Main Adjustments - JVC PC-X130 B Service Manual

7. Main Adjustments
Mi Test Instruments reqired for adjustment
1, Low frequency oscillator
(oscillation frequency : 50Hz to 20kHz)
( Output : 0 dBs with 60 {2 terminator)
2. Attenuator( Impedance : 600 2 )
3. Test Tapes
VTT712: tape speed,wow & flutter measurement
VTT703L : Head azimuth
VMT7036 : 1k/10kHz reference level check
VTT751 : Cross talk check
VTT752 : playback channel check
4, Electronic voltmeter
5. Resistor : 600 (2 for attenuator matching
6. Distortion meter
7. Torque gauge : Cassette type for CTG — N
8. Wow and Flutter meter
9. Frequency counter
Mi Measuring conditions (Amplifier section)
Supply voltage
: AC 230V(50Hz) ; PC — X130E/EN/G/GI
: AC240V(50Hz) ; PC — X130B
Battery DC : 12V
Back up battery : 4.5V
Reference output : Speaker ; — 10dBs (0.25V) /8 Q
: Headphone ; — 29dBs(28mV)/ 32 Q
@ Standard position of function switches
Function SWITCH coecccccceeccccceseccecceccereecsconees TAPE
Tape select SWitCh scccrrseretsereseseeeceseeecens NORMAL
Active hyper DaSScroectececececcccncrecececcsesescercons OFF
Dubbing speed SWitCh errereceessccccceeccceseves NORMAL
Measuring point eee reeeerecesserevesccssesivers Headphone
@ Standard position of volume control
Equalizer frequency(100 Hz, 1 kHz, 10 kHz) -- CENTER
Main volume adjust *ss+rsrrrrseeseeseeeeerreseeeeeeeeeees 13
Test tape for REC/PB verrsessrreeeeees Normal tape (UR8)
PC — X130 B/E/G/GI/E
Standard test frequency
: 1 kHz (unless otherwise specified)
Reference input level : Test point CN301 ; — 18 dBs
For REC/PB, Check & measuring input use
: CN301; — 18.0 dBs (Component side)
4 © TP (BIAS)
O GND
© RCH
1 © LCH
Output for measuring unless otherwise specified
At headphone J301 with dummy load 32 2
@ Measuring condition (Radio section)
Reference output : Speaker ; 50mW(0.63 V) / 8 92
: Headphone ; 0.17MW(0.07V)/32 22
AM frequency vrrsrssersssseeserees 400Hz modulation 30%
FM frequency vsrerrstrsserereseeeerseees 400Hz modulation
frequency deviation 22.5kKHz
@ Standard position of switches and controllers
@ Careful points for adjustment
1. Connect 30 pF capacitor and 33 k {2 resistor to the
output side of the IF sweeper in series while 0.082 u
F capacitor and 1000k Q resistor to the input side in
series.
2.Set output level of the IF sweeper as minimum
as
adjustable,
(No, 1892) 35