Panasonic PV-D4733S-K, Service Manual

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moistened with Ethanol.
When using a Cleaning Cassette, make sure to use "DRY" type only
and be aware that excessive use can shorten head life.
Fig. M1
Note:
1. Do not rub vertically or apply excess pressure to the Video Heads.
Do not turn the Upper Cylinder Unit clockwise while cleaning.
2. After cleaning, use a Dry Head Cleaning Stick (VFK27) to remove any
Ethanol remaining on the cylinder tape path. Otherwise, tape damage
will occur.
6.2.2. ADJUSTMENT PROCEDURES
6.2.2.1. BACK TENSION CONFIRMATION
Purpose:
To fine adjust the Back Tension so that the tape runs smoothly with a
constant tension.
Symptom of Misadjustment:
1) If the tape tension is less than the specified value, the tape cannot
come into proper contact with the Video Heads, resulting in poor
picture playback.
2) If the tape tension is too high, the tape will soon be damaged.
Equipment Required:
Back Tension Meter (Made in U.S.A., Purchase Locally)
VHS Cassette Tape (120-Minute Tape)
Specification:
22.4 gf±2.5 gf
(0.220 N±0.025 N)
1. Play back a T120 cassette tape from the beginning for approx. 10 to 20
seconds to stabilize tape movement.
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