Sony DNW-A220, Руководство по обслуживанию

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4-10
DNW-A220
DNW-A220P
4-4. Video Head Tip Protrusion Check
When performing the periodic maintenance or inspection,
measure the tip protrusion of the video heads using a head
tip protrusion measurement gauge to check them for the
upper drum assembly replacement.
If the tip protrusion of all heads are satisfying the follow-
ing specification and more, it enables to recording and
playing back on the tape.
Head Specification
PB heads for Betacam/Betacam SP format 20 u m
PB heads for BetacamSX format
REC heads for BetacamSX format
If the tip protursion of any one head is under the specifica-
tion, it is recommended that the upper drum assembly
should be replaced early before occurring the trouble at the
recording or playing back.
As for the upper drum replacement, refer to Section 2-2 in
the maintenance manual part 2, volume-1.
Tools
. Cleaning cloth : 3-184-527-01
. Cleaning fluid : 9-919-537-01
.
Head tip protrusion measurement gauge: J-6530-650-A
. Torque screwdriver (3 kg.cm) : J-6325-400-A
. Torque screwdriver’s bit (for M2) : J-6325-380-A
4-4-1. Head Tip Protrusion Measurement
Preparations for VTR
1. Remove the upper frame. (Refer to Section 1-6-3.)
2. Remove the cassette compatment.
(Refer to Section 1-7.)
3. Remove the drum cover.
(Refer to Section 2-2 in the maintenance manual part
2, volume-1)
4. Clean the outer circumference and video heads of the
upper drum (shaded portions in Figure 1).
(Refer to Section 4-2-3 for the cleaning method.)
Figure 1. Cleaning of Drum
Preparations for Head Tip Protrusion
Measurement Gauge
This gauge is the precision equipment. Handle with care.
1. Loosen the adjustment screw fully by turning it
counterclockwise. (Refer to Figure 3.)
2. Clean the probe, positioning flange, and portion
contacting the drum of two legs. (Refer to Figure 3.)
n
Do not apply an excessive force to the probe during
cleaning. If a deposit of u m order exists, measurement
cannot be performed accurately.
4-4. Video Head Tip Protrusion Check
Cleaning cloth
Video heads