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OWNER'S MANUAL
AM/FM
Stereo Receiver
Lahy*tt
Model LR-gOgO
lStock. No. 99-0367bW1
AM/rN
STEREO RECET\'ER
DC DOLBY SYSTEM
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CONTENTS
GENERALDESCRIPTION.... ....,4
INSTALLATION.. ...,....5
ACPower ......5
ConvenienceOutlets ....b
GroundConnection .....5
ANTENNAS ...... .. 5
AM.. ...5
FM .'..b
CONNECTING YOUR ASSOCIATED EOUIPMENT .. ,......7
Loudspeakers .....: ...g
StereoHeadphones. .....10
ConnectingStereoRecordPlayers .......10
StereoTape RecorderConnections .......10
Connecting an 8-Track Tape player . . . lz
DESCRIPTION oF RECETVER CONTROLS.
........12
OPERATING PROCEDURES ...
".." "17
Tuning ln FMStereo
.....17
lnterference On FM
. ra
Reducing Noise On FM Stereo
. . . . 1g
Adjusting Phono lnput Sensitivity On The Receiver
. . . ,n
StereoTapeRecorderOperation . . . .rr
Recording/Playback using one tape recorder
. . . . .21
Simultaneous Recording [tworecordersconnected] .....21
Duplicating [tworecordersconnected] .......21
Playback ltwo recorders connected]
. - . r,
8-TrackTapePlayerOperation ....22
MicrophoneOperation .....22
BassandTurnoverswitchAction .....- .r2
PowerOverload ProtectionCircuit
.......24
TROUBLE-SHOOTING GUIDE
........24
RETURNING THE UNIT FOR SERVICE . .
....25
Shippinglnstructions .....2s
TECHNICALSPECIFICATIONS. .....26
INSERTS: tll schematic Diagram/rnterior parts Location/pc Board Diagrams
121 Operating Chart
t31 Front Panel Operating Controls/Connections to Associated Equipment.
GENERAL DESCRIPTION
The Lafayette 9090 is a highly sophisticated solid-state stereophonic high fidelity receiver that
combines an AM tuner, a highly sensitive FM stereo tuner, and a high quality integrated stereo
amplifier in one single, handsomely styled unit.
The receiver not only offers all the advantages expected from solid-state circuitry such as instant
operation, low current consumption, and cool operation, but also provides extremely low distortion
and noise, plus wide frequency response at its full rated power to ensure the finest sound repro-
duction.
Stereo inputs have been provided for reproduction from a wide variety of external program sources
that you may wish to use -record players, tape recorders, tape players, etc.
Some of the special features that have been incorporated in this receiver to ensure a high degree of
performance and to provide complete flexibility of operation are as follows:
* 75 ohm and 300 ohm antenna inputs for FM.
r. Sensitive dual-gate MOS FET in the FM RF section with 4-section variable capacitor.
x Three 2-element ceramic filters used in the IF section for high selectivity.
ac PLL [PhaseLock Loop] IC used in the FM stereo decoder section for optimum stereo per-
formance with minimum distortion.
x A newly-developed IC functioning as an IF amplifier, a low-distortion Quadrature FM detector,
a driver for the tuning meters, and as a sophisticated FM muting circuit which not only elimi
nates noise between stations on FM in the conventional manner, but also silences the receiver
when not properly tuned to a station.
x Dual Meters used - a conventional signal strength meter plus an FM center-tuning meter for
precise tuning.
x Built-in Dolby Noise reduction circuit for decoding Dolby FM broadcasts.
x Two sets of magnetic phono inputs accommodating a range of cartridge output levels from
2.5 mV to 360 mV [for rated power output].
x Stereo microphone input controlled only by a mic level control for convenient mixing with
other program sources.
x Two-position turnover frequency switches for Bass and Treble controls.
x Direct-coupled OCL power amplifier stages.
x Amplifier output stages protected by a dual system of relay and electronic overload protection
circuitry.
r, Quick-connect output terminals for up to three sets of stereo speakers.
x 2-position 12 dB/octave Low Frequency Filter switch [15 or 4OHz].
x 2-position 12 dBloctave High Frequency Filter switch 17 or 12 KHzl .
r. Dual Tape Monitoring facilities plus special dubbing switch to permit recording from one tape
recorder onto another in either direction.
In order that you may benefit from the many operating and performance features designed into this
receiver, we recommend that you carefully read all the instructions contained in this manual. Also,
we suggest that you keep the manual close at hand and in a safe place so that you can refer to it
when necessary.
4
INSTALLATION
The unit may be used in any convenient location such as an equipment cabinet shelf, table or
bookcase. The amount of heat generated by this unit is small compared to vacuum-tube equipment.
Even so, provision must be made for some ventilation in order to disperse the small amount of heat
that is generated. Do not place books or other objects on top of the unit so that the ventilation
slots are obstructed. Do not place near radiators or other sources of heat.
AC POWER
The receiver is designed to operate from a power source of 105 - I20 votts, 50/60 Hz AC. Do not
attempt to use the receiver on any other power source or damage will result.
CONVENIENCE OUTLETS
Three convenience outlets are provided at the rear of the receiver. The unswitched outlets should
be used to supply AC power to equipment such as a record player and tape recorder. The switched
outlet is controlled by the power on-off switch on the receiver and should be used for equipment
you wish to operate simultaneously with the receiver [a transistorized indoor FM antenna or
booster, for exhmple. Note that neither of the unswitched outlets are protected by the AC fuse in
the receiver.
GROUND CONNECTION
A ground screw at the teceivet's rear [marked GND] provides for optional connection between the
receiver and other Hi Fi components that may be used in a system [such as a record player]. In
many cases, this connection aids in the reduction of hum.
ANTENNAS
AM ANTENNA
The ferrite loopstick built into the rear of the receiver assures adequate reception of all local AM
stations.. However, in the fringe areas, high noise areas, or where surrounding metal objects interfere
with normal reception, a 20 - 30 foot length of insulated antenna wire can be connected to the
terminal designated AM [See Figure 1-A].
NOTE: The ferrite loopstick is mounted on a swivel bracket. For maximum signal pickup, the
loopstick should be swung out-away from the chassis-and adjusted for best reception.
FM ANTENNAS
The antenna is the single, most important factor in obtaining good, distortion-free FM reception.
The finest, most sensitive receiver will not operate properly if it is fed with a poor FM signal. You
should therefore give careful consideration to the selection of an antenna for your receiver if you
-particularly for FM stereo reception.
want the best results
In areas reasonably close to the transmitter, you may be able to use an indoor antenna system such
as a simple folded dipole constructed of 300 ohm twin lead, or a "rabbit ears" antenna similar to
the type sometimes used for TV reception. For the very best FM stereo reception, the use of an
outdoor antenna is highly recommended. These are available in various types [See the Lafayette
catalog]. For reception of stations scattered in many directions, a non-directional type of antenna
may have to be used. If the desired stations lie mostly in one direction, a highly directional type
will provide better results. When using a directional antenna, always orient it for best reception of
the desired station. The correct position will be indicated by a maximum reading of the "SIGNAL"
tuning meter on the receiver.
AM ANTENNA
ANTENNA
t- FM
DIRECTION OF STATION 73n [email protected] GND AM
OUTDOOR
FM ANTENNA
TO FM ANTENNA_ 300 oHM
TWIN LEAD
AM ANTENNA
(20 - 30 FT INSULATED WIRE)
FIGURE 1.A AM EXTERNAL ANTENNA AND 3OO OHM
FM EXTERNAL ANTENNA CONNECTIONS
ANTENNA
r--FM
75!L GND AM
##sffi
INNER
CONDUCTOR
112" - 3/4" INNER
CABLE
CLAMP w, ,------"'- INsuLATIoN
SHIELD
BRAID
75 OHM
CABLE
-COAXIAL
1. Remove approx 1-114" of outer insulation from cable.
2. Remove all but 3/8" of the shield braid.
3. Remove inner insulation, leaving 3/16" of the insulation exposed.
The center conductor should be approx 1/2" long.
FIGURE 1-B 75 OHM FM ANTENNA CABLE CONNECTION
If you presently use an outdoor TV antenna, it can sometimes be used to provide good reception of
FM stations. Simply make a connection between the stereo receiver and TV antenna iead-in, using a
2-set antenna coupler [See Lafayette catalog] . You should remember, however, that some TV an-
tennas are designed to attenriate signals in the FM band to minimize interference on TV from FM
stations [the FM band is located between channels 6 and 7] . In such cases, it will be necessary to
install a separate FM antenna [this may be installed on a lower part of the TV mast] .
FM ANTENNA CONNECTIONS
300 Ohm Connection
When 300 ohm lead-in is used from the antenna, connection to the receiver should be made as
shown in Figure 1-A [to the two terminals marked 300Sl ].
75 Ohm Connection
In areas subject to electrical interference from vehicles, power lines, etc., the use of 75 ohm shielded
cable as a lead-in to the receiver may result in a reduction of the interference. The use of ?b ohm
shielded cable is also required in amplified distribution systems. The 75 ohm lead-in cable to the
receiver is connected as shown in Figure 1-B. Prepare the end of the cable as shown, loosen the
cable clamp [2 screws], then slip the shield braid section under the clamp. Wrap the center [inner]
conductor around the 75O screw terminal and tighten the screw firmly. Now secure the cable
clamp tightly against the shield braid section by means of the two clamp screws.
CAUTION: Make sure that no strands of shield braid come into contact with the Tba terminal
since this will short out the antenna input signal.
Note that 75 ohm cable cannot be connected to the 300 ohm output of a booster amplifier, or a
300 ohm coupler or splitter. Nor can it be connected directly to a 300 ohm antenna, unless a 800
75 ohm matching transformer is used at the antenna. Antennas and booster amplifiers with Tb ohm
-
outputs will present no problems, of course. If you intend to couple the 75 ohm cable to an exist-
ing 75 ohm feeder line, be sure to use a 75 ohm coupler [available from Lafayette] .
CONNECTING YOUR ASSOCIATED EQUIPMENT
WARNING: DO NOT ATTACH OR REMOVE CONNECTING CABLES WITH RECEIVER
SWITCHED ON.
LOUDSPEAKERS
GENERAL
This stereo receiver is equipped with three sets of speaker output terminals, set "A SPEAKERS",
set "B SPEAKERS" and set "C SPEAKERS".
For conventional stereo operation in your main listening area, the left and right speakers [stereo
speaker set "A" as shown in Figure 2] must be connected to the terminals marked "A SPEAKERS".
If you wish to connect a second or third set of speakers in other locations, stereo speaker set "B"
and stereo speaker set "C" must be connected to the applicable set of speaker terminals marked
"B SPEAKERS" and "C SPEAKERS".
Selection of speakers is determined by the position of the "SPEAKER MODE" Switch'
6-10 Fr APARr--+l
.--1sreneospenren /\
LEFr \ ) sEr,,A,, ( / nrcHr
SPEAKER "\ SPEAKER
I-
\i
\/
OPTIMUM STEREO SPEAKER LOCATION
SO THAT SOUND IS FOCUSED ON LISTENER
FIGURE 2 STEREO SPEAKER POSITIONING
(MAIN LISTENING AREAI
SPEAKER CONNECT!ONS
Figure 4 illustrates three sets of stereo speakers connected to the receiver. If you intend to use only
one set of speakers for normal stereo, simply connect the two speakers to the Left and Right
speaker terminals marked "A SPEAKERS".
Figure 3 shows the method used to connect the speaker leads to each set of terminals. To connect a
lead, remove approximately 3/8" of insulation from its end and twist the bare strands of exposed
wire together. Press the lever on the terminal and insert the bared section of the lead into the
opening, as shown. When the lever is released, the lead will be held securely. Be sure to observe
correct polarity; the positive [+] terminal on the speaker must be connected to the [+] receiver
terminal [red lever] and the negative [-] terminal on the speaker connected to the [-] receiver
terminal [black lever] in each case.
The second set of stereo speakers [set "B"] when used as extension speakers in a remote location
must be connected to the Left and Right speaker terminals marked "B SPEAKERS".
A thfud set of stereo speakers [set "C"] may be used in another room. These speakers must be con-
nected to the Left and Right speaker terminals marked "C SPEAKERS".
8
IMPEDANCE OF SPEAKERS USED
When using only one set of stereo speakers, the impedance rating of each speaker used can be any-
where between 4 and 16 ohms. However, when two or three sets of stereo speakers are connected,
no speaker should have an impedance rating of less than 8 ohms [most high fidelity speakers today
are 8 ohms impedance or higher]
Remove insulation
from wire end.
Twist stranded wire.
_ TERMINAL
TERMINAL
TO O SPEAKER
TERMINAL
TO @SPEAKER
TERMINAL
FIGURE 3 CONNECTING SPEAKER LEADS TO
THE RECEIVER OUTPUT TERMINALS
STEREO HEADPHONES
Two sets of stereo phone jacks on the front panel are provided for private stereo headphone listen-
ing, when desired. The outputs of both Phone jacks [A and B] are identical.
If you wish to listen privately without any speakers being on, place the "SPEAKER MODE" switch
to the "PHONES" position.
CONNECTING A STEREO RECORD PLAYER
This receiver is equipped with two sets of phono inputs [PHONO 1 and PHONO 2l f.or use with
record players whose pick-up arm is equipped with a magnetic cartridge [most players are so
equipped]. The two shielded audio cables from a record changer or turntable are normally termi
nated with RCA-type phono plugs. To ensure minimum "hum" and to avoid the possible pick-up
of RF interference [plus possible loss in high frequency tones], the cables from the record player
should be kept as short as possible [they should not exceed 10 feet in length]. Figure 4 shows the
manner in which two record players are connected. If the record player has a ground wire, connect
it to the GND terminal on the receiver. If this results in "hum", disconnect the gtound wire.
If you are using only one record player, connect the left and right output cables from the record
player to the left and right "PHONO 1" inputs. If you wish to use a second record player, connect
its output cables to the "PHONO 2" inputs. Set the "MAG HI-LO" switch to the "HI" position
initially [a procedure for determining the optimum position of this switch is provided in the section
titled "Adjusting Phono Input Sensitivity On The Receiver".
To select either of the phono inputs, set the SELECTOR switch to the PHONO 1 or PHONO 2
position.
STEREO TAPE RECORDER CONNECTIONS
Connecting A Single Tape Recorder
A single stereo tape recorder [cassette, 8-track or open reel] should be connected to the TAPE A
jacks as shown in Figure 4, using shielded audio connecting cables. Note that the input of the
recorder is connected to the TAPE A - REC output jacks on the receiver, and that the output of
the recorder is connected to the TAPE A -- PLAY input jacks on the receiver.
NOTE: If the tape recorder does not have tape monitoring facilities [3rd head] , the output of the
recorder can be connected to the AUX input jacks on the receiver. Playback from the
recorder is then achieved by switching the SELECTOR switch to AUX.
Gonnecting Two Tape Recorders
The first stereo tape recorder [A] must be connected to the TAPE A - REC and PLAY jacks on
the receiver [as shown in Fig. 4].
The second stereo tape recorder [B] is connected in the same manner, but to the TAPE B jacks on
the receiver.
10
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11
CONNECTING AN 8 TRACK STEREO TAPE PI.AYER
Using shielded audio cables terminated with RCA-type phono plugs at each end, connect one end of
each cable to the Outputs on the stereo tape player. Connect the other end of each cable to the
AUX [Left and Right] input jacks on the receiver.
DESCRIPTION OF RECEIVER CONTROLS
We suggest you take the time to read this section carefully. A large number of controls have been
provided on this stereo receiver to ensure complete flexibility of operation. A full understanding of
each control and its functions will enable you to obtain maximum enjoyment for your complete
system.
NOTE: The BASS, MID, TREBLE and VOLUME controls all have a light "detent" action when
rotated throughout their range. This serves two purposes. It will permit you to make a
note of a specific setting for future reference Iall controls have calibration markings], and
will also reduce the possibility of accidental disturbance of the position of a control [even
though the detent has a light actionl. The BALANCE control has only one detent, this
being at the center position [12 o'clock].
SELECTOR SWITCH
This switch selects the progtam source. In detail, each position does the following:
PHONO 1 .... Selects the outputs of a stereo record player connected to the
"PHONO 1" inputs on the receiver.
PHONO2.... Selects the outputs of a stereo record player connected to the
"PHONO 2" inputs on the receiver.
FM.. Selects Automatic FM Stereo reception.
MPX FIL In this position, a special high frequency filter is switched into the
circuit to reduce any high frequency noise that may occur during
FM stereo reception [See section titled "Interference on FM"].
AM.. Selects AM reception.
AUX . Selects a proglam source connected to the "AIJX" input jacks.
MONITOR A_B SWITCH
When this switch is in the SOURCE [center] position, the program selected by the SELECTOR
switch will be reproduced through the receiver and heard in the speakers. When this switch is in the
"A" position, any stereo program source connected to the TAPE A - PLAY inputs will be repro-
duced through the receiver, regardless of the Selector switch selection. When this switch is in the
"B" position, any program source connected to the TAPE B - PLAY input jacks is reproduced
through the receiver and will be heard through the speakers, regardless of the SELECTOR switch
selection [see "Stereo Tape Recorder Operation"].
DUBBING SWITCH
The Dubbing switch is used only when you wish to duplicate a tape [two tape recorders must be
connectedl . For example, if you want to copy the program on a tape on recorder 'oA" onto a
blank tape on recorder "8", you would set the DUBBING switch to the A - B position, place the
12
"A" recorder in the play mode and the "B" recorder in the record mode. To reverse this procedure
[record the tape program on recorder "B" onto a blank tape on recorder "A"] you would set the
DUBBING switch to the B - A position, place the "B" recorder in the play mode and the ,,A,,
recorder in the record mode [see "Stereo Tape Recorder Operation" in a subsequent section].
BALANCE CONTROL
This control, which is positioned behind the VOLUME control, provides left to right balance of the
volume. Initially, this should be set to its normal center [5] position. Turn the control to the left
of the center position to increase the volume of the left channel and turn it to the right to increase
the volume of the right channel.
VOLUME CONTROL
This permits adjustment of the volume for both left and right channels simultaneously.
LOUDNESS SWITCH
The Loudness Switch, when ON, will compensate for an apparent loss of bass and high treble tones
at low volume settings. Such compensation is necessary because a natural peculiarity of the ear
causes it to have a reduced sensitivity to low and high tones when music is played at low volume.
The Loudness circuit will emphasize these tones and thus restore full body and brilliance to the
music. At high volume settings, this action is automatically reduced, and the receiver will assume a
normal tonal response.
MODE SWITCH
This switch determines the manner in which program sources will be reproduced by the receiver.
MONO ' .. . A program source connected to left and right channel input jacks
is mixed and reproduced through both channels and speakers.
Also, a single program source connected to either the left or right
input jack is automatically reproduced through both channels and
is heard from both speakers.
NOTE: During FM operation, switching to ,,Mono,, will disable
the automatic stereo switching circuit of the receiver
and provide only monophonic FM reception.
STEREO . ' This provides stereophonic reproduction of any stereo program
source. This position will also provide automatic FM stereo opera-
tion when the selector switch is in the FM or Mpx FIL position.
TONE SWITCH
This switch, when set to the "FLAT" [depressed] position, will disable all tone controls and the
receiver will produce a normal [flat] tonal response regardless of the existing settings of the BASS,
MID and TREBLE controls. In the VARIABLE position, all tone controls are functional.
BASS CONTROL
This control will allow you to increase or decrease the bass flow tones] in the sound output. When
the indicator line on the control is in the center [0] position, the bass response of the receiver is
normal' Clockwise rotation will increase the bass tones and counter-clockwise rotation will decrease
them. See "Bass Turnover Switch" also.
13
TREBI-E CONTROL
This control operates in the same way as the Bass control, except that it provides adjustment of the
treble thigh] tones. See "Treble Turnover Switch" also.
MOD CONTROL
This control operates in the same general manner as the Bass and Treble controls, except that it
provides adjustment of the midrange frequencies [middle tones]. For normal midrange response'
set the control to the "0" position.
BASS TURNOVER SWITCH
This switch affects the action of the BASS control by changing the frequency below which the
control will affect the tonal response. When the switch is in the 500 Hz position, Bass control
adjustment will affect frequencies from 500 Hz down. When the switchisinthe 250H2 position,
frequencies from 250 Hz down are affected. The 250 Hz position is recommended initially since
this will move the Bass control action into the lower region of the audio spectrum where, generally,
most change is desired. For further information on the action of this switch, see "Bass and Treble
Turnover Switch Action" in a subsequent section of this manual.
TREBLE TURNOVER SWITCH
This switch affects the action of the TREBLE control by changing the frequency above which the
control will affect tonal response. When the switch is in the 2.5 KHz position, Treble control adjust-
ment will affect frequencies from 2.5 KHz up. When the switch is in the 5 KHz, frequencies from
b KHz up are affected. The 5 KHz position is recommended initially since this will move the Treble
control action into the upper region of the audio spectrum where, frequently' most change is
desired. For further information on the action of this switch, see "Bass and Treble Turnover Switch
Action" in a subsequent section of this manual.
LOW FILTER SWITCH
A sharp [12 dB/octave] filtering action can be introduced at either of two frequencies-15 Hz or
40 Hz [the center position is off] . Generallyo the use of the low filters is only required where low
frequency rumble or vibration is encountered while using a record player' If your record player
appears to be generating low frequency "rumble" through motor vibration, switch first to the
Lb KHz position and then, if ineffective, switch to the 40 Hz position. The 40 Hz position will
usually reduce any low frequency noise although it will have some effect on the program material.
The 15 Hz position [which has little or no effect on program material] introduces filtering in the
sub-sonic range and can be particularly useful when a record player is subjected to very low fre-
quency vibrations [from the speakers or some other source]. However, if problems of this nature
are not experienced, leave the switch in the off position-
HIGH FILTER SWITCH
A sharp [12 dB/octave] filtering action can be introduced at either of two frequencies- 7 KHz or
12 KHz [the center position is off] . High frequency filtering should only be used when high fre-
quency noise in the program material is encountered. Such noises might be experienced when
playing worn records which produce "scratching" noises, or with some tapes which might produce
disturbing "hiss". Excessive high frequency noise on FM can also be reduced by means of this filter
switch. When attempting to reduce high frequency noise, always start with l}re 72 KHz position
[this position has least affect on program material]. If this does not reduce the noise sufficiently,
14
you should then go to the 7 KHz position. Since all high frequency filters have some effect on the
high frequency response in the program material, they should not be used unless disturbing high fre-
quency noises are present.
DOLBY FM SWITCH
When depressed, this button will switch in a DOLBY noise reduction circuit, which, when used with
Dolby-encoded FM broadcasts, will provide reception that is remarkably free of noise.
Dolby FM broadcasts employ 25 micro-second pre-emphasis [instead of the conventional
Sin'ce all
75 micro-second pre-emphasis], automatic switching to 25 micro-second de-emphasis also takes
place when the DOLBY FM switch is activated.
The Dolby circuit should not be used with any conventional stereo FM broadcast to provide a
reduction in any noise present. It must be remembered that the Dolby circuit is primarily designed
for use with specially processed broadcasts.
NOTE: If you tune in a Dolby-encoded broadcast with the DOLBY FM button off and then
depress the button, a slight reduction of high frequency response may appear to take
place. This is due to the fact that with the Dolby circuit off, a Dolby-encoded program
has a response with emphasis in the high frequencies; switching the Dolby circuit in will
de-emphasize these high frequencies. Although this may create the illusion of a loss in
the highs, the response is actually being returned to a normal condition.
SPEAKER MODE SWITCH
This switch turns the receiver on and allows you to select one of the five listening modes.
POWER OFF . . . In this position
AC power is disconnected from the receiver and
no sound will be heard. AC power is ON in all other positions.
A .. . .... This connects the sound output to the two speakers attached to
the "A SPEAKERS" output terminals. This position is used when
only two speakers are being used.
B . This connects the sound output only to the set of speakers at-
tached to the "B SPEAKERS" output terminals.
C .. This connects the sound output only to the set of speakers at-
tached to the "C SPEAKERS" output terminals.
A+B . . . This connects the sound output simultaneously to speakers at-
tached to the "A SPEAKERS" and "B SPEAKERS" output
terminals. The "A" set of speakers are normally located in your
, principal listening area; the "B" set of speakers usually in a second-
ary area such as a den.
A+C ... . This connects the sound output simultaneously to speakers at-
tached to the "A SPEAKERS" and o'C SPEAKERS" output
terminals. The "A" set of speakers are normally located in your
principal listening area; the "C" set of speakers usually in another
remote location.
PHONES In this position, all speakers are silenced and the sound output is
connected only to any headphones that are plugged into the
15
"Phones" jacks on the front panel. Note, however, that the sound
output is connected to the headphone jacks in all other positions
of this switch. When listening through speakers, any headphones
plugged into the jacks should therefore be removed to avoid possi-
ble overload of the phones.
"SIGNAL" METER [AM and FM]
This meter is used for all tuning on AM, and for initial tuning on FM lthe FM "TUNING" meter is
used for final, more precise tuning on FM]. Tune for a maximum reading on this meter on AM.
The meter also indicates the relative strength with which various stations are received on AM or FM.
For example, a station producing a reading of 5 is being received with greater strength than a station
producing a reading of 3.
FM "TUNING" METER
This is a special center-reading meter which is used for precise tuning to the center of an FM station
to assure optimum FM reproduction. After the station is tuned in, finely adjust the tuning control
for a center reading. Note that the pointer will swing toward the left or right of center if you are
mistuned. If the meter pointer is over to the right, tune slightly toward the left on the main tuning
dial; if the meter pointer is over to the left, tune slightly toward the right on the main tuning dial.
FM STEREO INDICATOR
When you tune in an FM stereo station, the STEREO Indicator will light up, indicating that FM
reception is stereophonic. When you a.re tuned to a monophonic FM station, the STEREO Indicator
will not light.
Any stereo station which produces an unsteady "flickering" stereo indication must be considered
too weak or noisy for proper stereo reception [although it may be good enough for mono
receptionl.
Note that placing the MODE switch in the MONO position will disable the automatic FM stereo
switching circuit and extinguish the light, even on a stereo broadcast.
AUDIO-MUTE SWITCH
This switch, when set to the ON position, will automatically reduce the volume of the receiver to a
low level regardless of the existing volume control setting. This feature will enable you to lower the
volume temporarily, when you find it necessary to momentarily interrupt your listening [to answer
a phone, etc.].
FM-MUTE SWITCH
One of the normal characteristics of FM is the loud "rushing" noise heard between stations. The
receiver incorporates a special muting circuit which may be used to eliminate this noise between
stations on FM, so that when tuning over the dial each station will "break through" from a back-
ground of silence. In addition to eliminating inter-station noise, the muting circuit also causes the
receiver to be silenced if you are not properly tuned to an FM station. This second function, which
can be described as "detune muting", is designed to guard against improper tuning on FM. For
additional information, see "Operation of the FM Mute Circuit" in a subsequent section of this
((ON" position.
manual. To activate the circuit, set the FM-MUTE switch to the
16
TUNING CONTROL
This control is used to tune in AM or FM stations. Use the 88 to 108 MHz scale on the tuning dial
for FM stations, and the 55 [550 KHz] to 160 [1600 KHz] scale for AM stations.
MIC LEVEL CONTROL
This control adjusts the microphone input level for both the left and right channels simultaneously
providing you are using two microphones [see Stereo Mic Input Jack].
STEREO MIC INPUT JACK
This is a stereo input jack for left and right channel microphones. When using two microphones,
you will need to connect them to a 3-conductor phone plug [the type used by stereo headphones].
A single microphone with a 2-conductor phone plug may also be plugged into this jack, which will
connect it to the left input channel in the receiver [see section titled "Microphone Operation',].
Microphones used should have an impedance between 600 and 10 K ohms
[dynamic type] for best
results.
OPERATING PROCEDURES
Before attempting to operate the system, we urge you to check the following:
1' Make sure that at least one set of stereo speakers have been connected to the output terminals
on the receiver.
2. Make sure the receiver SPEAKER MODE switch is in the "OFF" position, and that you have
properly connected any other associated equipment you intend to use, such as record players
or tape recorders. For FM reception, you must have an external antenna properly connected,
as indicated previously. Then connect the AC power cord to an electrical ouilet supplying
105 - 120 volts, 50/60 Hz AC.
Refer to the charb titled "Quick Guide To Operating Your Receiver" and set all operating con-
trols and switches in the positions indicated for the particular type of operation desired.
When the SPEAKER MODE switch is rotated clockwise beyond the OFF position, the dial
lights will come on, indicating that the unit is ready for operation. Select your program source
[FM, Phono, etc.] and adjust the VOLUME control for desired volume from all speakers.
NOTE: When the receiver is first switched on, there is an approximate 6 second delay before
sound is heard from the speakers. The delay is due to the activation of the built-in over-
load protection circuit which consists of a combination of electronic and relay circuitry.
Howevet, if no sound is heard from one or both speakers after 9 or 10 seconds, switch the
power OFF and see section titled "Power Overload Protection Circuit".
TUNING IN FM STEREO
To select an FM stereo broadcast, proceed as follows:
1. Switch the receiver on and set the Program Selector switch to the ('FM" position.
2. Adjust the VOLUME control for a suitable listening level.
3. Tune across the FM dial observing the FM STEREO indicator light on the receiver. When it
illuminates, you know that you are tuned to a stereo broadcast.
17
INTERFERENCE ON FM
FM stereo broadcasts.ue more susceptible to noise pickup than regular FM monophonic broadcasts.
Provision has therefore been made in the receiver to permit reduction of these noises by means of
special high frequency filters. However, before attempting to use any of these filters, remember the
following:
tal Noise or distortion may be on the record or tape being played by the FM station, or even by
the FM station itself.
tb] Your antenna may not be properly oriented for best reception, or may be inadequate for good
signal pick up from the desired station [see section on FM antennas].
tcl Nearby electrical signs, automobiles, etc., may sometimes cause annoying interference. These
electrical disturbances are usually picked up by the antenna lead-in [if you are using a roof
antenna], and can sometimes be reduced by using 75 ohm shielded cable.
REDUCING NOISE ON FM STEREO
1. If the noise is present when the MODE switch is in STEREO but disappears when set to
MONO, you should try the filter provided in the MPX FIL position of the program selector.
This filter has negligible effect on the high frequency response of the program, but is helpful in
reducing high frequency noise on FM stereo.
2. If the noise is still present, set the HIGH FILTER switch to the 12 KHz position. If this does
not reduce the noise sufficiently, use the 7 KHz position. Although the use of this filter will
affect the higher frequencies on the progmm material lthe 12 KHz position will have the least
effectl, any noise present will be significantly reduced.
18
OPERATION OF THE FM MUTE CIRCUIT
This receiver incorporates a sophisticated FM muting circuit with dual functions. One of its func-
tions is to eliminate the "rushing" noise normally heard between FM stations. This form of FM
muting is of the conventional type found in other receivers.
A second function of this FM muting circuit is that it will mute [silence] the receiver if you are not
properly tuned to an FM station-even though the station may be an extremely strong one. This is
graphically illustrated in Diagram A. Correct practice is to tune the FM station in so that the FM
TUNING meter reads precisely at its mid-point. If the receiver is improperly tuned, causing the
pointer to move outside the shaded area shown in Diagram A, muting will automatically occur and
the receiver will be silenced. This action will take place even with the strongest signal. This unique
form of "detune muting" is designed to guard against improper FM tuning.
NOTE: Rapid tuning across the dial will cause the receiver to remain in a state of almost con-
tinuous muting. When tuning across the dial [in search of an FM station offering music
of your preference, for examplel , tune slowly to avoid this condition.
This dual muting system is activated by setting the FM IVIUTE switch "on", and defeated when the
switch is off.
If receiver is detuned sufficiently to cause pointer to go
outside the shaded area, muting will occur even though
signal meter shows a high reading.
2
SI
DIAGRAM A "DETUNE MUTING'' ACTION
19
ADJUSTING PHONO
INPUT SENSITIVITY ON THE RECEIVER
Provision has been made to accommodate the output from virtually any magnetic cartridge, high or
low, by equipping this receiver with a phono sensitivity switch. This switch is located on the rear
panel of the receiver and is marked "MAG HI-LO".
CAUTION: Never set the phono sensitivity switch to the "HI" (High) position when using car-
tridges with a high output level. This may overload the input stages in the receiver,
possibly resulting in distortion in the sound output.
The "LO" (Low) position provides the least amount of gain and is therefore suitable
with the higher output cartridges. The "HI" position is designed to use with car-
tridges with low outputs.
The following procedure should be used to obtain a proper setting for the phono sensitivity switch.
1. Set up complete installation of the receiver [including speakers, FM antenna, AC power, etc.].
A record player should be connected to the PHONO 1 inputs, as instructed previously, and the
Phono Sensitivity switch set initially lo "LO".
NOTE: The Phono Sensitivity Switch setting will affect both sets of Phono inputs [Phono 1
and 21. If two record players are to be used with the receiver, identical or very simi-
lar cartridges [in terms of output level] should be used for each record player.
2. Set all controls for "FM Stereo" operation [See chart headed "Quick Guide to Operating the
Receiver"].
3. Tune in a strong FM station and set the VOLUME control to produce normal listening volume.
Leave the volume control in this position.
4. Operate the record player, using a stereo record containing the same general type of music
being broadcast on the selected FM station.
5. Alternately, switch between the "Phono 1" and "FM" positions on the Program SELECTOR
switch. Compare the output level from the speakers in each position. If the sound output is
lower in the "Phono" position, set the "MAG HI-LO" switch to the "HI" position and com-
pare once more. Remember, the object of this procedure is to find a phono sensitivity setting
which will produce approximately the same output level as is heard on FM [no distortion
should be present eitherl. Once the proper sensitivity position has been found, it will not be
necessary to change it again unless the phono cartridge is changed.
NOTE: An exact matching of the volume of FM and Phono is not likely. Simply find the
position which provides the closest match.
20
STEREO TAPE RECORDER OPERATION
RECORDING/PLAYBACK USING ONE TAPE RECORDER
To record a stereo program on a tape recorder connected to the TAPE A - REC and TAPE A -
PLAY iacks [as shown in Figure 4], select the desired program source [FM, Phono, etc.]. The
TAPE A - REC output jacks will automatically produce a recording output during reproduction of
a progmm through the receiver and will provide the tape recorder connected to these jacks with a
recording signal. If you wish, you may monitor the program information that is being recorded
[provided the stereo tape recorder you are using has tape monitoring facilities, 3-head machine] by
simply setting the MONITOR switch on the receiver to the "A" position.
1
IMPORTANT: Make sure that the DUBBING switch is set to the SOURCE position during record
or playback.
For playback from the tape recorder, set the MONITOR switch to the "A" position if you used the
TAPE A - PLAY inputs on the receiver. If you used the AUX inputs for the outputs from tape
recorder "A", set the MONITOR switch to the SOURCE position, but set the Program SELECTOR
switch to the AUX position for playback.
SIMULTANEOUS RECORDING [TWO RECORDERS CONNECTED]
To record a stereo program on two stereo tape recorders simultaneously, select the desired stereo
program source [FM, Phono, etc.]. Be sure the DUBBING and MONITOR switches are in the
SOURCE position. The TAPE A - REC and the TAPE B - REC output jacks will automatically
produce a stereo recording output during reproduction of a proglam through the receiver. If you
wish, you may monitor tape recorder "8" [providing tape recorder "B" has tape monitoring
facilities, 3-head machine] by setting the MONITOR switch on the receiver to the "B" position.
IMPORTANT: Do not set the MONITOR switch to the "A" position since this will affect the
recording level of tape recorder "B" while making simultaneous recordings on
both machines.
DUBBING OR DUPLICATING [TWO RECORDERS CONNECTED]
Refer to Figure 5 for Tape Monitoring and Dubbing Operation.
To duplicate a tape presently on recorder "A" onto a tape on recorder "B", proceed as follows:
1. Make sure the inputs and outputs of tape recorders "A" and "B" are connected to the "TAPE
A" and "TAPE B" '(REC" and "PLAY" jacks respectively, as indicated previously.
2. ('A
Set the DUBBING switch to the - B" position.
3. Play back the tape on tape recorder "A" and record it on tape recorder "B" [the output of
recorder "A" is bbing fed to recorder "8"].
4. The tape being recorded on tape recorder "B" may be monitored by setting the "MONITOR"
switch to the "8" position.
IMPORTANT: During this procedure, do not set the Monitor switch to the "A" position.
To reverse the recording procedure [duplicating a tape on recorder "B" onto a tape on record-
er "A"], simply set the DUBBING switch to "B - A". The tape being recorded on recorder A
may be monitored by placing the MONITOR switch in the A position.
IMPORTANT: During this procedure, do not set the Monitor switch to the "B" position.
21
Monitor switch may be in
DUBBING FROM RECORDER "8" or "SOURCE" position
A TO RECORDER B but not "A".
DUBBING FROM RECORDER
B TO RECORDER A Monitor switch may be in
"A" or "SOURCE" position
but not "8"
FIGURE 5
PLAYBACK [TWO RECORDERS CONNECTED]
For playback from either tape recorder, simply set the "MONITOR" switch to "A" for playback
from tape recorder "A", or to "B" for playback from tape recorder "B".
8- TRACK TAPE PLAYER OPERATION
('AIJX" position
For playback from an 8-track stereo tape player, set the SELECTOR switch to the
in order to select the "AUX" inputs on the receiver [assuming the tape player has been connected
to the "AUX" inputs].
MICROPHONE OPERATION
((MIC" input jack for connection of left and right channel microphones
This receiver has a Stereo
which can be used for mixing with any other program source. This allows you to sing-along with
misic from a program source or to make announcements, etc. However, the output of the micro-
phone[s] cannot be recorded.
When using two microphones, you will need to connect them to a 3-conductor phone plug [the
type used by stereo headphones]. A single microphone with a 2-conductor phone plug may also be
plugged into the "1yfIC" jack, which will connect it to the left input channel in the receiver. Micro-
phones used should have an impedance between 600 and 10 K ohms [dynamic type] for best
results.
To adjust the microphone input level for one or two microphones connected to the "MIC" input
jack, simply rotate the "MIC-LEVEL" control to the right [clockwise] to increase the microphone
level and to the left [counter-clockwise] to decrease the microphone level.
NOTE: If the microphone is being used in the same area as the speakers, feedback [evidenced by
a "howling" noise] may occur as the "MIC-LEVEL" control is increased. If this should
happen, reduce the setting of the "MIC-LEVEL" control or set the "SPEAKER MODE"
switch to one of the remote speaker settings so that the microphone and the speakers are
not in the same area.
22
BASS AND TREBLE TURNOVER SWITCH ACTION
Figure 6 shows how the Bass and Treble Turnover Switches will affect the action of the Bass and
Treble controls when the controls are set at maximum or minimum.
Bass Tur