JVC UX-GD7, Руководство по обслуживанию

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(No.MB422)1-17
SECTION 4
ADJUSTMENT
4.1 Measurement instruments required for adjustment
(1) Low frequency oscillator.
This oscillator should have a capacity to output 0dB to
600
Ω
at an oscillation frequency of 50Hz-20kHz.
(2) Attenuator impedance : 600
Ω
(3) Electronic voltmeter
(4) Frequency counter
(5) Wow flutter meter
(6) Test tape
VT712 : For Tape speed and wow flutter (3kHz)
VT703 : For Head angle (10kHz)
(7) Blank tape
TAPE l : AC-225 TAPE II : AC-514
(8) Torque gauge : For play and back tension forward:
TW2111A, Reverse: TW2121A Fast Forward and Rewind:
TW2231A
(9) Test disc: CTS-1000(12cm),GRG-1211(8cm)
(10) Jitter meter
4.2 Measurement conditions
4.3 Radio input signal
4.4 Frequency Range
4.5 Standard measurement positions of volume and
switch
4.6 Precautions for measurement
(1) Apply 30pF and 33k
Ω
to the IF sweeper output side and
0.082 F and 100k
Ω
in series to the sweeper input side.
(2) The IF sweeper output level should be made as low as pos-
sible within the adjustable range.
(3) Since the IF sweeper is a fixed device, there is no need to
adjust this sweeper.
(4) Since a ceramic oscillator is used, there is no need to per-
form any MPX adjustment.
(5) Since a fixed coil is used, there is no need to adjust the FM
tracking.
(6) The input and output earth systems are separated.
In case of simultaneously measuring the voltage in both of
the input and output systems with an electronic voltmeter
for two channels, therefore, the earth should be connected
particularly.
(7) In the case of BTL connection amplifier, the minus terminal
of speaker is not for earthing. Therefore, be sure not to con-
nect any other earth terminal to this terminal. This system
is of an OTL system.
SECTION 5
TROUBLESHOOTING
This service manual does not describe TROUBLESHOOTING.
Power supply voltage :AC 230V (50Hz)
Measurement output
terminal
:Speaker out
:TP101(Measuring for TUNER/DECK/CD)
:Dummy load 6
Ω
AM modulation frequency :400Hz
Modulation factor
:30%
FM modulation frequency :1kHz
Frequency displacement :22.5kHz
AM 522kHz to 1629kHz
FM 87.5MHz to 108MHz
Power :Standby (Light STANDBY Indicator)
Sound Turbo ll / BASS/ TREBLE OFF
AHB PRO
:OFF
Main VOL. :0 Minimum
Travers mecha set position :Disc 1