Sharp MZ-80B - Page 27

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Trouble Shooting Chart
Problem (1)
The tape
does not run when the FF/REW button is pushed.
(Motor c:joesn't
rotate. 1
YES
l
Check r8el motor.
Check motor
voltage
I
Is +12V present
n
Check bu tton 1
between J3005- 7 r...r
switch n
l
9
NO
NO Check micro-switch
Check +5V, S.
Check~~F. REWJ
+12V, NS. +12V
AND STOP
button switches
(Solenoid doesn't
NO
Check level of f
NO
J3004-1.
Check har/le
work)
Check solenoid ~
av with tape inserted
voltage
Check Brake
I
5V with tape not in""ted~
Check le .... el of
NO
Does +12V appear'"
solenoid
CN3002~3
Check CPU board
YES
between J3005-3 YES
Does the av an d 5V
""'-4 and then +4V
level change when
Is level of J3003-111
the COunter linkage
magnet is turned
QV?
by hand.
YES
si
Check level'of
YE
IC3011
Problem (2)
Tape turns but, program cannot be recorded.
N~
Check CPU
board
Does a signal
N~
Check CPU
come from
I-
board
J3003~1 ?
y'E;
Is level of
f-
~
Check relay RY1.
J3003-5 OV?
Does a signal
Y'E;
appear at the
f-
recording head?
Y'E;'
Check recording head.
I
~-
Problem (3)
Tape turns, but programs cannot be played back or an error occurs.
NO
Check starting
r
position of
tape
Does a clean wave-
N,!?.
With a bad relay
form come from
f-
RYl, does the
J3003~2 ?
erase
head work?
Size of output
y'E;
voltage waveform f-
of 1/41C 3102.
~----
Low
Y'E;
Improper azimuth
adjustment of
record/playback
head.
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