[Solved] Need help with Asteroids Deluxe PCB - resets every 5 seconds

[banane]

Measure the voltages on the X and Y test points and report what the Min and Max voltages are.

On the test screen:

• X OUT lowest gain 2,1VAC - highest gain 7,4VAC
• Y OUT lowest gain 1,6VAC - highest gain 6,2VAC

I put out the deflection board to have a look at it, put out the four external transistors ... switched it on again.

First just to take a photo of the oscilloscope:


Then I switched on the monitor again - woah, picture:



But the points where the lines meet are distorted.
Hmmm, starting searching the internet (e.g. this forum) for this symptom now ...

EDIT: e.g. https://forums.arcade-museum.com/threads/asteroids-graphics-glitch-any-ideas.522242/

 

[wugly]

the squiggle is a problem in the analog section. can't remember off the top of my head if its the dac or the tl082 that comes after it. think its the dac. busy at moment getting things ready

 

[Arcadenut]

You only replaced one of the TL082, so it's possible the other one has an issue too.

 

[banane]

I just ordered a few TL081, TL082 and 4016 from a reliable source (Reichelt in Germany). Thank you all first of all, this was very helpful and I'm almost there

 

[banane]

Replacing both CD4016BE in the vector output circuit solved the problem with the squiggle.

Thank you all so much for your help .

Will mark this thread as solved now.

 

[Arcadenut]

Awesome!

 

[VectorCollector]

Spectacular!