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Untitled
ST-9O38
runer
FMstereo
o, artzSynthesizer
Tuning:
QuartzSynthesizer
in TuningAccuracy
State-of-the-Art
Like any other audiocomponent,an FM tuner
must primarilybe designedas a reproducer
of music. In the case of the ST-9038Quartz
SynthesizerFM tuner, severaldepartures
from conventionaltuner technologyhave
been incorooratedtoward this end-to
achieveof a high degreeof waveformfidelity,
and thus a highlyaccuratereproductionof
the musical programmaterialbeing
broadcastby the radio station.The most
obvious departureis the use of quartzcontrolledtuning.But in many other areas,
the ST-9038is decidedlyunconventional,too.
For example,in the lF section, careful
arrangementof ceramic filters and a "SAW"
filter has been used to achievehigh
selectivityalongwith uniformphase
characteristics.And the use of 19 and 38 kHz
signal cancellerspromotesextremelylow
In
distortionin the high audiofrequencies.
terms of operationalelegance,the ST-9038is
with its unusualscanning
equallyimpressive,
and muting controls,and a choice of manual
or automatictuning.
Tuning
QuartzSynthesizer
HelpsOptimizeWaveform
Fidelity
The Quartz Synthesizerrepresentsone of the
most accuratetuning methods known to
technology.lts unerring,drift-free accuracy
permits you to receivepreciselythe signal
you want to receive,by remaining"zerocentered" in your selectedbroadcast
frequency.By eliminatingthe possibilityof
distortiondue to mis-tuningor drift,
waveformfidelity is considerablyenhanced.
Input
Output
19 kHz Pilotand38 kHz
CancelCircuits
Subcarrier
The 19 kHz pilot and 3B kHz subcarrier
signals are necessaryfor stereo broadcasting.
However,they must be preventedfrom
mixingwith the audiooutput signal,as this
would degradewaveformfidelity. Most tuners
employ a low-passf ilter, which attenuatesthe
pilot and subcarriersignals.but at the same
time can causephaseshift and distortionin
Outpul Level& StereoChannelSeparation
the higher audio frequencies.The ST-9038
uses a more elegant signal-cancelmethod. By
signalback to the
applyinga phase-inverted
.19
and 38 kHz signalsare
MPX stage,the
attenuatedby -65 dB belowthe audiooutput
level.As one benefit, overallfrequency
responseis extremelyflat and wide:
20-18,000 Hz 1*6.1.-0.5 dB). But more
important,very low distortionis maintainedin
the high audio frequencies.
R e d u c t i oonf " J i t t e r "
Distortion
When the broadcaststation's19 kHz pilot
signalbecomesdistorted(as by multipath),
this can causelM distortioncomponentsto
appearin the audio signal.We call this "jitter
distortion"becauseof the patternit produces
on a spectrumanalyzerundertest conditions.
the 19 kHz signalis appliedto
In the ST-9038,
the MPX lC after passingit througha narrowband BPF and differentialamplifier.This
process"cleansup" the 19 kHz signal,and as
a result,jitter distortionis kept very low. lt is
one of the reasonsfor the ST-9038'sverv
cleansound.
negative
regulated-voltage,
balancedpositivei
powersupply,the AF stageachieves
outstandingwaveformfidelity,alongwith the
broadcast
abilityto handleovermodulated
srgnars.
PurelyElectronic
FrontEnd
Five speciallyselected,narrow-tolerance,
variablecapacitance
diodesare used in the
tront end, takingthe placeof a conventional
5-gangtuning capacitor.RF amplificationis
accomplishedwith a dual-gateMOS FET.
Frequencydrift and interference
are severely
circuitsand a
suooressedwith double-tuned
bufferFET betweenthe mixerand oscillator
staoes.
to select"f ine", in which only the strongest,
cleaneststationswill come through;
"standard",in which slightlyweaker,but still
listenablestationswill come through
(corresponding
to about 1% distortionat 1
kHz);or "step scan" (mutingoff), in which
any station,regardlessof quality,will come
through.This last selectionpermitsyou to
do some "stationhunting"for weak or
distantstations.lf you f ind one, you can of
coursetry to improvethe sound qualityby
movingyour antennaaround,usingthe filters
on your amplifier,etc. And when you want to
m o v eq u i c k l yu p o r d o w n t h e d i a l ,j u s t t u r n
t h e " m a n u a lt u n i n g "k n o b ,a n d t u n i n gc a n b e
accomplishedin the same way as with a
tuner.
conventional
PLL MPX Decoder Block Diagram
MutingThresholds
t
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L@dstatims lt
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SAW ( Su r f a c eAco u sti c
Wa v e )F i l t e r i n t he l F S ta g e
Ac h ie v e s"F l a t Gro u p D e l a y"
The lF sectionemploysf ive stagesof
d i f f e r e n t i a lm p l i f i c a t i owni t h s u p e r bl i m i t i n g
lF f ilteringis accomplished
characteristics.
type ceramicf ilters,plus
with two 4-resonator
a SAW f ilterwith independentand selectable
group delayand amplificationcharacteristics.
The arrangement
of these filtersprovides
while at the same time
sharpselectivity,
or
maintaininguniformphasecharacteristics,
"f lat group delay",within the signal.Both of
theseattributesplay an importantrole in
achievinghigh waveformfidelity.lt shouldbe
noted that these filters achievehigh adiacent
which is very important
channelselectivity,
since the ST-9038is designedto receive
stationsthat are only 200 kHz apart on the
FM band.You'lloften find that you can tune
in distantstationsthat you wouldn'tbe able
tunersthat have
to get on many conventional
highersensitivityratings.
9092
94
96
Freqrscy (MHz)
Narrow'Tolerance
Variable
CapacilanceDiodes
Accurateand Effortless
Tuning
Stationson the FM dial are spaced100 kHz
apart,with nothingin betweenbut interstationnoise.The quartzsynthesizer
system
receivesonly those frequencieson which FM
signalsmay be broadcast,in precise100 kHz
divisionsthroughthe 87.6-107.9MHz FM
band.With the digitalread-outof the tuned
MHz frequency,it becomesvery easy to tune
in preciselythe frequencyyou want.
is equippedwith
the ST-903B
Furthermore,
"last one memory",which meansthat the
stationyou were tuned to when the unit was
turnedoff will come on againwhen the unit is
turnedback on. This is of coursetrue of
no
conventionaltuners,but with the ST-903B,
drift can occur becauseof temperature
differences.Evenif the unit is unpluggedor
a powerfailureoccurs,a self-contained
Ni-Cadbatterywill "hold", the memoryfor
about a week.
A u t o m a t i cH i - B l e n dC l e a n s
Up W eak Ster eoSig nal s
When you are receivinga weak,distant stereo
broadcast,backgroundhiss can be greatly
reducedwith the hi-blendfunction,which
Wheneversignalworks automatically.
strengthdrops belowa f ixed threshold,and
as a resultbackgroundnoisewould become
high,the automatichi-blend
unacceptably
combinesthe highertrequenciesinto
essentiallya monophonicaudiosignal.This
hiss,
cancelsout much of the high-frequency
full stereoseparationin
while still marntaining
lf you wish, the hithe lowerf requencies.
blend functioncan be defeatedwith a frontpanelswitch.
Generator
Pink-Noise
The pink-noisegeneratoris a valuable
tool for makinglevelchecksand adjustments
in your audio system.lt becomesmost useful
when you intend to record FM broadcasts.
The output levelcorrespondsto a 50%
so you
modulationlevelin FM broadcasts,
can use it to adlust input levelson your tape
deck.Theywill be properlyset when the
deck's levelmetersdeflect to the -6 dB
position.
OtherFeatures
Firs t St a g e D i f f ere n ti a l ,
A ll-Sta g eD i r e c t -C o u p l eAdF
A m p w i t h S E P PO u t p u t
The audio-frequencyamplifier used in the
ST-9038once again demonstratesheavy
emphasison waveformfidelity.Low-noise
lC's are used throughout,with a differential
amplifier in the first stageand a SEPPoutput
stage,with all-stagedirectcoupling.With a
Choiceof Manualor
A u t o m a t iTc u n i n ga, n dT w o
M u t i n gT h r e s h o l d s
These two featureswork together.First, on
the front panel,you'll noticethat thereare
"UP" and "DOWN" auto-tuningbuttons.
When you presseitherof these buttons,the
tuner will automatically
scan up or down the
FM bandand stop at the first stationthat
fulfills the signal-quality
requirements
that
you selectwith the mutingfunction.The
muting function(stationselector)permitsyou
. A 16-pinbus line connectionpermits
connectionof the optionalSH-9038Micom
unit for programmingstationchanges,on/off,
"absentee" recordingsof FM broadcasts,etc.
. Die-castcabinet(front,top, sides)for
interference
and
sealingout high.frequency
lation.
cross-modu
. Jacks for connectinQan oscilloscopeor
other multi-pathdetectingdevice.Multi-path
can also be detected by connectingthese
jacks to the "aux" inputson your amplifier.In
the "aux" amplifier setting,you will hear
multi-path,so you can adjustyour antennato
m i n i m i z ei t .
. Rear-panel
output levelcontrolfor matching
tunervolumewith other components
connectedto vour amplifier.
witn
t icomprosrammabre
Unit(Si.'ril3,1T"'.'"
)
SH-9O38
IA
StereoSystemComputerization
is
Now a Reality
1038
raro
I
In an age when manythingsare progressing
toward sophisticatedcomputerizedcontrol.
Technicsoffersthe SH-9038Micom
Programmable
Unit.As an optional
companionunit for the ST-9038tuner, the
combinationwill allow you to programan
entirestereosystem.While not an audio
processoritself, it is designedto let you get
more enjoymentout of your system than you
everimaginedpossible.
32-StepProgrammable
MemoryFunctionIncludes
FM StationSelection
"XYZ", and don't want the unit to switch to
use to stop the clock while the tape deck is
"ABC" at 9:00,just turn the programmode to in the "pause" mode.With the stoo-watch.
"manual",and the programwill be overridden.you havea precise recordof recordingtime,
You have this same option when it comes to and don't haveto guessabout time remaining
switchingon or off the other components
before taoe run-out.
connectedto the unit.
The Microprocessor:
A SuccessfulAdaptationof
ComputerTechniques
Die-CastCabinetProvides
ShieldingEffect
The SH-9038'sdie-castcabinet oreventsit
from causinginterferencein other
components.Conversely,extraneousoutside
signals that might affect the microprocessor's
accuracyare kept out.
The brain behind the variousprogramming
functionsof the SH.9038is our own
microprocessorchip. DesignatedMN1400,
the one-chipmicroprocessor
containsa
Designedto be used with the ST-903geuartz .1024x 8-bit ROM (read-onlymemory),and a
Synthesizer
FM tuner,the Micom can be
64 x 4-bit RAM (random-accessmemory).
programmedto rememberup to eight
Additionally,
two CMOS lC's,functioningas
different FM stations on the ST-9038tuner.
8-bit RAM's,providememorycapacityfor up
You can then set the Micom to tune in any ol to eight pre-selectedstations.
thesestations,in any order.at any time of
the day on selecteddays, for a one-week
period.BesidesFM station selectionand
tuneron/off,you can also programthe unit to The switching operationsare correlatedwith
turn on or off any of three additional
the Micom's digital clock. The easy-to-read
componentsptuggedinto the AC oufletsof
timepieceis built into the front panel.and
givescontinuousindicationof minuteand
the power unit, such as your amplifier,tape
deck,etc. All together,the Micom can be'
hour, with the day of the week indicatedbv
programmed
to rememberup to 32 individual an LED.Adjustmentof the clock can easilv
steps in the following order: day-of-the-week, be madewith separatehour and minute
time,station,AC line,on/off.you programthe buttons.Anotherbutton selectsthe dav of
the week.
unit in the "write" mode,and then get a
displayof the programin the ,,read"mode.
You also havethe option of ,,overriding"your
program(manual),or allowing it priority(auto).
This featurecomes in handywhen you,re
For example,if you have programmed'the
Dimensrons
unit to turn station"ABC" on at 9:00,,,ABC" recording.When in the stop-watchmode, the (W x H x D)
gives
clock
readout
a
in
minutes
and
will come on at 9:00 regardlessof what
seconds,up to a total of 59:59,at which point Weioht
slation you were listeningto beforehand.
it
resets
to 00:00.and the cycle is repeat6d.
However,if you want to listento station
Thereis also a hold function,which vou can
PowerUnit for SH-9038
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Stop-Watch
Function
225x97 x 166mm
(8-27132"x 3-1316" x 6-17132"\
3 ks (6.6lb)
i mm
7132")
).9 lb)
P r o g r a m m i n gH
: ere's How Easylt ls.
Desired Setting
How to Operate
Program Slart
Day of Week?
Set Program Mode P u s h b u t t o n t o r
S e l e c l o ra t W R t T E . d e s i r e d d a y ( s ) o f
week (e.9.Monday = 2)
Time of Oay?
P u s h b u t t o n s( 4 d i g i t s )
lor desired time. in
24-hour method. (e.9.
lor 9:38 p.m.push
2 - 1. 3 . 8 )
FM Stalion?
Push button for one of
8 pre-selected
FM stations.
Tape Recording?
To record on deck 1,
p u s h A C 1 .f o r d e c k 2 ,
push AC2. Push both
to record on both
decks.
On or Olf?
Push"on" button
(Off button turns
equipment off at
programmed ttme.)
, in Japan
FRO}IT.END
ST.9O38
12.aMHz
X-lal
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BCO-7 Segmenl Decoder
Binary 8Co-7 Segment
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Mutng Contol
The Principlesof a QuartzSynthesizer
FM Tuner
When you dial the tuning knob of a
conventionalFM tuner, you are causing
changesin the oscillationfrequencies
of the "local oscillator"circuit.In the
"mixer" stage,this oscillation
frequencyis combinedwith the
frequencyof the FM station in such a
way that an intermediatefrequency(lF)
is produced.ldeally,this intermediate
frequencyshould always be 10.7MHz.
It is then isolatedfrom whatever
unwanted signals may be presentby a
series of lF filters.
tuner normallyuses
The conventional
one, or more commonly a series of
variablecapacitorswhich respond not
only to those FM band frequencieson
which stations are actually broadcasting,but to any and all in-between
frequencies.Therefore,the tuner can
drift away from the exact broadcast
frequency,and as a result,the lF can
move away from the ideal 10.7MHz.
This can happenwith temperature
change,the passageof time, and of
cours€accidentalmistuning.
The ST-9038works on an entirelY
differentprinciple,which we call
"quartz synthesizer."Here,the
oscillationof a quartzcrystal(whichis
one of the most stable referencesin
the entire world of electronics)
becomesthe referencetor both the
local-oscillatorf requencyand the
broadcastfrequency.With the quartz
synthesizer,only the frequencieson
which a broadcastsignal might exist
can be received-at preciselyspaced
200 kHz steps on the 88-108 MHz FM
band.And only the proper localoscillatorfrequencycan be generated,
so that the lF will be exactly10.7MHz
for any broadcastyou tune in. Because
the quartz oscillator is so stable,drift
becomesvirtually non-existent.The
tuner can not come out of alignment
becausethere is nothing to retune or
adjust.The selectedfrequencyis
digitallydisplayedon the front of the
unit.Thereis no dial,no pointer,no
string mechanism.So there can not be
of
readingerrorsor mis-alignment
indicators.
In the ST-9038,the quartz synthesizer
tuning methodis combinedwith two
types of tuning operation,automatic
P i n k n o i s eo s c i l l a t o r
and manual.Automaticscanning(with
UP and DOWN sensor buttons)means
that you can scan the dial, in exact
2O0kHz steps, until you arriveat a
stationthat fulfillsthe signal-quality
conditionsthat you selectwith the
muting function.There'salso manual
tuning,which permitsyou to move
quicklyup and down the dial,as You
do with conventionaltuners. Both in
principleand execution,the Technics
ST-9038can safely be called one of the
most technologicallyadvancedFM
tuners that today's "state-of-the-art"
has achieved.
SAW filter
Q u a r t z l o c k e d P L L s y n t h e s i z e rl C
Quartzoscillator
38 kHz subcarrier
cancel
19 kHz pilot cancel
Die-cast shielded wall
PLLIC
D i e - c a s tc a b i n e l
S y n t h e s i z e rb l o c k
Powersupply block
MPX block
Control block
lF block
Manualtuning knob
Amplifier DesignedFor StandardEIA
Styledand Designedto Matchthe SU-8080Integrated
RackMounting
The ST-9038QuartzSynthesizerFM tuner and SH-9038Micom ProgrammableUnit
have been styled and designedto form a harmonioussystem with the Technics
SU-8080DC integratedamPlifier.
SH-9038 Rear Panel
ST-9038Rear Panel
sT-9038
Frequencyrange
Sensitivity(*40kHzdeviation)
S/N 30 dB
S/N 26 dB
S/N 20 dB
IHF usablesensitivitY
IHF S/N 46 dB stereo
quieting sensitivitY
Total harmonicdistortion
MONO
STEREO
S/N (+40kHzdeviation)
MONO
Frequencyresponse
Alternatechannel selectivitY
Caoture ratio
lmaoe reiectionat 98 MHz
lF rdiectibnat 98 MHz
Spuriousresponserejectionat 98 MHz
AM suppression
Stereo separation
1 kHz
10 kHz
leak
Carrier
'19kHz
Channelbalance
250 Hz - 6300 Hz
Limitingpoint
Bandwidth
lF amplifier
FM demodulator
Antenna terminal
Output voltage & imPedance
Powerconsumption
Power supply
Dimensions
1!\/xHxD)
Weight
B y u s i n gt h e i n c l u d e dm o u n t i n g
flanges, both the ST-9038and SH-9038
can be readilyadaptedto fit standard
EIA equipmentracks.
87.6ry 107.9MHz
12+v Q5a)
1.1yV(75(2)
1.qvrsa)
1.2#VflHF'58)
2qrv g5o)
'
0.1% (1 kHz)
0.15%(1 kHz)
7 2 d B ( 7 5d B , I H R
20 Hz - 18 kHz
+0.1 dB, -0.5 dB
75 dB
1 . 0d B
95 dB
105dB
1 0 5d B
55 dB
45 dB
35 dB
-60 dB (-65 dB, IHD
+0.5 dB
1.OpV
250 kHz
1000kHz
75(2(unbalanced)
F{YPeco'axial
0-1.5V(variable)
12W
V 50/60 Hz
AC 1101120122A240
450 x 53 x 293 mm
(17-23132"x 2-3132"x 11-17132"\
5.9 kg (13.0lb)
sH-9038
Weeklyprogramwith a 1 chiP4'bit
mrcroprocessor
possiblefor an entireweek)
(programming
Functions
content
Prooram
-
Day,Time (hours,minutes),FM channel,AC outlets
(ior amp and tuner use, AC1, AC2) on'off.
recarr,
andieset,f.tillJ,fPi?&,f:f:gT*Jlii
writins,
Program
steps
Prosram
content checking caPabilitY
Rewritingof individualprogramsteps and
c-ncellingcapabilityduringwriting
of 32stees{lm:Tffi,#iH,.",j
Maximum
ControlledAC outlets
(maximum
specifications)
tuner 100W
Xts?
?33W
AC2150W
AC line frequencysynchronoustype
Weekly clock (day and time indication)
Power off indication
Individualsecond time counter capability,
Timer
maximum indication59 minutes 59 seconds
Reset,Start, Hold caPabilitY
ln combinationwith TechnicsST-9038
I FM station pre-setcapability
FM Pre-set
(with memory power cut-off compensator)
Auto operation priority function
Other functions
(with program mode in the "Auto" position)
15W
Power consumption
'
50/60 Hz
AC 110112O2201240V
Power supply
Dimensions
450x53x285mm
(!{xHxD)
fi7 -23132"x 2-3132"x 11-7132"\
4.5 kg (9.9lb)
Weight
Clock function
Technics
Electric
Matsushita
S p e c i f i c a t i o n ss u b i e c t t o c h a n g e w i t h o u t n o t i c e .
P r i n t e di n J a p a n