Sharp VT-G14 - Page 64

64
VT-G14
VT-G21
FLOWCHART NO. 2-4
TV TROUBLESHOOTING TABLE
NO RASTER
F1701 Check
Blown out
FLOWCHART NO. 2-5
NO PICTURE, NO SOUND
Normal
Replace the Fuse
T701 Pin (7)
voltage check
about: 350V DC
The Fuse is again
blown out
Normal
IC701 Check
+B voltage check
about: 115V
Normal
Normal
CRT connector
K3~K5 bias check
Abnormal
Normal
Normal
Abnormal
R701
Abnormal
IC701, IC751,
D710, D752
Normal
R604, R620,
Q601, Q602
IC801, Q801,
Q802, Q803
about: 0V
D752, Q751,
Q752
C1807, R603
D701, C704
Noise increases but
no signal is received.
Is there a signal at
pin (8) of IC401 ?
Picture noise
decrease but sound
level varies greatly.
Is there a signal at
pin (8) of IC301.
Is there a signal at
pin (1) of IC401 ?
Check IC401 and adjacent parts
NO NO
Is there a signal at
pin (47) of IC801 ?
Check IC801 and
adjacent parts.
Check IF Circuit and
tuner bias.
Check Tuner AGC.
R475, C481
NO
NO NO
NO
YES YES
YES
YES
YES
YES
YES
Check the
signal line
between
pin (3) of
IC351 and
pin (8) of
IC301.
Is there a
signal at
pin (3) of
IC351.
Is there a
signal at
pin (1) of
IC301 ?
NO
Check or
replace
IC351
and/or
adjacent
parts.
Is there a
signal at
pin (8) of
IC351 ?
Check
the
speaker.
Check
IC301
and
adjacent
parts.
Does the noise level increase at max,
Contrast, Brightness, and Sound Control ?
Abnormal
Normal
Check RF AGC
of IF Circuit.
Check IF
Circuit and
Tuner circuit.
Does the 6.6V (+B)
appear at pin (18) of
IC251 ?
Abnormal
Normal
Check the
D252, R289,
R290.
Check the
IC201 and
adjacent parts.
Check IC1001
Abnormal
Circuit to be checked:
1. TUNER
2. PIF
3. Automatic gain
control
4. 9V power source