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

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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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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. ,,(..

2

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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.

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Phase Lock Loop IC (PLL-IC) which

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Sensitivity, for 3(i)#dissYN

Capture Ratio
Signal-to-Noise Ratio
Total Harmonic Distortion

Mono ,.' ,
Stereo

Image Rejection
Selectivity
Separation at

F,:,ICATIONS

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• 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

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(for 20 dB S+N/N)

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.:120 VAC,'60 Hz

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models. as indicated on rear
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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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1. Built-in adjustable ferrite AM antenna - is adequate for most
areas for AM reception. Swing down and move around 'for best
reception.

11. TAPE MONITOR 2 IN - Accepts output from a s
deck or recorder for tape playback. These jacks ar

'front panel TAPE MON ITOR Switch is set to 2.

2. AM ANTenna Screw Terminal - Connect an external AM/
short-wave antenna to this screw for long-distance AM rocep-
tion. In most areas the built-in antenna will provido oxcollont

reception.

3. FM ANTenna 300n Screw Terminals - Connect
usina standard 300-ohm lead-in to these screws.

4. FM Line Cord Antenna - Connect to the 300n FM s
minal illustrated to provide FM reception in most metr
areas. Disconnect the line cord antenna when using an

FM antenna.

5. FM ANTenna 75n Screw Terminals - Connect to antenna
75-ohm coaxial lead-in. Coaxial cable provides extremely 1111111
resistance to static and other noise.

6. PHONO GND - Accepts the green or black ground wire found
on most turntables. Making this "ground" connection redu
or eliminates hum.

7. PHONO - Accepts output from any turntable equipped with
magnetic cartridge. These jacks are active when SE LECTO R is
set to PHONO.

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· TAPE MONITOR 2 OUT - Permits recording with a second
tape recorder. Also use for duplicating (or Dubbing) tapes being
played through the Amplifier from another Recorder/Player

nnectedtoTAPE MONITOR 11N.

· A SPEAKERS Screw Terminals - Powers main speakers which

10

not have phono jack connectors.
NOTE: Use either phono jack or screw terminals for A speakers,
not both.

14. A SPEAKERS Phono Jacks - Connects to speakers with phono
jock connectors.

NOTE: Use either phono jacks or screwterminals for A speakers,
not both.

· B SPEAKERS Screw Terminals - Powers remote speakers.

· SWITCHED Convenience Outlet - Plug in an audio accessory
which you want turned on and off by the front panel POWER
switch. For example, connect a Tuner to this receptacle; thus,
when you turn the Receiver on and off, the Tuner will auto-
matically be turned on and off at the same time. Power drawn
from th is receptacle shou Id not exceed 100 watts.

8. AUX - Accepts output from any high-level source-a second
tape deck or tuner, a ceramic or crystal phono cartridge, etc.
These jacks are active when SE LECTO R is set to AUX.

9. TAPE MONITOR 1 IN - Accepts output from any tape deck or
recorder for tape playback.
These jacks are active when front panel TAPE MONITOR
Switch is set to 1.

10. TAPE MONITOR 1 OUT - Permits tape recording any source
chosen by the SELECTOR switch. The output from these
jacks is unaffected by the front panel controls. Also use for
duplicating (or Dubbing) tapes being played through the Am-
plifier from another Recorder/Player connected to TAPE
MONITOR 2 IN.

· POWER FUSE - Protects the Receiver from voltage surges,
short circuits and other abnormal operating conditions. If the
dial lights do not go on when POWER is on, check the fuse. If

it is blown, replace it with an identical size and value (3.5A).

18. UNSWITCHED Convenience Outlet - Powers any audio ac-
cessory up to 200 watts. The front panel POWER switch does

not affect this receptacle.

19. AC Cord - Supplies the Receiver's power. Plug the cord into
any 120 VAC, 60 Hz outlet (220/240 VAC, 50 Hz power where
the sets are so marked on the rear for European and Australian

models).

""

7

CONNECTIONS

BEFORE MAKING CONNECTION

1. Do not plug in the Receiver's power cord,

2. Be sure POWER is off.

If you are using 4 ohm speakers, connect only one set of speakers, or
use only one set of speakers at a time. That is, don't useA+B if one
set is 4 ohms. Low impedance speaker systems will tend to trip the
automatic circuit protection/amplifier shut-down circuitry when
operating at high volume levels (to prevent damage from amplifier

overdrive) .

NOTE: To reduce hum, use shioldod nudlo

tions except speakers.

011111011

for all connec-

SPEAKERS

The STA-95 has two sets of A (main) speaker outputs - use only one
set. If your speakers have phono plug inputs, use the Receiver's
phono plug outputs and a set of unshielded speaker cables. Otherwise
use the Receiver's screw terminal outputs.

For maximum bass response, be sure to observe proper phasing.

Connect the + Receiver speaker output to the speaker terminal

labeled A, 1 or +; and the - output to the speaker terminal labeled B,
2 or -. Most speaker wire is marked with a ridge along one conductor
or has one color-coded conductor. If you use preassembled phono
plugs, phasing will automatically be correct.

Connect B (remote) speakers following the instructions above. Be
sure the speakers are phased properly.

NOTES: 1. The STA-95's outputs are designed for 4-16 ohm

speakers. However, when more than one set of speakers

is being connected, use only 8-16 ohm systems. This

will prevent the amplifier from being overloaded.

2. When using the screw terminals, be sure no stray
strands of wire touch a second term inal or the chassis-
a harmful short could result.

3. Connect no more than two sets of speakers to the

receiver.

4. Use only as much wire as necessary to connect the
speakers.

TURNTABLE

Connect the turntable leads to the PHONO inputs. If the turntable
has a ground wire (usually green or black), connect it to the PHONO
GND screw. Plug the turntable's power cord into an AC outlet or the

Receiver's UNSWITCHED convenience outlet.

(NOTE: If the turntable has a ceramic or crystal cartridge, connect it

to the AUX jacks.)

TAPE DECK

For recording, connect the Receiver's TAPE MONITOR 1 OUT
jacks to a Recorder's AUX or Line Input. For playback, connect the
deck's PRE AMP Output or Line Out jacks to the Receiver's TAPE

MONITOR 1 IN jacks. You can Connect a.second deck to the TAPE

MONITOR 2 IN/OUT jacks.

For playback only, you can connect a 3rd deck to the AUX jacks
(assuming you are not already using them).

ANTENNAS

Be sure the line cord FM antenna is connected to the FM ANT 300n

terminal. The built-in AM antenna requires no attention.

If you think you need an external antenna, see HINTS FOR BETTER

SOUND.

AUXILIARY

Plug the output from any high level source into the AUX jacks. This
input is ideal for a second tuner, TV audio, ceramic or crystal phono
cartridges, a tape player, shortwave radio, etc ...(.. .

8

TYPICAL STA-95 SYSTEM

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CHOOSING THE REST 0

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SPEAKERS

No stereo system sounds
speakers, so choose th
afford for your main sp

Of course there are a wide variety of speakers intended primarily for
remote use. Some are weather-proofed for outdoor installations and
others offer the convenience of a built-in volume control. Naturally,
if you plan to use your remote speakers for critical listening, you
should consider using the same type of speakers for both your main
and remote installations.

TAPE DECKS

Until very recently, reel-to-reel tape decks were the only possible
choice for those interested in true high-fidelity. Recent technological
advances have made
sou nd qual ity of

Reel-to-reel decks are a must for those who want to edit their own
tapes and they still have marginally the best performance.

The best cassette docks, equ ipped with special tape bias settings and
noise reduction circuitry, will out-perform many reel-to-reel decks.
They have the additional advantage of compactness and convenient
pop-in loading. In addition, cassettes can be used in the car as well as
at home.

In addition, an 8-track cartridge uses a continuous tape loop wh ich
can provide hours of uninterrupted music. Many 8-track playback
decks are less expensive than record changers and let you use car
tapes at home.

a-rrsck

root-to-reel

and cassette recorders approach the

mach ines.

slightly less fidelity than cassettes or reels,

s. An 8-track recorder plays pre-recorded

n save money by recording new auto tapes.

Your nearest Radio Shack has a complete selection of speakers for

every application and budget.

TURNTABLE

For convenience, most people prefer a record changer (often called
an automatic turntable) to a manual turntable. A changer will play
an entire stack of records and returns the tonearm to its rest at the
end of the last record.

For the best sound, your turntable should be equipped with a
magnetic cartridge. Cartridges equipped with conical styli (needles)

are usually inexpensive and have good sound. But a cartridge with an
elliptical stylus follows the record groove more accurately and, so,

produces better sound. Your Radio Shack store has a selection of

changer systems which come with factory-mounted bases and car-
tridges.

HEADPHONES

Any system can benefit from a good pair of stereo headphones. They
provide convenient private listening and many people find the
heightened stereo very exciting.

Your STA-95's front-panel headphone jack will accept any low
impedance stereo headphones. When shopping, wear each pair of
headphones long enough to be sure they will be comfortable.

ANTENNAS

Under most conditions your receiver's built-in antennas should

provide adequate AM and FM reception. If you have difficulty see

HINTS FOR BETTER SOUND.

..(.

10

BEFORE PLUGGING IN THE

STA-95'

SELECTOR

1.

Double-check all connections - especially the speaker connec-

tions-to assure that all connections are firm and that there are

no shorts.

2. Set the VOLUME control to minimum.

3. All pushbuttons should be out.

OPERATING THE STA-95

SPEAKERS/HEADPHONES

Select any speaker or combination of speakers with the SPEAKE RS
switch. In the A position, the Receiver's power goes to the main
speakers only and in theBposition to the remote speakers only. A

B puts the same stereo signal through both sets of speakers. In the A
REV position, the left/right sound output from the A/Main speakers

will be reversed. Sometimes this reversing of channels can give

interesting effects from various sound sources.

The PHONES jack permits headphone listening with any or all of the
speakers. For private listening, turn the SPEAKERS switch to OUT.

hoose the input you want by turning the SELECTOR switch.

AM - Use the Tuning knob to select a station. Tune for the

highest reading of the SIGNAL meter. Adjust the front-panel

ntrols for best sound.

M - Use the Tuning knob to select a station. Tune for the

1'110hostreading of the SIGNAL meter and rotate tuning knob
until TUNING meter is at null or center position. If the station is
broadcasting stereo, FM STEREO LED will light up. Adjust the

rent-panel controls for best sound.

I

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tile

signal is noisy, try either or both of these solutions:

l.

Press the HI Filter button. (This will filter out some treble, but

signal will still be stereo.)
s the MONO button. (This will leave the fidelity unimpaired,

but the signal will no longer be stereo.)

M MUTE - Use as FM (above), but a special circuit eliminates

Intorstation hiss. When listening to very weak stations, it may be
necessary to set the SELECTOR to FM.

PHONO - Put on a record and adjust the front-panel controls for

best sound.

AUX - Adjust VOLUME, BASS and TREBLE for best sound.

POWER

Press POWER button in to turn the Receiver on. Pressa second time
to turn the Receiver off.

VOLUME

Adjust VOLUME for a pleasant listening level.

BALANCE

Adjust for best stereo sound. Normally this will be at the center
position of this control. However, depending on your speakers, the
program source and/or your listening position, you may find that
other settings provide better stereo sound. Adjust as you see fit.

11

NOTE: If the TAPE MONITOR switch is in the1or 2 position, the

SELECTOR switch will have no effect on the sound. The

MONITOR LED will light up to remind you that TAPE

MONITOR is being used.

TAPE

Playback - Regardless of the input SELECTOR position, set the
TAPE MONITOR switch to the appropriate position (if your Tape

Deck is connected to TAPE MONITOR

TAPE MONITOR switch to1position; if connections are to "2",

use 2 position). When you have finished listening to the- tape, set

the TAPE MON ITOR switch to SOU RCE position.

1

IN and OUT, set the

REBLE

ting a tape) - Your

flnn/Plllyhuol< olrcults built-in. Connect the

IN and OUT; connect
nd OUT.

Now, if you wont
the TAPE DU
of your now
to 2 position
Deck has 3·h

With these same connections, you can make dubbings in the reverse
way with the "master" tape on 2nd Tape Deck, set the TAPE DUBB-

ING switch to 2 ~1position. Then you can set the TAPE MONITOR
switch to position
Deck connected to

t

1

to hear the new recording (assuming the Tape

"1"

has 3-head Tape Monitoring feature).

" tape and duplicate it - set

position; to check the quality

he

TAPE MaN ITOR switch

ding (assuming the 2nd Tape

ture) .

urn the TREBLE control toward
toward "-" to oe-ornphaslzo thorn. In the center position, the control
has no effect on

'1:1'10

sound.

"+"

to boost high frequencies or

LOUDNESS

Press in the LOUDNESS button-the bass and treble are boosted to
compensate for tho ear's reduced sensitivity at low listening levels.

In the normal (out) position, there is no loudness compensation in

lume level.

FM 25#S

For normal FM IIstol1lng, loave FM 2511S button out. If you want to
record a signal bolng broadcast by an FM station using Dolby NR

system, press this button in. Then, when you play back the tape,
you must use a Dolby Decoder (that is, record with a Dolby-type
tape recorder, but withDolby circuit "off"; then play back with
the Tape Deck's Dolby circuitry "on"). If you press the FM 2511S

button in when Iistoning to a Dolby FM signal, its sound will be

excessively "bright" (too much high-frequency emphasis).

If you have a Dolby NRDocoder, you can connect it to the TAPE
MONITOR
the1position. When an FM station is broadcasting a Dolbyized FM
signal, you will enjoy the following advantages (with a Dolby NR
Decoder) :

1

IN/OUT jacks and set the TAPE MONITOR switch to

Filters

The LO and HI Filters elim inate noise on any program source. The

HI

FILter removes FM hiss and record noise while the LO Filter re-

duces turntable rumble. Both filters are activated when pressed in.

BASS

Turn the BASS control toward
toward

has no effect on the sound.

«:»

to de-emphasize them. In the center position, the control

"+"

to boost the low frequencies or

• Improved signal-to-noise ratio

• Full program dynamic range, even at high frequencies

• Improved reception in weak-signal areas

MONO

Press the MONO button to defeat normal stereo operation. The

resuIt is a composite signal (left + right). When you Iisten to weak
FM stereo stations, pressing the MONO button will reduce the hiss,

but the signal will no longer be stereo.

~

12

...."

HINTS FOR

BETTER SOUND

POSITIONING YOUR SPEAKERS

Where you put your speakers is a highly personal matter, depending

largely on the arrangement of your listening room and the way you

listen to music. Where you put your speakers does make a difference
in how your system will sound, so before settling on a final arrange-
ment, try several alternatives.

Bass response is highly dependent on speaker location. For maximum
bass, place the speakers in the corners of your room. Putting th
speakers directly on the 'floor will make the bass even stronger. If th
bass sounds boomy and exaggerated, move the speakers away from

the corner slightly, pull them out from the wall a little or raise them
6 to 18 inches (15 - 45 cm) off the floor.

Stereo

Stereo speakers should be 6 to 8 feet (1.8 - 2.4 m] apart. Putting

them too close together reduces the stereo effect, while placing them
too far apart reduces bass response and creates a "hole in the

middle". Also, most speakers have a tweeter dispersion angle of

about 60°. Ideally your listening position should be in the overlap, so
you may want to angle the speakers slightly toward you for better
stereo.

I.

SOLDER

4FT,8IN(142cm)

II. ANTENNA LEAD-IN

·1

SOLDER

ANY LENGTH

A set of VH F-TV rabbit ears or ones made specially for FM reception
work well in suburban areas. Some deluxe models feature electronic

"tuning" for better directionality. Connect such antennas to the

300n terminals.

0.315' 0119- 0.394"

(I~

ANTENNAS

Under most conditions your STA-95's built-in antennas should be

adequate for AM and FM reception. If you are not satisfied with the

reception, try one of the arrangements listed below.

For FM, build the low-cost folded dipole (illustrated); or buy one
ready-made from Radio Shack (42-2385). Just splice regular 300-

ohm lead-in wire as shown. Apply a small amount of solder and
heat the twisted ends until solder flows evenly over each strand of
wire. Attach the lead-in to the 300n terminals on the back of the

receiver. The antenna itself can be tacked to the back of a record

cabinet or onto a wall-the higher the better.

13

SHIELD CONDUCTOR

~~.,y, :

75-ohm coaxial lead-in

~

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An outside VH F-TV antenna provides
inexpensive "sp Iitter " perm its you t

Receiver to the same antenna. In 'fring

NOTE: To protect your R

outdoor antenna.

lightning arrestor on any

CARING FOR THE STA-95

The ST A-95's genuine walnut case looks best when it is polished
occasionally with lemon oil. Waxing produces a glossier finish, but
can eventually cause a dull wax buildup.

Clean the metal parts of the front panel and the dial face with a soft,
damp cloth (do not use abrasives or solvents).

Thermal Protection

Your Receiver also has built-in thermal overload protection. That
means that it can not become abnormally hot and damage some
portion of the circuitry. If internal temperatures do rise abnormally,
the Receiver will automatically silence itself. If this happens, check
to be sure you have not placed something over the ventilation
holes-if you have, remove it. If you are using speakers with exces-
sively low impedance, the amplifier circuit may be over-driven and
thus producing excessive heat. This can be caused by using 4-ohm
speakers on main and remote-if you use remote with main speakers,

be sure to use either 8 or 16 ohm speakers.

In any case, if the Roceiver does turn itself off, set POWE R to off,

check ventilation and then check to be sure your speakers are proper-

ly connected and that you are not using a combination of 4-ohm
speakers for both main and remote. The protective circuit is triggered
by temperature, thus it may take a few minutes for the circuitry to
cool down and allow the unit to come back on. If everything is OK,
turn power back on. If 'the Receiver does not come back on, you
may have to wait a few more minutes for everything to cool
adequately-it should never take more than about 20 - 30 minutes
for this cool-down cycle. If Receiver still does not come on, check

the fuse (3.5A) on the rear panel. Replace only with the same size
and rating.

Overload Protection

We've built-in an important protection circuit-which protects the

Receiver from overload. If too much current flows in the output
circuit (from excessively low impedance [combinations less than 4
ohms] , shorted speaker terminals, etc.) a protection circuit activates
immediately and the output drops. In such a case, carefully check
the output connections and the speaker impedance (don't use 4-ohm
speakers if you use more than one pair).

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