (Brick, main monitor connector, long connector on the side of the deflection board, and the tube socket.) The tube socket in particular is important, as they can get loose and dirty, and cause dimness. You should also pull the neck socket off and clean the tube pins (carefully) with the fiberglass pen, and DeOxit them.

Also, it was mentioned above, but if your deflection board still has the R100/101 big white power resistors, those should be removed and jumpered. Also, if you do have them, replace Q500/501/502, as these can also cause dimness issues. See this post, and the thread it references:


Also, do you have both the brightness AND contrast pots maxed out? Or just brightness? They work together, and both need to be adjusted to get the best picture. But with the brightness maxed, do you see the retrace lines *and* still have a dim image if the contrast is maxed as well?
 
Also, do you have both the brightness AND contrast pots maxed out? Or just brightness? They work together, and both need to be adjusted to get the best picture. But with the brightness maxed, do you see the retrace lines *and* still have a dim image if the contrast is maxed as well?

Only the Brightness is maxed, but the Contrast is pretty close. I've got it backed off a little to make the picture look as intended (dimmer asteroids, bright shots and ufo, etc). I cannot get it to show me retrace lines at all.
 
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