JVC KV-V8 service manual How to set the Service position, Mechanism service mode

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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 chas- sis assembly. Before diagnosing or servicing the circuit boards, take out the major parts from the chassis assembly.

1.4.1 How to set the "Service position”

(1)

Refer to the disassembly procedure and perform disas-

 

sembly of the major parts before removing the Cassette

 

housing assembly.

(2)

Remove the combined Cassette housing, Mechanism

 

and Main board assemblies.

(3)

Connect the wires and connectors of the major parts that

 

have been removed in step (1). (Refer to Fig. 1-4-1a.)

(4)

Place the combined Mechanism and Main board assem-

 

blies upside down.

(5)

Insert the power cord plug into the power outlet and then

 

proceed with the diagnostics and servicing of the board

 

assembly.

Main board assembly

TP4001

CTL.P

TP111

D.FF

SW board assembly

TP2253

A FM

TP106

PB FM

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 procadure 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 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 assem- blies. If they are improperly grounded, there may be noise on the playback picture or FDP counter display may move even when the mechanism is kept in an in- operative status.

In order 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 upside down position the tape inside may be damaged.

When checking the operation or performing adjust- ments to the VCP main unit, it is necessary to connect the power cable (Car Cable) to the VCP main unit so that DC power is supplied. Also, when using the re- mote control unit, it is required to connect the IR re- ceiver. (by using either the provided or optional acces- sories)

CN3006

CP5001

CP5002

Front board

 

 

assembly

 

 

CN7001

 

 

TP7001

TP7002

 

MECHA TEST

GND

 

Fig. 1-4-1a

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)Remove the Front panel assembly and Cassette hous- ing assembly. (Take care not to pull the flat wire.)

(3)Connect TPGND and TP7001(TEST) on the Front board assembly with a jump wire.

(4)Insert the power cord plug into the power outlet.

(5)Turn on the power. When the loading has completed, the mechanism enters the desired mode.

1-4

Image 6 Contents
KV-V8 Specificatios KV-V8J Adjustment information for installation Disassembly flow chartHow to read the disassembly and assembly Disassembly/assembly methodFig. D1 Fig. D4 Mechanism service mode Service positionHow to set the Service position How to set the Mechanism service modeFDP display model FDP display FDP Content Cause EMG detail information Mechanism sensor information Common table of MN*, HD* and M3 Checking for proper mechanical operations Before starting repair and adjustment PrecautionsJigs and tools required for adjustment Manually removing the cassette tape5a Mechanism assembly top side Tape CleaningLubrication DrivePinch roller arm assembly Replacement of major parts Before starting disassemblingHow to set the Mechanism assembling mode 4 A/C head How to removeLoading motor Lever assembly, sub deck assembly, capstan motorReel disk assembly take up Control bracketSub brake assembly take up, control cam Control plateSlide plate Change lever assembly, rotary encoder Take up head, tension arm leverRemove the take up head and tension arm lever Upper drum assembly Rotor assembly How to removeStator assembly Guide rail19a Rotary encoder, change lever assembly, control cam Loading arm assemblies supply, take upAttach the surrounding parts of the guide rail Mechanism timing chart Compatibility adjustment Notes Repeat steps 1 to 10 by using the alignment tape A2FM waveform linearity 3 A/C head phase X-value Height and tilt of the A/C headPlay back the alignment tape a Standard tracking preset Tension pole positionSwitch settings and standard precautions PrecautionRequired adjustment tools Required test equipmentsSlow tracking preset KV-V8 No.49625