JVC KS-FX922R service manual Conditions, S.Values, Adjust, 1-14

Models: KS-FX922R

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Item

KS-FX922R

Item

Conditions

Adjustment and Confirmation methods

S.Values

 

 

 

 

Adjust

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1. Head

Test tape:

Head height adjustment

 

 

 

 

 

 

 

 

 

 

 

 

azimuth

SCC-1659

Adjust the azimuth directly. When you

 

 

 

 

 

 

 

 

 

 

 

 

adjustment

VT703(10kHz)

adjust the height using a mirror tape,

 

 

 

 

 

 

 

 

 

 

 

 

 

 

remove the cassette housing from the

 

 

 

 

 

 

 

 

 

 

 

 

 

 

mechanism chassis. After installing the

 

 

 

 

 

 

 

 

 

 

 

 

 

 

cassette housing, perform the azimuth

 

 

 

 

 

 

 

 

 

 

A line

 

 

 

 

 

 

 

 

 

 

 

 

 

 

adjustment.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1. Load the SCC-1659 mirror tape. Adjust with

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

height adjustment screw A and azimuth

Head shield

 

 

 

 

 

 

 

adjustment screw B so that line A of the

The head is at low position

 

 

mirror tape runs in the center between Lch

 

 

during.

 

 

 

 

 

 

 

and Rch in the reverse play mode.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2. After switching from REV to FWD then to

 

 

 

 

 

 

 

 

 

 

B line

 

 

REV, check that the head position set in

 

 

 

 

 

 

 

 

 

 

 

 

procedure 1 is not changed. (If the position

 

 

 

 

 

 

 

 

 

 

 

 

 

 

has shifted, adjust again and check.)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

3. Adjust with azimuth adjustment screw B so

Head shield

 

 

 

 

 

 

 

The head is at High position

 

 

that line B of the mirror tape runs in the

during REV.

 

 

 

 

 

 

 

center between Lch and Rch in the forward

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

play mode.

Output

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Head azimuth adjustment

level:

 

 

 

 

 

 

 

 

 

 

1. Load VTT724 (VT724) (1kHz) and play it

Maximum

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PBHead

 

 

 

 

 

 

 

back in the reverse play mode. Set the Rch

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

output level to max.

FWD Adj B

 

 

 

 

 

 

 

2. Load VTT703 (VT703) (10kHz) and play it

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

back in the forward play mode. Adjust the

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Rch and Lch output levels to max, with

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

azimuth adjustment screw B. In this case,

 

 

 

 

 

 

 

 

 

 

 

 

 

 

the phase difference should be within 45 .

REV Adj C

HEIGHT Adj A

 

 

 

3.Engage the reverse mode and adjust the output level to max, with azimuth adjustment screw C.

(The phase difference should be 45Conditions or

more.)

phase

(0 )

(45 )

4.When switching between forward and reverse modes, the difference between channels should be within 3dB. (Between FWD L and R, REV L and R.)

5.When VTT721 (VT721) (315Hz) is played back, the level difference between channels should be within 1.5dB.

2. Tape speed

Test tape: VTT712

1.

Check to see if the reading of the F, counter /

Tape speed: Built-in volume

and wow

(3kHz)

 

wow flutter meter is within 3015 3045(FWD

3015

resistor

flutter

 

 

/ REV), and less than 0.35% (JIS RMS).

3045Hz

confirmation

 

 

 

 

Wow

 

 

 

2.

In case of out of specification, adjust the

flutter: less

 

 

 

motor with a built-in volume resistor.

than 0.35%

 

 

 

 

3. Play back

Test tape: VTT724

1.

Play test tape VTT724, and set the volume Speaker out

frequency

(1kHz)

 

position at 2V.

 

1kHz / 63Hz

response

VTT739

 

Play test tape VTT739 and confirm.

: 0

3db

confiramation

(63Hz / 1kHz / 10kHz) 2.

1kHz / 10kHz

 

 

 

1kHz / 10kHz: -1

3dB,

: -1

3db

 

 

 

1kHz / 63Hz: 0

3dB,

 

 

3.When 10kHz is out of specification, it will be necessary to read adjust the azimuth.

The tuner section is of an adjustment-freedesign. In case the tuner is in trouble, replace the tuner pack.

1-14

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JVC KS-FX922R service manual Conditions, S.Values, Adjust, 1-14

FAQ

What test tapes are recommended for head height adjustment?

Test tapes SCC-1659 and VT70310kHz are recommended for head height adjustment.

How can I check the wow flutter and tape speed?

You can check the wow flutter and tape speed by playing test tape VTT712 and using a built-in volume resistor.

What should I do if the 10kHz frequency response is out of specification?

If the 10kHz frequency response is out of specification, it may be necessary to readjust the azimuth. If the tuner section is in trouble, the tuner pack may need to be replaced.