Defender resetting with ram & rom failures. Starting from the beginning.
I have the later set of boards.
This board set "does have the 4164 ram mod & battery mod".
The boards are fresh back from repair but doing the same stuff as when they were sent.
I have never worked on a defender before. I am also but a padawan learning to read the schematics correctly. I don't want to just go hap haphazardly trying to test stuff until I am sure I am doing it right.
Anyway I wanted to start from the beginning on this defender and make sure I have a rock solid linear power supply. This is what I gleaned from a set of schematics.
Are these TP values correct for this power supply?
----
TP1 5.1 VDC
TP2 +12.8 VDC
TP3 -14.8 VDC
TP4 +12.1 VDC
TP5 -4.9 VDC
TP6 Ground
Did I read it right? What are all the necessary steps to testing this defender power supply correctly?
Oh better snaps...
----
http://arcadeparts.org/Machines/Williams/Defender/Boards/
Thanks for all your help!
I have the later set of boards.
This board set "does have the 4164 ram mod & battery mod".
The boards are fresh back from repair but doing the same stuff as when they were sent.
I have never worked on a defender before. I am also but a padawan learning to read the schematics correctly. I don't want to just go hap haphazardly trying to test stuff until I am sure I am doing it right.
Anyway I wanted to start from the beginning on this defender and make sure I have a rock solid linear power supply. This is what I gleaned from a set of schematics.
Are these TP values correct for this power supply?
----
TP1 5.1 VDC
TP2 +12.8 VDC
TP3 -14.8 VDC
TP4 +12.1 VDC
TP5 -4.9 VDC
TP6 Ground
Did I read it right? What are all the necessary steps to testing this defender power supply correctly?
Oh better snaps...
----
http://arcadeparts.org/Machines/Williams/Defender/Boards/
Thanks for all your help!
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