Realistic STA-95 Service manual

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STATE

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OWNER'S MANUA

PLEASE READ BEFORE OPERATING THIS EQUIPMENT

STA-95

•

reo receiver

CATALOG NO.31-2082

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CUSTOM MANUFACTUREO FO~ RAOIO SHACK ~ A olvislON OF TANDY CO~PORATION

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THE BRAND WITH OVER 1,000,000 CUSTOMERS

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rights which

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Number of this unit in
Serial Number on the back pnnol of the unit.

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REALISTIC AUDIO PRODUCTS are the proud result of Radio

Shack engineering, research, development, and over 50 years of
experience in electronics. Laboratories and mejor testing facilities are
maintained in Fort Worth, Los Angeles, Boston, Columbus Ohio,
Burlington Iowa, Toronto and Tokyo. In every sense a national
brand, the Realistic label is worn with equal distinction by our highly
original Communications and Citizens Band (two way radio)
products, and numerous other items, includinq: tape, headphones,
antennas, intercoms and tubes.

In choosing this fine Realistic product you have demonstrated a
rather acute awareness of "getting the most for your money:", With
Realistic this is not an idle boast

The "line" was born in Boston, long famous for Yankee

inqenuitv=

and thrift Its original intent was to bridge a gap between $100

equipment and

$25

equipment where, at the time, there was a real

void in hi-ti merchandise.

Early products were a

a

$19.95

speaker, Soon we found ourselves a unique niche as

$39.95

FM tuner, a

$29.95

preamp/amplifier,

manufacturing retailers.

C1Cacity and ability grew simultaneously. Our Realistic Electrostet-

3Relectrostatic tweeter was called a "best buy" by .the country's

leading product-review magazine. Our 10TRF radio out-performed

practically anything then available. And dealers from all over the

world began requesting a Reaslistic franchise ..

Recent "firsts" include: the first medium-cost DC/AC communica-

tions receiver totally engineered in solid state-the Realistic DX-

150A; the first properly designed microprocessor-controlled UHF/
VHF Scanner-Radio; the Realistic Mach One loudspeaker, making

"theater-type sound" affordable; the first lifetime-guaranteed vac-
uum tube; and the Realistic STA-2000 stereo receiver, which com-
bines massive power, modern styling and a host of new ideas-at a
cost fully $100-$200 below its value under traditional marketing
practices.

But of course/-Realistic marketing practices are NOT traditional.

First: the line is restricted in distribution. Second: we do not have
sales representatives and other normal "trade" costs, nor do we waste
money and tools on frequent model changes to attract new dealers-a
new model is a NEW model, a current model is one that gets a steady
stream of improvements at no cost to you and without a lot of wild

(and expensive) claims of novelty. ,,(..

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INTRODUCTION

Your new STA-95 is a highly versatile AM/FM Stereo Receiver which
delivers enough power to drive almost any speaker system. The
"honest"
drivo both "main" and "remote" speakers. And it has the perform-
ance an(l convenience features that distinguish a truly great receiver.

• A

•

• FM Multiplex circuit
provides rock-stable storeo separation even with temperatur
changes.

• A linear IC is used in the Phono Preamp to obtain wide dynamic
range and low distortion.

• Tape Dubbing switch allows two-way tape dubbing without
troublesome rear panel connection changes.

sp

njoy

46

watts per channel over the entire audio bandwidth will

s the FM de-emphasis circuits to let you

ts

by using a Dolby N R decoder.

use linear IC's which assure minimum

mbined with high gain.

Is a

Phase Lock Loop IC (PLL-IC) which

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Audio butputPolllferat no more than

0.3% FetalHarmonic Distortion
into8ohniMftom

Input SensitiytJ:y1,T

Phono,
Phono Overiload

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Distortiont-:

Signal-to-Noise Ratio', ' .

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F

Sensitivity, for 3(i)#dissYN

Capture Ratio
Signal-to-Noise Ratio
Total Harmonic Distortion

Mono ,.' ,
Stereo

Image Rejection
Selectivity
Separation at

F,:,ICATIONS

FI,ER

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: 45 watts per channel,

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mum RMS power, both

Hz

; channels driven

: 2.5mV

:: 150mV

: 160 mV
: 160 mV
: 30~ 20,000 Hz ± 1 dB
:0.1% (at 30 watts)

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: 65 dB

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: 50

dB
: 50dB
:40dB

• Full Tape Monitor control.

• The wideband tuner provides maximum AM fidelity.

• Front panel jacks let you listen to any source or make tape record-
ings without troublesome rear panel connections.

• Built-in automatic thermal and overload protection.

At Radio Shack we also believe a receiver should look as good as it
sounds. The STA-95 comes with a beautiful genuine walnut veneer
case-and it doesn't cost you a penny extra.

*"Dolby" is a registered trademark of Dolby Laboratories.

AM TUNER

Sensitivity

Irnaqe Rejection
RF Interference Rejection

POWER R'EQUIREI\iIENTS

NOTE:

3

Beforebp'erating your STA~95
read this manualcarefully. It will tell you how to connect
your receiver and' how to get, the' most enjoymentfro,m
your system. ., ~

:Terminal: 2511V
:'Radiated: 250 I1V

1m

(for 20 dB S+N/N)

:35idB

RC!1eaExcellent

.:120 VAC,'60 Hz

:(22.Q/240

VAC, 50 Hz for

.Eu~()pea!1.arid Australian

):

models. as indicated on rear
of unit)'

for

the .~irs.t. time, please

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CONTRo,L FUNCTIONS

POWER

Turns the Receiver on when pushed in-off when pushed a second

time.

PHONES

Accepts any pair of low-impedance stereo headphones. The jack is
always "live".

SPEAKERS

OUT - Turns all speakers off for private headphone listening.
A - Connects main speakers only.
A REV - Reverses the left/right sou nd output from the "A" (or

Main) speakers.
B - Connects remote speakers only.
A+B - Connects main and remote speakers.

Fll TER

The LO and

in, the high filter removes hiss and scratches. The low filter reduces
turntable rumble when it is pressed in.

HI

Filter buttons let you filter out noise. When pressed

BASS

Controls low froquencles. At the center position, it does not affect
the sound. Turn clockwise to boost bass response, counterclockwise
to de-emphasize the low frequencies.

TREBLE

Controls high frequencies. At the center position, it does not affect
the sound. Turn clockwise to boost treble response, counterclock-
wise to de-emphasize the high frequencies.
You'll notice that both tone controls are "stepped" for convenient
reference (you can always return to a previous setting by referring to
the numbered step-positions).

TAPE DUBBING

Is a lever-type switch. Normally you'd leave it in the center or
SOU RCE position. If you want to make two recordings at one time-
th is switch wi II perm it that. Use position 1 ~ 2 to dub from TAP

IN 1 to TAPE OUT 2. Use position 2 ~ 1 to dub from TAPE IN 2 t
TAPE OUT 1.

4

MONITA

VOLUME -

und lovo: 'for both channels-from minimum to maximum,

adjust for desired level of sound. It

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SELECTOR

hooses one of five input positions.

AM - Activates the built-in wideband AM tuner.

M - Activates the built-in FM tuner.

M MUTE - Activates the built-in FM tuner and eliminates inter-

tnrlon

hiss.

PHONO - For any turntable equipped with a magnetic cartridge.

BALANCE -

twoon channels. At the center position (you'll feel a slight
thesound will be equal from both channels.

use to provide best stereo balance of

sOllnd

"cntch"},

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LOUDNESS

When pushed in, the switch introduces a special low and hllll!
frequency emphasis into the amplifier circuitry. LOUDNESS on
hances the sound quality at low volume levels by boosting bass and
treble frequencies which the human ear does not hear as well asth
mid-range frequencies. Use the switch position which provides th
most pleasing sound reproduction.

FM 25pS

Makes your Receiver "Dolby FM-compatible". By adding a Dolby
noise reduction decoder or a Dolby tape deck, you can get the

full benefit from superb Dolby FM broadcasts. (Check your local

FM stations to see if any of them offer Dolby broadcasts.)

When listening to a non-Dolby FM (or if you do not have a Dolby
decoder), leave FM 25 J.lSbutton in out position.

MONO

I\UX -

For any high-output source-a second tuner, a crystal or

mlc phono cartridge, a second tape deck, TV, Ham radio, etc.

UB OUT

toreo phone jack serves as an extra tape output. This makes

y to copy tapes or record any program source without changing

r-panel connections. The output should be connected to the

rdor's Auxiliary or Line inputs.

Tuning Knob

unos AM and FM stations.

TUNING Meters

he left meter is for FM and AM signal strength indication; tune
for maximum deflection. The right meter functions on FM only-
this is an FM "Center Tuning" meter.

FM STEREO Indicator

This bright red LED lightsup when the MONO button is out and you

are tuned to a stereo FM signal.

When pressed in, switches the amplifier and tuner from stereo to
monaural operation. In the out position, the amplifier operates in
stereo and the FM tuner automatically switches to stereo when there

is a stereo signaI.

Function LED's These bright red LED's light up to indicate the

function you are using-AUX, PHONO, AM, FM or FM MUTE.

TAPE MONITOR Indicator - This bright green LED lights up when
TAPE MONITOR switch is in the 1 or 2 position.

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