Atari Power Brick (Asteroids Deluxe) - Low voltage on J5, 1-3

Snakebee

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I am getting super low readings pin 1-3 on J5. The Big Blue has been replaced, the bridge rectifier seems to be good (.45 drop). Unless I've missed or read something incorrectly the problem seems to point towards the coil. I tested the lead of the orange wire before it connects to the rectifier as well as the orange wire before connecting to the F3 fuse and am only reading about 1.5vac. Am I barking up the wrong tree thinking this might be the issue?
 

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That's the 10.6 DC line. You should be reading those on DC scale, each point orange wire on Pin 1-3 to pins 5 or 6 (ground).

What is the status of F3? I have found fuse clips which are loose and high resistance, and connector issues with the fuse blocks. The fuse clips and connectors are tin, which corrodes resistive. Try cleaning those.

How are you measuring your voltage at Pin 1-3??
 
Pull, remove, and clean all fuses with fine sandpaper.

Inspect the fuse block to see if any of these slide on connectors are browned. If any are, pull them and clean the tabs with fine sandpaper.

Also, flipped the brick over, and see if any wires are heat damaged or corroded on the underside.
 
My mistake, I said I was measuring ac but I was actually measuring dc. I had the black lead on pin 5, red on 1-3.

The fuse(s) seems firmly in place. The fuse terminals don't seem to be too corodded. Same with the connectors at the rectifier. All the wires have continuity between the lug of the caps and 1-3.

Some of the wires are exposed from mice chewing. I thought I had taken care of all that but apparently missed some spot.

PXL_20250207_001039818.jpgPXL_20250207_001059387.jpgPXL_20250207_001106845.jpgPXL_20250207_001135615.jpgPXL_20250207_001217384.jpg
 
The chewed mouse wires need to be repaired. (Cut out the chewed parts and solder the good wires back together, then put shrink tubing over it.)

That one on the big blue cap is dangerously close to shorting against the chassis.

Also, where is the 4th connector on the bridge rectifier? (The black square thing.) There should be 4 wires connected to it, not 3.
 
What AC voltage are you getting from the transformer winding? Measured between the two orange wires that go to the bridge rectifier.
 
The chewed mouse wires need to be repaired. (Cut out the chewed parts and solder the good wires back together, then put shrink tubing over it.)

That one on the big blue cap is dangerously close to shorting against the chassis.

Also, where is the 4th connector on the bridge rectifier? (The black square thing.) There should be 4 wires connected to it, not 3.
I'll probably have to just outright replace those wires that have been chewed. There won't be enough to solder back together.

The 4th connector to the bridge rectifier was just left unplugged after I was testing it.
 
Fuse 3 powers the 10 VDC line. It isn't installed. You can get 10 VDC without that.
 
@ArcadeTechGW The fuse was installed when I was testing.

I found that the connectors coming off the transformer for F3 (orange) and F4 (yellow) were switched. 🤦‍♂️

Swapped them and now have about 14vdc on pins 1-3. @andrewb I did clean up the contacts and replaced the damaged wires though. 🙂

Thanks everyone!
 

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