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3-8
3. SERVO CIRCUIT
(1) Unstable Video in PB MODE
Unstable Video in
PB Mode.
Does the Noise level of the
screen change
periodically?
Do the CTL pulses appear
at the IC501 Pin8?
Is adjusting the height of
the CTL Head accurate?
Readjust the height of the
CTL Head.
Replace the IC501.
Refer to “When the Y signal
doesn’t appear on the
screen in PB Mode”.
Does the CFG waveform
appear at the IC501
Pin9?
On tracking do the CTL
pulses move?
Does the Video Envelope
waveform appear at the
IC501 Pin24?
Replace the IC501.
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
(2) When the Drum Motor
(2)
doesn’t run.
Do the DFG Pulses appear
at the PMC01 Pin11?
Replace the Cap M.
Aren’t the foil patterns and
the Components between
IC501 Pin104 and PMC01
Pin11 short?
Replace the IC501.
Refer to “(2)
No 12VA of Power section”
Do the Drum PWM Pulses
appear at the IC501
Pin107?
Aren’t the foil patterns and
the Components between
IC501 Pin107 and PMC01
Pin12 short?
Do the DFG Pulses appear
at the IC501 Pin104?
Do the Drum PWM Pulses
appear at the IC501
Pin107?
Aren’t the connecting patterns and the Components
between IC501 Pin107 and PMC01 Pin12 short?
When the Drum Motor
doesn’t run,
Does 12V appear at the
PMC01 Pin8?
Does 2.8V appear at the
PMC01 Pin12?
Check the connector
(PMC01) and the Drum
Motor Ass’y.
NO
YES
YES
YES
NO
NO
NO
NO
NO
YES
YES
YES
Summary of Contents for DVP 721VR
Page 36: ...3 32 3 33 2 POWER SMPS CIRCUIT DIAGRAM 2 ...
Page 37: ...3 34 3 35 3 TU IF NICAM A2 CIRCUIT DIAGRAM EE MODE VIDEO TU MODE AUDIO ...
Page 40: ...3 40 3 41 6 SCART JACK CIRCUIT DIAGRAM ...
Page 45: ...3 50 3 51 PRINTED CIRCUIT DIAGRAMS 1 MAIN P C BOARD VCR DVD _SOLDER SIDE LOCATION GUIDE ...
Page 46: ...3 52 3 53 2 MAIN P C BOARD VCR DVD _COMPONENT SIDE LOCATION GUIDE ...
Page 60: ...3 68 F FE RFL FIG 7 2 DVD F FE RFL FIG 7 3 CD ...
Page 61: ...3 69 F FE RFL FIG 7 4 CD 8 FOCUS ON WAVEFORM FE FOSO F F FIG 8 1 DVD ...
Page 65: ...3 73 13 MT1389 AUDIO OUTPUT TO AUDIO DAC 2 COMPOSITE VIDEO SIGNAL FIG 12 2 FIG 13 1 ...
Page 66: ...3 74 FIG 14 1 14 AUDIO OUTPUT FROM AUDIO DAC ...
Page 71: ......
Page 72: ...3 79 3 80 CIRCUIT DIAGRAMS 1 SYSTEM CIRCUIT DIAGRAM ...
Page 73: ...3 81 3 82 2 RF DSP SERVO CIRCUIT DIAGRAM ...
Page 74: ...3 83 3 84 3 AV JACK CIRCUIT DIAGRAM ...
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Page 113: ......
Page 115: ......