Sony TA-2000F - Alignment and Adjustment Procedures; Test Equipment Required; Power Supply Voltage Adjustment

SECTION 3
ALIGNMENT AND ADJUSTMENT PROCEDURES
3-1. TEST EQUIPMENT REQUIRED
1. Audio Oscillator
Frequency range ............. 10 Hz to 100kHz
Distortion ...........:::ecceeeee 0.03% or less at 1kHz
2. Distortion Meter
Capable of measuring of 0.015% distortion or
less at 1kHz :
Frequency range ............. 20 Hz to 100kHz
Input impedance .. 1!megohm or more
3. Ac VTVM
Capable of measuring rms voltage of 100mV
or less with a frequency range from 10Hz to
100 kHz.
Input impedance ............. 500k ohms or more
4. Attenuator
Capable of attenuating signals 60dB or more.
Characteristic
impedance ............eeeee 600 ohms unbalanced
5. Oscilloscope
Bandwidth ...............cccee 1 MHz or more
6. Dc Voltmeter
Capable of measuring dc voltage of 1SOV and
50V or less.
600 ohm (%4W)
30hm (4W)
Note: 1.When measuring the sensitivity of
the PHONO-1 LOW LEVEL input,
insert a 46 dB pad (shown in Fig. 3-1.)
between the attenuator and input
terminal. The input sensitivity may
be regarded as the reading on the
attenuator plus the pad loss.
2.0dB = 0.775V (r.m.s.)
7. Resistors
attenuator
Fig. 3-1. 46dB pad
3-2. POWER SUPPLY VOLTAGE ADJUSTMENT
Check the power supply voltages before starting
any measurements and readjust them if necessary.
Preparation
1. Remove the top cover as described in Procedure
2-3 and connect the dc voltmeter to the test
points as shown in Fig. 3-2.
Procedure
1. Set the variable transformer for minimum
output.
2. Turn the POWER switch to ON, and then
increase the line voltage up to the rated value.
3. Adjust semifixed resistor R920 (high-voltage
regulator) and R926 (low-voltage regulator) to
obtain 150V and 37V readings respectively
on the meter.
ae
SOCKET
E
—150V
de
———
WwW)
7
6
6 4
ar
R
a
09
iy
6
SX
mz
=
test
poin
rest
point
nig
ae
nes
BRS
ais
sscrne
carci
TRANSFORMER
(SECONDARY
POWER
TRANSFORMER
|
ExMourt
‘
eee
|
ji
"
es
ELECTROLYTIC
CAPACIT
18
@xMourted
on
croesis}
Fig. 3-2.
B Muting /Power Supply Board
| Meter Amp/Headphone Amp
De ou connections
Flat Amp: 1 /Flat Amp- 2
it
Je
eave ae Calibration |
Oe CH)
MIC Amp/ |
PHONO-2
Equalizer
Amp
meee A926 lB R801{R-CH)
‘es (37 Vdc) @ Level Meter Calibration
Fig. 3-3. Parts location