Untitled

ST-9O3O
,tstereoruner
WhatOtherFM TunerCanFaithfully
Render
a SquareWave?
WaveformFidelity-a TrueMeasureof TunerPerformance
Staggeringas the ST-9030technicalspecificationsmay seem, the
real test of true high quality performancelies in waveformfidelity.
Alt|ough the waveformsof all signals in music programsare usually
extremelycomplex,there are two relativelysimple forms-the
squarewave,and the tone burst signals that will clearlyshow how
well the tuner oerforms.
The comparisonhere betweenTechnicsST-9030(wheredesign
considerationswere all aimed at waveformfidelity)and a conventionaltuner (wherewaveformfidelity has not been of prime
importance)clearlyillustratesthe logicalconclusion resultingfrom a
The Ultimatein FM Performance,FeaturingFully
AutomaticlF BandSelection
for OptimumReception
Condition
Frequency Response 2OHz-lBkHz ( + 0.1dB,
-0.5d8) Altemate channelselectivily90dB
(nanow band)
Sensitivity1.2iiVflsa) and T.H.D0.08%
(stereo,wide band)
SuperbFM Tunerfor Superb
FM Reception
The ST-9030tuner, designedexclusivelyfor
high qualityFM reception,achievesan
incrediblyhigh levelof performancewhich
would have been consideredalmost impossibleonly a few years ago. This welcome
situation has been brought about by a
profusionof very significantelectronicand
technologicaladvances.For example,the
19kHzFM pilot signal is removedin the ST9030by a very imaginativepilot cancel circuit,
insteadof the less efficient low-passfilter. An
extremelylinearfrequencyresponseextendingright up past 18kHzis the exciting
result.Anotherexamole'isrevealedin the lF
critical differencein approachto this meansof testing quality and
oerformance.
The very steep "sag" in the squarewave output signal in the conventionaltuner indicatespoor amplificationphase characteristicsin
while the
the low frequencyregion(thusintroducingdistortion),
suppressedsections at the start of the lkHz sine wave signals
signify a contracteddynamic range in the low frequencyregion.
The ST-9030shows clear superiorityover the conventionaltuner.
Althoughthe time lag is not so criticalif it is consistent,the unstable responsepatterns,the shortenedleadingedge amplitudesand
the ringingduringthe off times will introduceaudibledistortion.
stage,which has been divided into independent"narrow" and "wide" bands,
selectedautomaticallyin the ST-9030accordingto transmissionconditions.Evenin
very congestedregions,the astronomical
alternatechannelselectivityof 90dB completelyeliminateseven the slightesttrace of
interferencefrom adjacentstations,while in
less crowded areasthe wide band elevates
receptionquality to a super grade,with
sensitivityot 1.2sN,and a distortionless
THD
of only 0.08% for both stereo and mono.
Other outstandingfeaturesinclude servo
tuning,automatichi-blend,a PLL MPX lC, and
an FM linearfrequency8{anged variable
tuning capacitorin the frontend.
When it comes to high quality receptionof
FM programs,the ST-9030is the right kind of
FM tuner whereonly the best will do.
Two Completely
Independent
NARROW
andWIDEBandlF
Stageswith Automatic
of Optimum
Selection
Conditions
One of the more exciting advancesfeatured
in the ST-9030is the independent,dual,
narrowAivide
band lF stage. For many years,
tuner designershad been searchingfor ways
of getting around the problem posed by the
effectsof mutuallyantagonistichigh
selectivityand low distortion.lt was very
difficultto improveone without resultingin
Etfect of Automatic Bandwidth Swilching
When distortionexceeds0.3% due to adjacent
station interferenceor other causes(top signaltrace),
bandwidthis automaticallyswitchedto nanow lo
restorelowdistortion reception(bottomtrace).
the deterioration
of the other.Technicshas
solvedthis problemby incorporating
2
completelyindependentcircuitsin the lF
stage-a narrowband for ultrasharp
selectionof wantedsignals,and wide band
for optimumS/N ratioand negligible
distortion.The ST-9030
selectsthe appropriatebandautomatically
in accordanceto
receptionconditions,but manualselectionis
also available.
Wide Band lF
Sincethis bandwill normallybe used in
situationswhereselectivityis not of such
criticalimportance,
distortion,stereo
separation,
and captureratio haveall been
pushedto the very limitsof measuring
capabilities.
Employingcompact6-poleLC
f i l t e ro f o u t s l a n d i n g r o u pd e l a yc h a r a c teristics,plus 6-stagedifferentialamplification,
total harmonicdistortion(stereo
and mono)is reducedto an almost unprecedented
0.08%.Superbstereoseparation
ratingsof 50dB(1kHz)and 40dB (10kHz),
and
a capture ratio as low as O.BdBhavealso
beenachieved.
Selectivily
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Total Harmonic Distortion
Slereo Channel Separation
6
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switchesoverto the wide band.But if the
input signalis too weak,or if adjacentstation
signalsare too close to the desiredsignal,
causingspuriousand/orcrossmodulation
interference,
the tuner will remainswitchedto
the narrowband.
Althoughdetectionof input signallevelis
quite a simpletask,detectionof adjacent
stationinterference
requiresa verycomplex
circuitry.The ST-9030is designedto switch
over to the narrowband if interference
noise
causesthe S/N ratio(duringstereo)to drop
below50dB (0.3%distortion).
P L L M P X l C w i t h P i l o ta n d
S u bcar r ierCancelCir cuits
The recentdevelooment
of an lC for the PLL
type N4PXstereodecodercircuithas resulted
in far reachingimprovements,
such as lower
distortionlevel,higherstereoseparation,
and
capacityto cope with the "shock noise"
occurringin conventional
systems.
But one of the majorfeaturesof this circuitis
the pilot cancelcircuit.Althoughnow appearingin manyother tuners,this imaginative
signalremoverwhich avoidscuttingout any
of the high end portionsof the program,is an
originalTechnicsinvention,f irst introducedin
the TechnicsST-9700severalyears ago.
Besidescontributingto greaterwaveform
fidelity,it is also very instrumentalin reducing
distortionin the very high frequencyregions
of the program.
By comparingthe demodulationspectral
distributionsof 1OkHzmodulatedsignalsin
the ST-9030
and a conventional
tuner,the vast
improvement
achievedby the cancelcircuits
becomesvery clear indeed.The ST-9030shows
much less generationof higherharmonics
and other unwantedcomponentscausedby
beat phenomena.
A l 9 k H z s i g n a ls u p p l i e db y t h e l C ,a n d w h i c h
perfectlywith the pilot
has beensynchronized
signal,undergoeswaveformshapinginto a
p u r el 9 k H z s i g n a la, n d i s a m p l iife d i n t h e
stereomutingcircuit(whichpassesthe
.1gkHz
signalonly duringstereo).This is then
fed back to the input side of the MPX to
cancelout the unwantedpilot signal,thus
avoidingany problemsin subsequentnonl i n e a rc i r c u i t s .
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PLL MPX Decoder Block Diagram
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- -,;.
r
i qnr req en.,
, r . . . . . . r - - . . i . l n l e d e r € n c e" s i g n a i n o d u l a l i o n
100%
30d{
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I I n l e d e r e n c . / d e s r e ds i q n a lc u l o u rr a l i o
*200
0
+zo0 +-400
Frequency deviation (kHz)
Narrow Band lF
By employing4 separate4-resonator
ceramic
f ilters(a total of 16 resonators)
which exhibit
a buffer
very good groupdelaycharacteristics,
amplifier.and 6-stagedifferentialamDlification.the ST"9030
attainsthe exceptionallyhigh alternatechannelselectivity
of 90dB (400kHz)
whiie still maintainingvery
good stereoseparation(40d8at 1kHz,and
30dBat 1OkHz),
and very low distortionlevels
(mono0.15%,stereo0.37.).
Signalsfrom the mixercircuitpass through
both lF circuits,and feed into the detector
circuitwhereselectionof the appropriatelF
band occurs.When the lF Selectoris set to
t h e " A u t o " p o s i t i o nt,h e t u n e rw i l l i n i t i a l l y
switch overto the narrowband.lf the input
signallevelexceeds32.6d8f,or if the
f requencydifference(Af)betweenthe tuned
stationand the closestadjacentstationis
greaterthan 400kHz,the tuner automatically
PrlotCancel
sT-9030
Eflect of Pilot CancelCircuii
O u t p u ts p e c t r u mw h e n f . m o d . l 0 k H z i n p u t i s a p p l i e d .L e t t : S T - 9 0 3 0 - n o t ea l m o s tc o m p l e t ea b s e n c e
Conventional
o f 1 9 k H za n d o t h e r u n w a n t e d c o m p o n e n t s . R i g h l
Conventiona tuner without p lot cancel circurt.
ExtendedFrequency
of 2}Hz-1BkHz
Response
(+ 0.1-0.5d8)
Becausethe stereodecodingpilot signalis
now eliminatedby the electronicpilot cancel
circuit,ratherthan a low-passfilter (which
removessome of the wanted
unavoidably
programas well),frequencyresponsein the
ST-S030is improvedby a very significant
margin.In addition,a cancelcircuitfor
removalof the 38kHzsubcarrierhas also
been included.The resultantflat frequency
responseall the way from 20Hzto 18kHzwith
only +0.1, 0.5d8deviationgivesan exceptionallyhigh degreeof high f idelitythat is
still very rarein tunerstoday.
has also eliminatedthe causeot
The ST-9030
the "jitter" problemcausedby mixing
modulatedinput signalsin the MPX.
and
of stereoseparation.
Deterioration
distortionin the high f requencyregionis thus
suooressedevenf urther.
Servo Tuning Block Diagram
8CangedTun ng Capacitor
Front-End
HighSensitivity
with FM Linear
Equipped
Variable
Frequency8-Ganged
TuningCapacitor
The ST-9030
tuner'sfrontend,one of the
most criticalstagesin any tuner,is equipped
with an advancedlinearfrequencyBganged
variabletuning capacitor.The improvementin
sensitivityand reductionof noise levelsis
also due in part to the adoptionof 3 doubletuned circuits,plus dual gate MOS FETsin
the 2-stageRF amplifier and the balanced
mixercircuit.The use of speciallow-noise
Frequency ResPonse
transistorsin the localoscillator,and a tuned
buffercircuitrnsertedpriorto the mixer,also
contributeto the very high stabilityin this
tuner.The tuned buffercircuitemployedhere
o
i s a c o m b i n a t i oonf t u n i n gc i r c u i ta n d j u n c tion FET,includinga 2gangedvariable
I
j
capacitor.lt is very effectivein maintaining
o
waveformfidelity and preventingany reverse
effect of RF signals.
Theseinnovationshavemadethe ST-9030
extremelyrobust,beingcapableof
strongsignals
handlingevenexceptionally
without overload.Spuriousresponseand
Se rv oT u n i n gC i r c ui tfo r
other basic characteristicshavealso been
improvedby verysignificantdegrees.FurSt a b lea n d A c c u r ateT u n i n g
thermore,"hot" portronsof the circuitryhave
invinciblestabilityin stationtuning
Practically
been elevatedabove the glass epoxy coated
is assuredby this advancedelectronicdevice
circuitboard,eliminatingyet anotherpotential
frequency,
and
the
tuned
which locks onto
of the ST-9030'swaveform
degradation
staystheredespiteany minor fluctuationsin
f idelity.
carrierf requency,localoscillatorf requency,
or lF centerfrequency.This meansgreater
reliabilitydue to the completeabsenceof
drift which could leadto distortionand loss
6
of stereo separation.
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When retuningto anotherstation,servo
tuning rs temporarilyswitchecjoff. The
mutingwidth (thedegreeof detuningbefore
E
contracting
mutingsets in) is also readjusted,
'6
5
from *100kHzwhen servotuning is on, to
+50kHzwhen switchedoff. Furthermore,
the
o
centertuning meteris lockedto within
+1OkHzof the centerpositionwhen servo
t u n i n gi s o n .
DetuningFrequencyv$. T.H.D.(Stereo)
i-! t
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l-
I-.r'+50kHz
0
o e l u n i n g l r e q u e n c yl H z )
-50kH,
Automatic Hi-BlendSwitch lmprovesWeak'
Area S/N
To furtherimprovethe qualityof rather
distantor weak FM stations,the hi-blend
feature in the ST-9030is operated
(althoughswitchoverto manual
automatically
When
operationis also naturallyprovided).
the input stereosignaldrops belowa levelof
34.7d8f,the hi-blendmechanismis activated
to suppressnoiseat the slight
automatically
expenseof some stereo separatlon.
PositiveMuting in Nanow and Wide Band
OperationMade Possibleby NAND Muting
noisehas
Completemutingof inter-station
now been made possibleby the NAND
mutrngswitchingsystemwhich automatically
sets the mutingwidth and levelin accordance
with signalleveland whethernarrow(+sOkHz)
or wide (*120kHz)bandwidthis beingused at
any givenmoment.This has been made
possibleby the independentregulationof
muting leveland mutingwidth by the signal
leveland DC signal.
OtherlmportantFeatures
. Precisionsignalmeterlinearto as high as
81dBf,thus providingaccuracyin measurrng
evenvery strongsignals.
3
;
t
3
b
o
. Special75 ohm F{ype antennaconnector
for coaxial cable.75 ohm cableis strongly
recommendedin the interestof noise-free
receotion.
. AC powersupplyline-filterto eliminate
signalsinduced
ripplesand other interference
via the AC powercord. High performancemonolithicoperation
amplifierlC for audiofrequencyamplification,
constantvoltagesupplies
and independent
for both radioand audiofrequencvamplificationcircuits.
ST.9030Block Diagram
ratio delector
,rf amp
detector
lF selectof
amp
l
;
I
i
mulng
distributed
doubJe-diflereniial
TB SW
composite amp
i
auto hi-blend
I
I
I
lF Stage Block Diagram
Block Diagram ol lF Control Functions
:f
Ralio detector
Mutin9
{wrde)
deiector
amp.
detectol
3rd --5th lF amp.
I
Ii
tor output switching i
I
I
i
Flat groupdelayblocr
NarrowlF circuil
W i d el F c i r c u i t
AutomaticMPX
h i - b l e n dc i r c u i t
Low passf ilte;
Servotuningcircuil
Powersupply
nanow lF/ Wide lF
automaticselector
circuit
Mutingrelay
M P Xc i r c u i l
lr
tl
It
Technical
Specifications
RearPanelFacilities
88-108MHz
75 a (unbalanced)
12.8dBf, 1.2 pV
(75O, tHF'58)
S/N 30 dB, 1.2 ttv
(75 o)
S/N 26 dB, 1.1 ttV
(75 o)
S/N 20 dB, 1.0 PV
(75 o)
50 dB quietingsensitivitY
1 8 . 1d B l , 2 . 2t t V
MONO
( 7 5o , I H F ' 5 8 )
38.1dBf,22 ttv
STEREO
(75O, tHF'58)
Totalharmonicdistortion
wide MONO 0.08%(1 kHz)
STEREO0.08% (1 kHz)
narrow MONO 0.15%(1 kHz)
STEREO0.3% (1 kHz)
80 dB (MONO),
s/N
7 5 d B ( M O N O ,D r N )
Frequencyrange
Antennaterminal
Sensitivity
1 . Terminalfor FM antenna75Qcoaxial cable
2. Output levelcontrol
3. Output terminals(Variable)
4 . Output terminals(Fixed)
4€hannelMPX output & FM multipath
outputs
The "Flat"ComponentSystemis dedicatedto
at an affordableprice.
ultimateperformance
Frequency response
20 Hz-18kHz +0.1,
variable
-0.5 dB
20 Hz-15 k4z *0.2,
fixed
Ultimateperformance.Becausein
-0.8.dB
creatingthe "flat" system Technics
Hz-18 kHz +1.5 dB
20
engineersseparatedthe basic
(DrN)
amplifier/tunerinto five components.
AlternatechannelselectivitY
Researchedand developed each
25 dB
wide
-the-art
to
stateof
component
90 dB
narrow
oerfection.Then recombinedthe
Captureratio
0.8dB
components into a system that
wide
2.0dB
providesa magnitudeof performance
narrow
lmage reiectionat
once thought to be purely theoretical.
135dB
98 MHz
Affordableprice. Becauseeach
lF reiectionat
component is priced far lower than
135dB
98 MHz
what you'd expect,consideringits
Spuriousresponse
extraordinaryquality.And becausethe
rejectionat
five-waybreakuplets you buy just the
135dB
98 MHz
you
need-or can
equipmentthat
AM suppression 58 dB (wide)
afford-right now. With the possibility
Stereoseparation
50 dB (1 kHz),
of adding the rest of the system in the
wide
40 dB (10kHz)
future.
40 dB (1 kHz)'
narrow
The "Flat" ComponentSystem
30 dB (10kHz)
consists of:
Carrier leak
ST-9030:FM Stereo Tuner
-6s dB (19kHz),
variable
DC
Preamplifier
Stereo
SU-9070:
-60 dB (19kHz,DIN)
SH-9010:Stereo UniversalFrequency
-70 dB (19kHz,
f ixed
Eoualizer
38 kHz),
-65 dB (19kHz,DIN)
Meter Unit
SH-9020:PealdAverage
SE-9060:Stereo/MonoDC Power Amplifierchannel balance O dB
1.0 pV (75o)
Limitingpoint
Bandwidth(wide/narrow)
300 kHzl200kHz
lF amplifier
FM demodulator 1.5MHz/1.5MHz
MovableCustomRack,
ModelSH-999K
Elegantcustomrackfor Technics
"Flat" componentsor other45cm
units.Sidepanelsblackgrain
veneer,glasstop and front door.
Recordcompartmentholdsseveral
dozenLP's.Foursturdycastersfor
mobilityand easyaccessto backpanel
connections.
mm
Dimensions540x969x400
(WxHxD)
GENERAL
Outputvoltage
0^'1.5V
variable
0.7 V
fixed
27 W
Powerconsumption
V
11Ol120/220/240
Powersupply
Dimensions
x370
mm
450x92
(wxHxD)
7.4 kg
Weight
@Technics
Electric
Matsushita
S r r e c i f i c a t i o n s s u b i e ct to 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 d i n . l a p a n S D 7 D 0 2 0 E