Bright dots and errant lines on an Asteroids Delux dedicated

[Pipercub]

I just moved and aside of minor issues here and there with a few other machines my Asteroids is having a big problem. When powered up there is a single bright dot in the center of the screen and several dots at the edges of the letters and graphics which are connected by phantom lines that should not be there. I checked for any damage, cleaned and re-seated all connectors and no change. Looks to me like X or Y is out, probaby on power up and just a coincidence with the move. Anyone have any tips tricks etc. for this?

[JB]

Try turning the brightness down. It sounds like the brightness is high enough that it's drawing even when the vector beam is "turned off."

[Pipercub]

I will try that when I get home in the morning, although I doubt that is it because the game worked 100% before moving and did this on power up and the back never came off the machine, pots normally don't just change themselves. In reading the schematic notes ( I have all the manuals and schematics) it does mention a function to turn off the beam between drawing lines and that sure seems like what is not happening. Of course they give no further information and go into a long rambeling about the numerical range of the X and Y coordinates. Another post mentioned that they saw the same problem with a failed power supply to the monitor, I will have to check those values too.

[ChadTower]

You opened cold solder joints in the move, probably.  These 20+ year old games do that when you move them.  Seems to be the monitor.  A vector monitor has a spot killer circuit in it.  When the X or Y or Z is out, the spot killer goes on.  The spot killer prevents a malformed signal from destroying the tube.  If X, Y, or Z were below spec (12v to -12v for x and y, I forget the range for Z), the monitor would just shut down.  As such, your problem is probably in the monitor chassis itself.

When was the last time this sucker had a cap kit?

[Pipercub]

Just got one as I figure I will have to pull the monitor at some point and if I have to do that I may as well cap kit it. I just did a Bob-roberts power supply rebuild to fix a hum that had developed (about a year ago) so I am fairly confident that section is Ok. The spot killer is not triggering as there is a display (and spots) as well as the LED not being lit. Out of 15 machines one failure isn't so bad, it took me about 2 hours to get all the others powered up and working, a bulb here, a connector there and such.

[ChadTower]

When was the power supply filter cap replaced?  If that's bad, it can really reduce the life of other parts.