Akai VS-X9EGN

V. HEAD DRUM REPLACEMENT
5-1. REPLACEMENT PROCEDURE
1) Remove the Drum Earth SP Assy.
2) Remove the two Upper Drum fixing screws.
3) Unsolder the eight wires from the Rotary Trans-
former.
(SP-1: WHITE, SP-2: RED, LP-1: YELLOW, LP-2:
BLACK)
4) Install the Upper Drum (HEAD DRUM).
5) Tighten the two Upper Drum fixing screws.
6) Resorder the eight wires as follows.
SP-1 short white to “Y”’.
(WHITE) long white to ““W”’,
SP-2 short red to ‘““Y”’,
(RED) long red to “BL”.
LP-1 short yellow to “BU”.
(YELLOW) | long yellow to “BR”.
LP-2 short black to “BU”.
(BLACK) long black to “R”’.
Long wire
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ree
Fig. 5-1
7) Install the DRUM EARTH SP ASSY.
UPPER_ DRUM
FIXING SCREW
UPPER DRUM
FIXING SCREW
Fig. 5-2
n= SERVICE MANUAL
12
NOTE: For the proper performance, height precisior is
required for the relative height of video heads,
and the head tips are fragile, the following
points should be noted when replacing the
Upper Drum Block.
(a) Do not loosen the set screw on the collor pre-
load.
(b) Before not loosen the set screw on the collar pre-
load.
(b) Before fixing, clean both surfaces where the
upper drum and the rotary transformer part meet
with alcohol.
(c) When installation of upper drum, if it does not
go on to the shaft easily, clean the hole in the
upper drum with alcohol and put a little oil on
the shaft.
(d) Make sure that the upper drum fixing screw holes
on the rotary transformer part and the upper
drum fixing screw penetration holes match
exactly before inserting the fixing screws.
Tighten the two upper drum fixing screws alter-
nately and gradually. Tighten them at 6 kg-cm
torque.
(e
—
5-2. AFTER REPLACEMENT
After replacement, the following adjustments and con-
firmations are necessary for the proper performance.
1) Tracking preset adjustment. (Servo adjustment
Step 1).
2) PB switching point adjustment. (Servo adjustment
Step 2, 3, 4).
3) REC current adjustment. (Video adjustment Step 6,
7, 8, 9).
DRUM EARTH SP ASSY
ie PENETRATION HOLD
fe "
: B=
( |
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UPPER DRUM
FIXING SCREW
UPPER ORUM BLOCK
{HEAD DRUM BLOCK)
HEAD TIP
FIXING SCREW HOLE
—— LOWER 0RUM BLOCK
COLLAR PRELOAD SET SCREW
(DO NOT LOOSEN)
Fig, 5.3