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counterclockwise.
5. Eject the cassette by applying+10.0 V DC Power Supply again.
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, nocassette inserted), hold down the PLAY and CH UP buttons on
the unit togetherfor more than 5 seconds.
Power will shut off.
4.1.13. HOW TO CONFIRM AUTO CLOCK SET FEATURE
1. Connect an RF cable from the output of one unit to the input of the
test unit.
2. Select corresponding RF channels.
3. Playback a recording of P.B.S. channel including clock set data
and confirm this feature.
4.1.14. 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 resultingin 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.
4.1.15. SPECIAL NOTE
All integrated circuits and many other semiconductor devices are electrostatically sensitive and
therefore require the special handling techniques described under the
"ELECTROSTATICALLY SENSITIVE (ES) DEVICES" section of this service manual.
4.1.16. REPLACEMENT PROCEDURE FOR LEADLESS (CHIP) COMPONENTS
The following procedures are recommended for the 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 must be preheated before installation. -
16
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