Realistic STA-95 User manual

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Serulce amuaI
STA.95
AM /FM STEREO RECEIVER
Catalog Number: 31 -2082
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CONTENTS
page
1. SPECIFICATIONS 3&4
2, BLOCK DIAGRAM . ...... .5
3. DISASSEMBLYINSTRUCTIONS ....6
4, DIAL STRINGING DIAGRAM. .....6
5. ALIGNMENT PROCEDURE. ,7 _9
6. ALIGNMENT & CHECK POINTS . . .. . ...10
7. LEVELDTAGRAM. .......11
9. 0062 TUNER BOARD .. 18& 19
10. 5042 PRE-AMP BOARD.... .....20
11. 6052 MAIN-AMP BOARD... .......21
12.7159INPUTBOARD... .:...........22
13. 8034 POWER SUPPLY BOARD ,.,23
14. 9035 TONE CONTROL BOARD . . . , ... .24
15. SEMICONDUCTOR LEAD IDENTIFICATION ,,,,..,25
16. ELECTRICAL PARTS LIST . . 26 _ 33
17, MISCELLANEOUS PARTS LIST . .... 34 &35
18. SCHEMATIC DIAGRAM. . SEPARATE SHEET
19. EXPLODED VIEW. .... SEPARATE SHEET

SPECIFICATIONS
NOMINAL LIMIT UN IT
FM SECTION
1, TUNING COVERAGE
2. DIAL CALIBRATION ACCURACY 90 MHz
98 MHz
106 MHz
3. USABLE SENSITIVITY
(NOtSE & DTSTORTION -30 dB)
4, IMAGE REJECTION (at 106 MHz)
5. lF REJECTION (at 90 MHz)
6. FULL LIMITING (at _3 dB)
7. lF BANDWIDTH (6 dB down)
8. DISTORTION (1 mV INPUT)
9. SIcNAL-TO-NOISE RATIO (1 mV INPUT)
10. DE-EMPHASIS 75 psec. (at 50-10,000 Hz)
11. DISCRIMINATOR BANDWIDTH (Peak-to-Peak)
12. AFC HOLDING RANGE (with 1 mV signal)
13. OUTPUT VOLTAGE MONO
(at 75 kHz dev., 400 Hz mod., 1 mV input) STEREO
MUTING THRESHOLD
OVERLOAD, THD at 98 MHz, 100% mod.
(100 mV RF input)
SPURIOUS RESPONSE at 98 MHz
ANTENNA INPUT 3 pV. 1 12\F,103.35 MHz
CAPTURE RATIO (1 mV INPUT)
ALTE RNATE CHANNE L SE LECTIVITY
(0.1 mV input)
100 Hz
1 kHz
10 kHz
87.5 - lo8l
I
I
2.O
5.0 |
50 I
80
2.o I
03 I
65
t1.5 I
400 I
l.2SO
0.75
o.7
'l
,l
80
,\
50
14.
15.
16.
17.
18.
MPX SECTION
1, STEREO SEPARATION
(10096 mod., 1 mV input)
2, DISTORTION 1 KHZ
(100% mod., 1 mV input)
3. STEREO BEACON SENSITIVITY (pilot 7%)
4. RESIDUAL 19 kHz & 39 kHz (1 mV input)
5. SUPPRESSION OF SCA INTERFERENCE
(1 mV input)
AM SECTION
1. TUNING COVERAGE
2, DIAL CALIBRATION ACCURACY 600 KHZ
1,000 kHz
1,400 kHz
3. USABLE SENSITIVITY
(400 H2,30% mod. 600 kH2,1000 kH2,1400 kHz
noise & distortion-20 dB)
4. IMAGE REJECTION (at 1,400 kHz)
5. lF REJECTION (at 600 kHz)
6. AGC FIGURE OF MERIT
(from 100 mV/m at 1,000 kHz)
Radiated
Direct
7, DISTORTION
(400 H2,30% mod., 5 mV/m input)
38
40
30
0.5
10
50
510 - 1660
250
25
35
30
45
1.5
88 - 108
t250
t2SO
t350
3.0
9.0
45
70
3.0
t 1S0
0.8
60
t2
300
t400
0.7b t 2 dB
0.65 t 2 dB
4-16
1.5
1.2
3-16
40
40
520 - 1620
t1b
t30
t40
70
3.5
40
27
32
20
500
40
30
25
30
2.5
MHz
kHz
kHz
kHz
pV
dBf
dB
dB
pV
kHz
o/
,/o
dB
dB
kHz
kHz
V
V
pV
o/
/o
dB
dB
o/
/o
pV
dB
dB
dB
dB
dB
dB
kHz
kHz
kHz
kHz
pY lm
pV
dB
dB
dB
o/
/o

NOMINAL LIMIT UNIT
8. lF BANDWIDTH (6 dB down)
9. OUTPUT VOLTAGE
(400 H2,30% mod., 5 mV/m input)
10. AUDIO RESPONSE
(5 mV/m input from 50 Hz to 2 kHz, 0 dB
@ 1,000 kHz)
11. SELECTIVITY 200 pVlm
12, SIGNAL-TO-NOISE RATIO
(1,000 kHz, with antenna input 5 mV/m)
13. AM BEAT (input 100 mV/m)
AUDIO SECTION
1, RMS OUTPUT POWER
(distortion < 0.3%,20 Hz - 20 kHz)
PER CHANNEL DRIVE 8 O
4a
BOTH CHANNELS DRIVEN B s2
4a
2. IM DISTORTION
(at 30 W output 7O/7,OOO Hz 4l1l
3. HARMONIC DISTORTION (at 30 W output)
100 Hz
1,000 Hz
10,000 Hz
4, FREOUENCY RESPONSE
(AUX, 8 Sl load, 1 W output) 30 Hz - 20 kHz
5. INPUT SENSITIVITY (for 45 W output)
PHONO
AUX
TAPE MONITOR
PHONO MAG
AUX
TAPE MONITOR
BASS 100 Hz
TREBLE 10 kHz
8. EOUALIZATION RIAA: 30 - 15,000 Hz
L PHONO AMP OVER LOAD CAPABILITY (at 1% HD)
10. HIGH FILTER 10 kHz
11. LOW FILTER TOHz
12. LOUDNESS COMPENSATION (Volume -30 dB)
10 kHz
100 Hz
13. CHANNEL SEPARATION
(AUX input 100 - 10,000 Hz)
14. SIGNAL-TO-NOISE RATIO (input shorted)
6. INPUT IMPEDANCE
7. TONE CONTROL
15. RESIDUAL NOISE
16. LOAD IMPEDANCE
PHONO MAG
AUX
120 Volts, 60 Hz AC*
23 WATTS, No Signal
190 WATTS, Full Signal
* 22Ol24O V AC, 50 Hz for European and Australian Models
250
t1
2.5
160
160
50
70
70
r10
t10
-4
28
40
50
52
48
51
0.1
0.1
0.1
o.2
150
-6
-6
4
I
40
65
80
1.0
146-
200
0.3
0.15
0.15
0.3
t 1.5
3
160 t 30
160 t 30
!10!2
t1Ot2
RIAA t 2
100
-Gt2
-Gt2
4x2
9t2
35
4-16
-6
20
32
10
46
49
45
47
58
70
3
kHz
mV
dB
dB
dB
dB
dB
mV
OHM
dB
o/
/o
W
W
W
W
o/,
o/
/o
o/
/o
o/
/o
dB
mV
mV
mV
ks2
ko
ks2
dB
dB
dB
mV
dB
dB
dB
dB
NOTE: Nominal Specs represent the design specs; all units should be able to approximate these-some
will exceed and some may drop slightly below these specs. Limit Specs represent the absolute
worst condition which still might be considered acceptable; in no case should a unit perform
to less than within any Limit Spec.

BLOGK DIAGRAM
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DISASSEMBLY INSTRUCTIONS
1. Removing chassis from Wooden Cabinet. (Refer to Fig. A)
Remove five screws (#88 & #91) from sides and back.
2. Removing the Front Panel. (Refer to Fig. A)
a) Pull off the SPEAKERS, BASS, TREBLE, DUBBING, MONITOR, VOLUME,
BALANCE, SELECTOR and Tuning knobs.
b) Remove five screws (#90) from top and bottom of Front Panel.
Figure A
a,--
rd-
-@ ffi-\
^.-'- I -
(82) .8 .
-t-v)
@'"
DIAGRAM
fully closed position.
@6
DIAL STRINGING
Note: Tuning capacitor should be in
-o

ALIGNMENT PROCEDURES
Do not attempt alignment unless the following equipment is available.
1. AM Signal Generator
2. Oscilloscope
3. AC Voltmeter
4. FM Signal Generator
5. Stereo Modulator
6. Audio Generator
7. Distortion meter
8. DC Voltmeter
9. Frequency Counter
Note: Bemove line cord antenna from FM external antenna terminal when aligning.
AM IF & RF ALIGNMENT
Note: Remove line cord antenna from FM external antenna terminal when aligning
RECEIVER
L451
TAPE OUT
Output of signal generator should be no higher than necessary to obtain an output reading.
Signal Generator Modulation: 30%.
Set SELECTOR switch SW1 to AM.
STEP SIGNAL GENE BATOR
COUPLING
SIGNAL
GENERATOR
F R EOUENCY
RECEIVER
DIAL
SETTI NG INDICATOR ADJUSTMENT
Refer Fig. 4. REMARKS
1Refer Fig. 1455 kHz
(400 Mz Mod.)
Point of non-
i nterference
(on/about
600 kHz)
AC Voltmeter
to TAPE OUT
jack T401 flFT) Adjust for maxi-
mum reading.
2Same as Step 1600 kHz
(400 Hz Mod.) 600 kHz Same as Step 1L401
L451 (OSC Coil)
(ANT Coil) Same as Step 1
3Same as Step 11400 kHz
(400 Hz Mod.) 1400 kHz Same as Step 1
TC1 05
(OSC Trimmer)
TC1 04
(ANT Trimmer)
Same as Step 1
4Same as Step 11000 kHz
(400 Hz Mod.) 1000 kHz Same as Step 1VR402 Adjust for 250
mV Audio
output.
5Same as Step 1i000 kHz
(400 Hz Mod.) 1000 kHz Receive r's
SIGNAL
Meter VR4O1
Adjust for 70o/o
reading of full
scale with input
of 5 mV/m.
Fig. 1 AM ALIGNMENT CONNECTION
I
I

FM RF AND IF ALIGNMENT
For European model, the lowest frequency of FM tuning range should not be below 87.5 MHz.
125a (1 12.5s,)
Zin = 50o (75s}) Zout = 300O (balanced)
FM Dummy Antenna to 300O antenna terminal
Fig.2 FM DUMMY ANTENNA
B
Signal generator output should be no higher than necessary to obtain an output reading
Set Selector switch to FM.
Signal Generator deviation: 75 kYz NOTE: Be sure to disconnect FM line cord antenna during alignment.
STEP SIGNAL GENERATOR
COUPLING
SIGNAL
GENE RATOR
FREOUENCY
RECE IVER
DIAL
SETTING INDICATOR ADJUSTMENT
Refer Fig. 4R EMAR KS
1
Connect to FM
Antenna Termi-
nal through
FM Dummy
Antenna
(300St) Fis. 2
90 MHz
(400 Hz, Mod.) 90 MHz AC Voltmeter
connected to
TAPE OUT
jack
L1 04
(FM OSC Coil)
Ll 01
(FM ANT Coil)
Ll02
(FM RF Coil)
Adjust for
maximum
reading on
AC Voltmeter
2Same as Step 1106 MHz
(400 Hz, Mod.) 106 MHz Same as Step 1
TC1 03
(FM OSC Trimmer)
TC1 O1
(FM ANT Trimmer)
TC1 02
(FM BF Trimmer)
Adiust for
maximum
readi ng
Repeat steps 1 & 2 until no further improvement is possible
3Same as Step 190 MHz
(400 Hz, Mod.) 90 MHz Same as Step 1T1O1 (FM IFT) Adjust for
maximum
readi ng
4Same as Step 190 MHz
(400 Hz. Mod.) 90 MHz TUNING Meter T201 (Bottom)
(Discriminator) Adjust for
center point on
TUNING meter
5Same as Step 190 MHz
(400 Hz, Mod.) 90 MHz
Distortion
Meter
connected to
TAPE OUT
jack
T201 (Top) Adjust for
minimum
d istortion
6Same as Step 198 MHz
(400 Hz, Mod.) 98 MHz Receive r's
SIGNAL
Meter vR202 Adjust for 70o/o
readi ng of fu I I
scale with input
of 1mV
7Same as Step 198 MHz
(400 Hz Mod.) 98 MHz Oscilloscope
connected to
TAPE OUT
jack VR2O1
Adjust so output
just appears with
an input signal
level of 5 pV.
1 50s2
of Receiver.

MPX ALIGNMENT
FM ANTENNA
TERMINAL
(s00 s})
Fig.3 MPX ALIGNMENT CONNECTTON
TAPE OUT
RECEIVER
I
I
I
FM SIGNAL
GENERATOR
FM DUMMY
ANTENNA
300 sl
Set SELECTOR Switch to FM.
Tune for 98 MHz on band.
Signal Generator output level : 1000pV. Deviation: 75 kHz, at 100% modulation of composite signal.
connect Signal Generator to FM Antenna Terminal through FM Dummy Antenna (300 o).
STEP
19 kHz
(PILOT SIGNAL)
MODULATION
Level
SIGNAL
GENERATOR
Freq. Set to
OUTPUT
INDICATOR
Connected to
ADJUST
Refer Fig. 4ADJUST
FOR NOTE
18% Composite 1 kHz
R channel AC Voltmeter to
TAPE OUT jack
of R channel
Adjust input for
audio output of
about 0.65 V
28Yo Composite
1 kHz L channel
AC Voltmeter to
TAPE OUT jack
of R channel VR3O2 Minimum
AC Voltmeter
reading should
be at least 32
dB below reading
in step 1.
38% Composite
1 kHz R channel
AC Voltmeter to
TAPE OUT jack
of L channel VR3O2 Minimum Same as Step 2.
4PI LOT OFF Carrier only
Frequency
Counter Connect
to TP (#18 pin)
of PCB 0062 and
ground
VR301 19 kHz
lf you did not obtain -30 dB readings in steps 2 and 3 (compared with step 1), readjust VR302 until you obtain -32 dB
reading for both steps 2 and 3.
MAIN AMPLIFIER ALIGNMENT
INDICATOR ADJUSTMENT REMARKS
DC Voltmeter VR601 a, bAdjust for 0.005 V - 0.01 V across
R622 a, b (0.33 ohm) with no signal

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ALIGNMENT & CHECK POINTS
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