LG RCT689H, Service Manual

Page: 104 / 165

4-17
DECK MECHANISM ADJUSTMENT
5. Audio/Control (A/C) Head Adjustment
5-1. Prior Adjustment (performed only when no audio output appears in play of the standard test tape)
Purpose of adjustment : To ensure that audio and control signals can be recorded and
played correctly by constantly maintaining distance between
tape and head, and tape tension between the P3
post and the P4 post.
8.3
Fig. C-5-1
A/C Head Base
Fig. C-5-2
Height Adjustment
Screw(B)
Tilt Adjustment
Screw(C)
Azimuth
Adjustment
Screw(A)
X-Value Adjustment
Hole
Fig. C-5-3
A/C Head
Tape
Tape
0.2~0.25mm
P4
A/C Head Assembly
Fixed Screw
Fixtures and tools used VCR (VCP) status Adjustment position
• Blank Tape • Play the blank tape • Tilt adjusting screw (C)
(Empty Tape) (empty tape). • Height adjusting screw (B)
• Driver (+) Type ø 5 • Azimuth adjusting screw (A)
Adjustment Procedure/Adjustment Diagrams
1) Basically use the A/C head assembly adjusted as in
SPEC.
2) Check if there is crumpling and folding of the tape
around the A/C head. If it is, Turn and adjust the tilt
adjusting screw to ensure that the tape corresponds to
the bottom guide of the P4, and recheck the tape path
after proceeding play for 4-5 seconds.
3) Where the tape bottom is not equal to Fig. C-5-3, Adjust
the height by using the height adjusting screw (B) and
then readjust it by using the tilt adjusting screw (C).
Always check the height of the A/C head since the most
ideal height of the A/C head can be obtained when the bot-
tom part of the tape is away 0.2 ~ 0.25mm from the bottom
part of the A/C head.
CAUTIONS