Adjusting And Checking The Mechanism Section - Denon DRM-800A Service Manual

I
4. How to Remove the Meter Circuit Board
(1) Remove the top cover (27) and front panel (16). (Refer to
Step 1.)
(2) Remove the front esc. assembly (9). (Refer to Step 3,)
(3) Remove the three screws (3
x
10 CBTS-P) (30) that secure
the unit board, the seven hooks and remove the meter
board.
Note: When replacing the (tactile-takuto) switch (X) insert
it so it is not raised after assembly.
o
X
7m/~;na
""Eu",.
5. How to Remove the Audio Circuit Board
(1) Remove the top cover (27) and the front panel. (Refer to
Step 1.)
(2) Remove the two cushions (26) attached to the chassis and
the shield bracket (18).
(3) Remove the front esc. assembly. (Refer to Step 3,)
(4) Remove the shield bracket (18).
(5) Remove the wires from the power supply board that are
connected to the unit.
(6) Remove the two screws (3
x
10 CBTS-P) that press the
4-pin jack and 2-pin jack, the three screws (3
x
10 CBTS-P)
that secure the circuit board and the two hooks that secure
the board to the chassis and the board can pulled out of the
assembly.
Note: Most service operations for the audio board can be
performed by removing the bottom plate from the
rear of the chassis. Refer to the previously described
disassembly procedures if it is necessary to remove
the enrire unit.
Assembly is the reverse of disassembly. Each part
must be mounted in the correct position or the unit
may not be able to be installed. Make sure that each
part is mounted correctly during assembly.
6. How to Remove the Power Supply Board
(1) Remove the top cover and front panel. (Refer to Step 1).
(2) Pull out the power switch lever (13) from the power switch.
(3) Remove the wires from the unit that are attached to the
audio board or power supply board.
(4) Remove the three screws (3
x
10 CBTS-P) (30) that secure
the power supply circuit board and raise the board to
remove it.
ADJUSTING AND CHECKING THE
MECHANISM SECTION
1. Exchanging pinch roller
Before exchanging the pinch roller, clean the tape contact sur-
faces of the pinch roller and of the capstan shaft.
Defects on tape playing are primarily caused by a dirty pinch
roller or capstan shaft.
The right pinch roller arm
®
can be detached by removing
the spring
®
and the slit washer
® .
The left pinch roller
arm
@
can be taken out by removing
@,
the nylon nut
@
and washers
@
and
@.
After exchanging the pinch roller, run a tape without a C-90 butt
and verify that no tape curling occurs at the tape guide
@
and the tape guide part on the record/playback head.
Normal condition
Pinch roller arm L
~~~~
/ . /1
I!
Tape
Tape gUide p' h II R mc ro er arm
Nylon nut Erasure head Recording/Playback head
Special nut
Defective running condition
Curl
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