G05 805, no High voltage

Mark Hooks

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I recapped my asteroids mini cabret monitor with a Bob Roberts kit, but the screen is still dark. I also reflowed all the solder joints.

I don't hear any high voltage crackle on power up and I do have a bright heater element. I lalso hear good defelection "chatter" It plays blind. The high voltage side doesn't have any burnt or obviously damaged parts. Any ideas what would cause this?

I bought the game with a dead monitor, and I'd really like to get it going again. I am sooo close...

Mark Hooks
 
Spot killer LED is off?
Fuse F102 is good?
Bridge rectifier DB100 tests as good?
Diode D100 tests as good?
Check voltages at the HV connector? (pin 3 +400, pin 5 +90, pin 8 +40)
Did you replace the pots on the deflection board?

I recapped my asteroids mini cabret monitor with a Bob Roberts kit, but the screen is still dark. I also reflowed all the solder joints.

I don't hear any high voltage crackle on power up and I do have a bright heater element. I lalso hear good defelection "chatter" It plays blind. The high voltage side doesn't have any burnt or obviously damaged parts. Any ideas what would cause this?

I bought the game with a dead monitor, and I'd really like to get it going again. I am sooo close...

Mark Hooks
 
Spot killer LED is off?
Fuse F102 is good?
Bridge rectifier DB100 tests as good?
Diode D100 tests as good?
Check voltages at the HV connector? (pin 3 +400, pin 5 +90, pin 8 +40)
Did you replace the pots on the deflection board?

Thanks, I do know that:

Spot killer is off
F102 is good
Still need to check the DB100
HV connector readings: DEAD ZEROs
Didn't find replacement pots in the Bob Roberts kit, although the old ones look good. I tried adijusting them with no change.

What do the zeros on the HV input indicate?
 
Update:

D100 and DB 100 are good. Pin 8 has the correct voltage, but the 90 volts at pin 9 is at zero. The 300 volts is missing too. Are these voltages generated on the deflection board or the high voltage board?

Mark

Thanks, I do know that:

Spot killer is off
F102 is good
Still need to check the DB100
HV connector readings: DEAD ZEROs
Didn't find replacement pots in the Bob Roberts kit, although the old ones look good. I tried adijusting them with no change.

What do the zeros on the HV input indicate?
 
I just checked the flyback with a ring tester and it appears the primary winding is shorted.

Update:

D100 and DB 100 are good. Pin 8 has the correct voltage, but the 90 volts at pin 9 is at zero. The 300 volts is missing too. Are these voltages generated on the deflection board or the high voltage board?

Mark
 
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