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Jet Fighter *ATARI anno 1975* *Restoration*

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Thzarr:
Near the input: ~4.78vdc  ->  4.7vdc around the chips. 
All the switches got 4.75vdc except Coin and Slow" switch,  only 3,6vdc. 

Changed bypass cap 220u to 820u,  but that didnt boost the supply.

ChadTower:



I'm betting that is too low.  Try backing up to the transformer and work your way forward.


And check that edge connector again.  If it's burned off at the ground contacts the repair might not have been good enough.

Thzarr:
Its all in the jet fighter manual, detailed description.
I read it backwards and sideways trying to follow the path of starting process.

Sadly, Its not in original condition anymore. I cut the two main caps 2x8000uf and replaced it with a RIFA 10.000uf. Hoping it could be power failure.  No change.

Thzarr:
Long story short:
The first chip that activates the coincounter and startup procedure is located at F8.
With a wire I  poked at F8 inputs/output to fake HIGH or LOW signals to affect other chips.

GND-> F8 pin 1,2,3,4,5,6  (1,3) (2,4) (6)  Turned on the start buttons
Vcc .> F8 pins. -"-  Turned off the start buttons.

The low voltage on the coin switch got me thinking, its must be a short somewhere.
Where do the coinswitches get its voltage from, I couldn't find it.

1.st player joystick switches exl Fire and Right were failing.

I changed 100nf Y5V ceramics to 10uf elyt.
Still the same.

Thzarr:
 :banghead: :censored:

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