Service Position; How To Set The "Service Position; Precautions For Cassete Loding In The "Service Position; Mechanism Service Mode - JVC ShowView DELUXE HR-S9850MS Service Manual

Magnetoscope
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1.4 Service position

This unit has been designed so that the Mechanism and
Main board assemblies can be removed together from the
chassis assembly. Before diagnosing or servicing the cir-
cuit boards, take out the major parts from the chassis as-
sembly.

1.4.1 How to set the "Service position"

(1) Refer to the disassembly procedure and perform the dis-
assembly of the major parts before removing the Drum
assembly.
(2) Lower the cassette holder to prepare for the removal of
the Mechanism assembly screws. (Refer to the "Proce-
dures for lowering the Cassette holder assembly" of 1.3
Disassembly/assembly method.)
(3) Remove the combined Mechanism and Main board as-
semblies.
(4) If any other major parts are used, remove them also.
(5) Connect the wires and connectors of the major parts that
have been removed in steps (1) to (4). (Refer to Fig.1-4-
1a.)
(6) Place the combined Mechanism, Main board and other
board assemblies upside down.
(7) Insert the power cord plug into the power outlet and then
proceed with the diagnostics and servicing of the board
assembly.
Notes:
• Before inserting the power cord plug into the power
outlet, make sure that none of the electrical parts are
able to short-circuit between the workbench and the
board assembly.
• For the disassembly procedure of the major parts and
details of the precautions to be taken, see "1.3 Disas-
sembly/assembly method".
• If there are wire connections from the Main board and
Mechanism assemblies to the other major parts, be
sure to remove them ( including wires connected to the
major parts ) first before performing step (2).
• When carrying out diagnosis and repair of the Main board
assembly in the "Service position", be sure to ground
both the Main board and Mechanism assemblies. If they
are improperly grounded, there may be noise on the play-
back picture or FDP counter display may move even
when the mechanism is kept in an inoperative status.
• In order to diagnose the playback or recording of the cas-
sette tape, set the Mechanism assembly to the required
mode before placing it upside down. If the mechanism
mode is changed (including ejection) while it is in an up-
side down position the tape inside may be damaged.
S-Sub board assembly
Demod board assembly
Navigation board assembly
P/S Converter board
assembly
CN6102
CN3502
CN3501
CN902
CN7191
Jack board assembly
SW/Display board assembly
Fig. 1-4-1a
1-4
3D Digital/2M board assembly
Terminal board assembly
TP111
TP4001
D.FF
VR1401
CTL.P
Main board assembly
D/A LEVEL ADJ
TP2253
TP106
A.FM
PB.FM
Audio erase
CP4001
board assembly
CP5302
CP5303
SECAM board assembly
CP5301
CN3012
To ADV.Jog
CN3011
REC Safety
board assembly
CN7001
TPGND
TP7001
(TEST)
1.4.2 Precautions for cassette loading in the "Service
position"
The REC safety board assembly detects cassette loading
as well as cassette tabs. Therefore, after the assembly has
been removed in the "Service position", it is required to set
the switch manually on the REC safety board assembly
when a cassette is loaded.
1.4.3 Cassette loading and ejection methods in the
"Service position".
(1) Insert a cassette halfway in the Cassette holder assembly.
(2) Set the switch on the REC safety board assembly to on
(by pressing the switch).
(3) As soon as the cassette starts to be loaded, set the switch on
the REC safety board assembly to off (by releasing the switch).
(4) Now the desired operation (recording, playback, fast for-
ward, rewind, etc.) is possible in this status.
(5) The switch on the REC safety board assembly does not
have to be operated when ejecting a tape. But be sure to
turn the set to the normal position before ejecting the tape.
Note:
• In the "Service position", the cassette tabs cannot be
detected and recording becomes possible even with a
cassette with broken tabs such as the alignment tape.
Be very careful not to erase important tapes.

1.5 Mechanism service mode

This model has a unique function to enter the mechanism
into every operation mode without loading of any cassette
tape. This function is called the "Mechanism service mode".

1.5.1 How to set the "Mechanism service mode"

(1) Unplug the power cord plug from the power outlet.
(2) Connect TPGND and TP7001(TEST) on the board as-
sembly with a jump wire. (Refer to Fig. 1-4-1a.)
(3) Insert the power cord plug into the power outlet.
(4) With lock levers (A) (B) on the left and right of the Cas-
sette holder assembly pulled toward the front, slide the
holder in the same direction as the cassette insertion di-
rection. (For the positions of lock levers (A) (B), refer to
the "Procedures for lowering the Cassette holder assem-
bly" of 1.3 Disassembly/assembly method.)
(5) The cassette holder lowers and, when the loading has
completed, the mechanism enters the desired mode.
1.6

Jig RCU mode

This unit uses the following two modes for receiving remote
control codes.
1) User RCU mode : Ordinary mode for use by the user.
2) Jig RCU mode
: Mode for use in production and serv-
icing.
When using the Jig RCU, it is required to set the VCR to the Jig
RCU mode (the mode in which codes from the Jig RCU can be
received). As both of the above two modes are stored in the
EEPROM, it is required to set the VCR back to the User RCU
mode each time that an adjustment is made or to check that the
necessary operations have been completed. These modes can be
set by the operations described below.

1.6.1 Setting the Jig RCU mode

(1) Unplug the power cord plug from the power outlet.
(2) Press and hold the "REC" and "PAUSE" buttons on the
VCR simultaneously, while plugging the power cord plug
into the power outlet.
When the VCR is set to the Jig RCU mode, the symbols
( " : " ) in the time display of the FDP are turned off.

1.6.2 Setting the User RCU mode

(1) Turn off the power.
(2) Press the "REC" and "PAUSE" buttons of the VCR si-
multaneously. Alternatively, transmit the code "80" from
the Jig RCU.

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