Zenith XBV243 series Service Manual page 56

REQUIRED MAINTENANCE
The recording density of a VCR(VCP) is much higher than
that of an audio tape recorder. VCR(VCP) components
must be very precise, at tolerances of 1/1000mm, to
ensure compatiblity with other VCRs. If any of these
components are worn or dirty, the symptoms will be the
same as if the part is defective. To ensure a good picture,
periodic inspection and maintenance, including
replacement of worn out parts and lubrication, is
necessary.
SCHEDULED MAINTENANCE
Schedules for maintenance and inspection are not fixed
because they vary greatly according to the way in which
the customer uses the VCR(VCP) and the environment in
which the VCR(VCP) is used. In general home use, a good
picture will be maintained if inspection and maintenance
is made every 1,000 hours. The table below shows the
relation between time used and inspection period.
Table 1
When
inspection is
About 1
necessary
year
Average
hours used
per day
One hour
Two hours
Three hours
Cleaning Patch
VR168 - 923-03485
MECHANISM - VCR
About 3
About 18
years
months
Coat With Isopropyl Alcohol
Fig. C-9-4
SUPPLIES REQUIRED FOR INSPECTION AND MAINTENCE
(1) Grease: Kanto G-311G (Blue) or equivalent
(2) Isopropyl Alcohol or equivalent
(3) Cleaning Patches
(4) Grease: Kanto G-381(Yellow)
MAINTENANCE PROCEDURE
CLEANING
1) Cleaning the video head. First use a cleaning tape.
If the dirt on the head is too stubborn to remove
by tape, use the cleaning patch. Coat the cleaning
patch with Isopropyl Alcohol. Touch the cleaning
patch to the head tip and gently turn
thehead(rotating cylinder) right and left. (Do not
move the cleaning patch vertically. Make sure that
only the buckskin on the cleaning patch comes
into contact with the head. Otherwise, the head
may be damaged.) Thoroughly dry the head. Then
run the test tape. If lsopropyl Alcohol remains on
the video head, the tape may be damaged when it
comes into contact with the head surface.
2) Clean the tape transport system and drive system,
etc, by wiping with a cleaning patch wetted with
Isporopyl Alcohol.
NOTES: It is the tape transport system which comes into
contact with the running tape. The drive system
consists of those parts which move the tape.
Make sure that during cleaning you do not touch
the tape transport system with the tip of a screw
driver and that no force that would cause deforming
or damage is applied to the system.
Drum
(Rotating Cylinder)
Head Tip
Touch this section of cleaning
patch to the head tip and gently
turn the Drum (Rotating Cylinder)
4-20
D35E COMBO - SERVICING