Atari CX 5200 Field Service Manual page 139

CURSOR LEFT fRIGHT TROUBLESHOOTING
Is unit being supplied
with +5VDC?
Yes
Does TP5 toggle low
( OV) when the ball is
moved to right and high
( 5V) when the ball is
moved to the left?
Yes
Is TP7 low when the
ball is not in
m otion?
Yes
Is there a 5V square
wave at TP7 when the
ball is spun?
( Duty cycle will
vary with ball
speed).
Y es
Does an inverted TP7
signal appear at pin
A4
3 o f when the ball
is spun right and at
4 A4
pin of when the
ball is spun left?
No
A4.
Replace
Re'�urn to beginning of Test Sequence
CX5200 Field Service Manual
No
Replace game cable
assembly.
Are there 5V square
No
waves at T P l and T P 2
when the ball is spun?
No
Page 7 - 1 6
Is there a 5V
No
square wave at pin
4
of A3 when the
ball is spun?
Yes
Is there 5 V D C at
pin 3 of A 3 ?
Yes
S wapout A3.
Is there a square
wave at T P 7?
Yes
7 - 1 4
Return to beginning
of Test Sequence
A2
Replace
Yes
No
Page 7-1 7
No
Page 7 - 1 7
. Check C5 and R5.
No
Replace defective
components.