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PV-9661 / PV-9662
Note:
Be careful not to let the DC Power Supply Unit GND
contact the chassis GND. This may damage the
Loading Motor Drive IC (IC 2501).
Be sure to apply DC + to Portion "a" of Motor P.C.B.
If DC + is applied to Portion "b", the Loading Motor Drive
IC (IC2501) may be damaged.
3. Rewind the tape into the cassette by turning the Center
Clutch Unit counterclockwise.
4. Eject the cassette by applying +10.0VDC Power Supply
again.
5. After completing the removal procedure, solder Portion "a"
and Portion "b."
4.1.8.
DEFEATING THE AUTO TRACKING
To defeat the Auto Tracking Function, place the instrument in
the STOP mode and place a jumper between TP6003 and
TP6009 on the Main C.B.A. The tracking will be placed in the
neutral position.
4.1.9.
HOW TO SET TRACKING TO THE
NEUTRAL POSITION
Ejecting the cassette tape and then reinserting it will reset the
tracking to the Neutral position.
4.1.10. CYLINDER ROTATION IN STOP
MODE
The cylinder will continue to rotate for approximately 5 minutes
after the STOP button is pressed in Play mode etc. Eject the
tape in order to stop the cylinder.
4.1.11. BLACK SCREWS ON THE
CHASSIS
Black Screws are used on the Mechanism Chassis to identify
screws that require adjustment.
4.1.12. HOW TO RESET ALL VCR
MEMORY FUNCTIONS
To reset (clear) the select language, channel auto set and set
clock functions to their initial power on condition (power on, no
cassette inserted), hold down the PLAY and CH UP buttons on
the unit together for more than 5 seconds. Power will shut off.
Fig. 7
4.1.13. VARIABLE VOLTAGE ISOLATION
TRANSFORMER
An Isolation Transformer should always be used during the
servicing of VCR whose chassis is not isolated from the AC
power line. Use a transformer of adequate power rating as this
protects the technician from accidents resulting in personal
injury from electrical shocks. It will also protect VCR from being
damaged by accidental shorting that may occur during
servicing.
Also, when troubleshooting the above type of Power Supply
Circuit, a variable isolation transformer is required in order to
increase the input voltage slowly.
4.1.14. SPECIAL NOTE
All integrated circuits and many other semiconductor devices
are electrostatically sensitive and therefore require the special
handling techniques.
4.1.15. REPLACEMENT PROCEDURE FOR
LEADLESS (CHIP) COMPONENTS
The
following
procedures
replacement of the leadless components used in this unit.
1. Preparation for replacement
a. Soldering Iron
Use a pencil-type soldering iron that uses less than 30
watts.
b. Solder
Eutectic Solder (Tin 63%, Lead 37%) is recommended.
c. Soldering time
Do not apply heat for more than 4 seconds.
d. Preheating
Leadless
capacitor
installation. -(266°F ~ 302°F)
(130°C ~150°C) for about two minutes.
Note:
a. Leadless components must not be reused after
removal.
b. Excessive mechanical stress and rubbing of the
component electrode must be avoided.
2. Removing the leadless component
Grasp the leadless component body with tweezers and
alternately apply heat to both electrodes. When the solder
on both electrodes is melted, remove the leadless
component with a twisting motion.
Note:
a. Do not attempt to lift the component off the board until
the component is completely disconnected from the
board by a twisting action.
b. Be careful not to break the copper foil on the printed
circuit board.
16
are
recommended
for
must
be
preheated
before
the
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