Sansui TU 777 Troubleshooting guide

SANS-00184
OPERATING INSTRUCTIONS
& SERVICE MANUAL
SOLID-STATE AM/FM STEREOPHONIC TUNER
SANSUI TU.777
SANSUI ELECTRIC COMPANY LIMITED

Thank you for purchasing the Sansui TU-777. In doing so, you
have made a wise choice, one that promises you many delightful
years of rich stereo enjoyment.
Model TU-777, incorporates the very latest in circuitry design,
including a new FET front end for increased FM sensitivity, high
stability and low distortion. It also features a dignified black
faced front panel, symbolic of all Sansui high-grade sound equip-
ment. Before leaving the Sansui factory, this model was tested,
inspected and certified to be in perfect working order.
To keep it that way, it is imperative that you read the Opera-
tion section of this manual thoroughly before attempting to in-
stall and use the tuner. Since this manual also contains other
helpful information on checking and servicing the tuner, and in-
stalling it in a custom-made cabinet, you will undoubtably want
to retain it for future reference. Again, our sincere thanks for
purchasing the TU-777 and our best wishes for many years of
trouble-free stereo enjoyment.
CONTENTS
OPERATION SECTION
Switches & Controls: -i2vivissaticedi tis Mon tear ete sakes’ 3, 4
Anterina Contection: cecchatevigeced estat hots sean adeee ned 5, 6
Amplifier Connection: ¢02) hie os sepaccdsen esa bid tera terior dyaees 6
OpetatiOnt o5..50 nent tee tree es ea tae eee est 7
General Maintenance se: i5e5-so055 se. Saeenioueieat cupedacs 7,8
Specifications/Characteristics .......... 0... :ce ee eeecee eee eeeene 9, 10
SERVICE SECTION
General Troubleshooting Chart ................. 2. cee ee senna 11, 12
Disassembly Procedure.................cccccccceeeseeeeeeseeseeees 13
Dial. Mechamisint sc.cecedetietet even Stone es eee eo Sea vs 13
Custom Mounting ............. ccc cece cece cee ce cece cane sec eeenees 14
‘Lest Poitits Charticceois test artasse eta reaeeweedechieienditwesnnets 15
Alignment Procedure
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PMEMULTIPLER: tacicimersuccioaigah cede viestortastands alee 17
PM i aria ness te Gh adele en np aa ene caMencgsaet aa aeaN 18
Printed-Circuit Sheets & Parts List ............ 19, 20, 21, 22, 23
Biéek Diagram \cdisvisscvss cath detec dueeuc aden caSddsaas bathe 24
Other Parts & Theiv Pusition on Chassis .................. 25, 26

SWITCHES & CONTROLS
FM STEREO
POWER MUTING — NOIS!
Power Switch
The TU-777 goes on when POWER switch
lever is set to ON position,
Muting Switch
Eliminates interstation tuning noise when select-
ing FM stations. It should be used sparingly,
particularly if the tuner is located in a weak signal
area. When you want to receive a weak station,
this switch should be kept off.
FM Stereo Indicator
Iluminates
whenever
the
tuning
dial
passes
a
station
broadcasting
an
FM-MPX
program.
Does
not
light
up
for
regular
FM
monaural
broateasts.
Power Indicator
Lights
up
whenever
the
tuner
is
receiving
cur-
rent.
Remains
lit
as
long
as
the
Power
Switch
is
On.

LS
STS
SS
SS
— ~~ Dial Scales FM Antenna Local-Distant switct,
For more convenient tuning, the TU-777 features
a rounded dial window. The outside dial corre-
sponds to the FM band, the inside dial to the AM
band. Both bands share a single dial controlled
by the Tuning Knob. AM Ferrite bar antenna
Antenna terminal
—— Tuning Knob
Use to select both AM and FM stations. Be sure
to watch the Tuning Indicator when using this
control for pinpoint station accuracy.
—- Function Selector
Allows the following selections to be made:
AM: for ordinary AM band broadcasts
FM MONO: for FM band monaural broadcasts
FM AUTO: for both monaural and stereophonic
FM band broadcasts. Tuner switches automatic-
ally to either signal depending on what is being
broadcast.
FM STEREO: for FM stereophonic broadcasts
exclusively. Use if stereo signal is too weak and
automatic switching is unstable in the FM AUTO
position.
AC-Outlet
Tuning
Indicator
Power
fuse
Aids
in
pinpointing
stations
with
the
Tuning
Knob.
Stations
are
accurately
tuned
when
the
needle
in
this
window
swings
as
far
to
the
right
as
possible,
but
not
necessarily
to
“5”.
This
move-
ment
may
vary
from
station
to
station.
Output
MPX Noise Canceler
Use to depress disturbing noise when listening to
an FM stereo broadcast, but only if disturbing
noise occurs. In weak signal areas it may some- Output level adjustment Control
times impair the separation of stereo sounds.
High frequency sounds are not affected when this FM Stereo separation adjustment Control
Switch is on.
GND grounding terminal

ANTENNA CONNECTION
AMPLIFIER CONNECTION
UNSWITCHED:
MAX 150V)
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RIGHT CHANNEL LEFT CHANNEL
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CONTROL AMPLIFIER
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ANTENNA CONNECTION
The quality of reception that can be expected from
the TU-777 is largely dependent on the correct posi-
tioning and use of antennas. The following proce-
dures are recommended for noise-free reception.
Built-in AM Ferrite Bar Antenna
This sensitive antenna, located on the rear panel of
the tuner, is usually adequate for strong AM recep-
tion. To use, pull it down and away from the back
of the tuner until it comes to a stop halfway between
the top and the bottom of the tuner.
Outdoor AM Antenna
In ferroconcrete buildings or in areas remote from
the broadcasting station, the built-in ferrite bar
antenna may be inadequate for strong AM recep-
tion. An outdoor antenna then becomes necessary.
This can be accomplished by connecting the PVC
wire accompanying the tuner to the antenna termi-
nal marked AM-A on the back panel. Run this wire
to an antenna that has been installed outdoors and
away from the building. At the same time, the unit
should be grounded. Position the outdoor antenna
where reception is strongest while actually receiv-
ing a broadcast. And, for reasons of safety, be sure
to attach a lightning arrester to the outdoor an-
tenna.
FM Antenna
Where FM broadcasting stations are near and FM
signals are strong, satisfactory FM reception can be
obtained by using the feeder wire accompanying
the tuner. Connect the feeder wire to the antenna
terminals marked FM-A, and FM-A, on the rear
panel, then fully extend the wire to a T shape and
fix it to a wall or ceiling where it allows the strong-
est reception.
If the TU-777 is used in a thick-walled building or
in an area remote from FM broadcasting stations,
the indoor feeder wire antenna may be inadequate
for strong signal reception. An outdoor antenna
designed exclusively for FM reception should then
be installed.
FM antennas of the 300 ohm balanced type and 75
ohm unbalanced type can be used with the TU-777.
Connect either antenna to the matching antenna
terminals on the rear of the tuner. The 300 ohm
feeder wire should be connected to the FM antenna
terminals A; and A, as in Fig. 1.
If a 75 ohm coaxial cable is used, connect the con-
ductor to the FM antenna terminal A, and the
shielding wire to the terminal G as in Fig. 4.
NOTE: FM sensitivity cannot be raised simply by
lengthening the antenna. Adjust the antenna’s
height and direction while actually listening to a
broadcast for the best reception.
AMPLIFIER CONNECTION
The TU-777 has been provided with two cords for
quick and convenient connection to an amplifier.
One is marked L and corresponds to the left stereo
channel, the other is marked R and corresponds to
the right. If the TU-777 is to be used with Sansui’s
matching AU-777 amplifier or any other Sansui
amplifier, insert the pin plugs of each cord into the
amplifier inputs labeled TUNER or AUX respec-
tively. Be sure in either case, that cord L is insert-
ed into the left input and R is inserted into the right
input. If the TU-777 is to be used with an ampli-
fier other than Sansui, the same procedures general-
ly hold true, but it is best to check the manufac-
turer’s instructions to be sure.

OPERATION
GENERAL MAINTENANCE
RADIO PROGRAMS
To receive AM broadcasts:
1. Turn the Function Selector to AM
2. Select the desired AM station on the AM dial
with the Tuning Knob. It is properly tuned when
the needle in the Tuning Indicator woves as far to
the right as possible.
To receive FM broadcasts:
l. Turn the Function Selector to FM MONO for
regular monaural broadcasts, to FM AUTO for both
monaural and stereo broadcasts, and to FM ST-
EREO for only stereo broadcasts.
NOTE: If stereo reception is unstable with the
Function Selector in the FM AUTO position, turn
to FM STEREO.
If too much disturbing noise accompanies a stereo
broadcast in either FM STEREO or FM AUTO
positions, first switch the NOISE CANCELER on,
and if the noise is still too disturbing, turn the Func-
tion Selector to FM MONO to hear the same broad-
cast monaurally.
2, Select the desired FM station on the FM dial
with the Tuning Knob. It is properly tuned when
the needle in the Tuning Indicator moves as far to
the right as possible. The FM Stereo Indicator il-
luminates automatically whenever an FM stereo
broadcast is being received.
3, When too much interstation noise is during tun-
ing, turn the Muting Switch to its On position.
4, It is best to adjust the output level of the tuner
to match that of other sound equipment being used
with the amplifier. This can be done by turning the
LEVEL ADJ. control on the rear of the panel to
either a higher or lower level.
GENERAL
MAINTENANCE
FM Stereo Separation
If
the
channel
separation
during
FM-MPX
stereo
reception
is
inadequate
or
excessive,
turn
the
screw
marked
MPX
SEPARATION
on
the
rear
of
the
tuner
for
natural
proportions.
Never
attempt
to
adjust
it
without
reason
however,
as
it
has
been
properly
adjusted
and
tested
prior
to
leaving
our
factory.
SEPARATION
Local-Distant
Antenna
Switch
This
switch
helps
to
adjust
the
tuner
to
the
strength
of
FM
signals
in
whatever
area
it
is
being
used.
Set
it
to
DIST
if
you
live
in
an
area
where
FM
signals
are
weak.
If
you
live
near
broadcasting
sta-
tions
where
there
is
danger
of
interference
between
stations,
set
the
switch
to
LOC.

Where to Place
Since transistors are extremely susceptible to heat,
the TU-777 has been designed to diffuse heat
through the top and rear of its case. Therefore,
special consideration should be given to where it
will be used before installing the tuner. It should
not be operated in a place where it is exposed
directly to the sun, near radiators or other heat-
generating sources, and it should never be mounted
in an air-tight cabinet. Finally nothing should be
placed on top of it.
AC Outlet
The TU-777 has ben provided with a 150VA power
outlet on its rear panel. It can be used an AC power
source for other components such as a turntable,
but care should be taken not to use it for any com-
ponent that exceeds its 150VA power capacity.
UNSWITCHED
FUSE MAX .ASOVA
replace with Pe)
some type 1A fuse
oN
Power Fuse
If the tuner fails to operate when the power is
switched on, its power fuse may be blown. To
check, turn the fuse holder at the rear of the tuner
to the left. [fit is blown, disconnect the tuner from
its power source and replace the fuse with an
identical 1A fuse, after finding and eliminating the
source of trouble that caused the fuse to blow.
Using wire or a fuse of a different capacity as a
stop-gap measure is dangerous and should be avoid-
ed. If the new fuse blows when the power is
switched on again, contact your nearest Sansui
dealer or our Service Section.
Level Adjustment Control
This control, labeled LEVEL ADJ. on the rear
panel of the tuner, allows the TU-777’s output level
to match that of turntable, speakers and other com-
ponents connected to an amplifier. Turned clock-
wise, it increases the output level of AM and FM
broadcasts; turned counter-clockwise, it decreases
the output level of both.
LEVEL ADJ.
Grounding
Connect one end of vinyl or enameled wire to the
terminal screw marked GND at the rear of the
tuner, attach a copper plate to the other end, and
bury it underground. Whenever an outdoor AM
antenna is used, grounding becomes necessary. In
all cases, grounding is desireable since it allows a
better S/N ratio to be obtained.
tte 7 7 J 7 V4
COPPER PLATE COPPER PLATE
BURIED UNDERGROUND. BURIED UNDERGROUND.

SPECIFICATIONS
CHARACTERISTICS
FM SENSITIVITY (1HF) & IMAGE RATIO FM SECTION
10 1 FREQUENCY RANGE: From 88 to 108 MHz
IMAGE RATIO
oo —} = SENSITIVITY:
PA | Antenna input 3002 balanced 1.44V
8 all | (S/N 20 dB, quieting)
- 1.82V (IHF)
zo) Antenna input 75Q unbalanced 0.74V j
2 2
z (S/N 20 dB, quieting)
SENSITIVITY 1.02V (IHF) :
IMAGE REJECTION: Better than 80 dB (IHF)
88 92 96 100 104 108 SELECTIVITY: Better than 50 dB (IHF)
CARRIER FREQUENCY (MHz)—~
SIGNAL TO NOISE RATIO: Better than 65 dB (60 dB
SIGNAL TO NOISE RATIO, OUTPUT
LEVEL VS ANTENNA INPUT input, 100% mod.)
ey ee Ee eee HARMONIC DISTORTION: Less than 0.8% (60 dB
: ne input, 100% mod.)
vf SPURIOUS RESPONSE REJECTION:
; Better than 90 dB
é—i5- DW SS HO IF REJECTION: Better than 95 dB
INA INPI *
—— SPURIOUS RADIATION: Less than 34 dB
Ree iach bales CAPTURE RATIO: Less than 2.5 dB (HF)
dle FM STEREO SEPARATION: 35 dB (60dB input, 100% “fg
| mod.)
rg AM SECTION
Fa FREQUENCY RANGE: From 535 to 1,605 kHz
| | 3 SENSITIVITY: 15zV (at 1,000 kHz, S/N 20 dB)
Lt SELECTIVITY: Better than 20dB (at 1,000 kHz,
| 8 b -ARRIER 60 dB input)
2. EQUENCY
_ oe MHz
Ba) -400 -200 0 +200 +400 +600
FREQUENCY DIFFERENCE (KHz) —=
S/N & DISTORTION DISCRIMINATOR
— I r
0.3)
8
° Nn
WUTPUT VOLTAGE {VV}
2
&
;
FREQUENCY --- 98MHz
1 MODULATION:-100% 400Hz
3
RESPONSE (dB) -
; t
200 460 600)
}O.7MHz. eREQUENCY
DIFFERENCE - -
(KHz) H
&
+ { !
= oN
DISTORTION (%]—=
TorsToRT 1ON
oc 20 80° 100 120 i ct
40 60
ANTENNA INPUT {d8Aiv]-——
ee Nea ee a RT TE ECE A PR TS a RP NE ASL CE Ee Sa, ee Ad mee ee ORR ee ee ee Te eT

IMAGE FREQUENCY REJECTION:
Better
than
50
dB
(at
1,000
kHz)
AMPLITUDE
MODULATION
SUPPRESSION
RATIO
IF
REJECTION:
Better
than
100dB
(at
1,000kHz)
|
sob
a
ed
eam
AUDIO
OUTPUT
2V(from
0
to
2V
variable)
5%
aa
;
LOAD
IMPEDANCE:
over
10k
ES
|
LC
L
OTHER
SPECIAL
FEATURES
11
-H
spt
tpt
Circular
Dial.
Muting.
FM
Stereo
Auto.
FM
Stereo
=
OS
5
-a5-35
40-50-6070
106
ae indicator. FM local/distant Switch. Fly wheel tuning. ANTE INPUT (G8) ==
AM ferrite bar antenna. FET Front end. Function
( indicator. Audio output Adjustor. Signal Strength
= (meter). Tuning Meter. FM Stereo Noise Canceller.
FM Antenna Input for 300 ohms Balanced and 75 ohms
Unbalanced.
TRANSISTORS & DIODES
28 transistors and 1 FET
24 diodes and 1 Zener diode
POWER REQUIREMENTS
FM MPX SEPARATION
* FREQUENCY in =
POWER VOLTAGE: AC 117, 220~240V, from 50 to
60 Hz AM SENSITIVITY & IMAGE RATIO
ie eats eae
POWER CONSUMPTION: 10 VA ke alle) Aiaeel
DIMENSIONS: see ee a ae
2 i=]
Width: 1394”
Height: 614”
Depth: 131”
WEIGHT: 17.1 Ibs.
ale dk |
cy oO
i if
Ss
fo)
j i i
&
Pal ENSITIVITYS4,20dB 30%MOD
ANTENNA INPUT (dB) ———
nN
ie)
fs)
a
600 800 1000 1200 1400 1600
FREQUENCY (KHz) —-—~
*All rights reserve specifications subject to change without notice.
FM CAPTURE RATIO (IHF) AM IF SELECTIVITY
6 i Sa Cae aaa
CARRIER FREQUENCY al
' 98MHz
ae = |
a4 g
# 8
A
I
z, | &
1 pp
%5 10 20 30 40 50 60 70 80 30 100 al
percha 0 5 0 5 0
ANTENNA
INPUT
(dB)
455KHz
FREQUENCY
(KHz}-~
— 10 —

GENERAL TROUBLESHOOTING CHART
PROGRAM
AM, FM_= or
MPX reception
This section has been prepared to help you quickly and cor-
rectly determine the causes, reasons and remedies in situa-
tions where your tuner does not perform sasisfactorily. You
will note that most of the causes result from improper hand-
ling or positioning of the receiver and not from internal
defects. For situations that are not covered in this section
however, and in instances where you are fairly sure that a
breakdown in the tuner’s circuitry has occurred, please
consult your nearest Sansui dealer or our Service Center.
—.
SYMPTOM
. Constant or intermit-
tent noise heard at
times or in a certain
area.
| * Discharge
PROBABLE CAUSE
or oscillation
caused by electrical appli-
ances, such as fluorescent
lamps, TV sets, D.C. mo-
tors, rectifier and oscillator
Natural phenomena, such
as atmospheric static, and
thunderbolts
Insufficient antenna input
due to thick reinforced
concrete walls of the build-
ing or long distances from
the station
Wave interference from
other electrical appliances
WHAT TO DO
* Attach a noise limiter to the
electrical appliance that causes the
noise, or attach it to the power
source of the tuner.
* Install an outdoor antenna and
ground the tuner to raise the signal-
to-noise ratio.
* Reverse the power
receptacle connections.
cord plug-
If the noise occurs at a certain
frequency, attach a wave trap to the
ANT. input.
* Keep the set a proper distance from
other electrical appliances.
: B. The needle of the
tuning meter does not
move well.
The movement of the
needle is. one thing, the
sensitivity of the tuner is
another.
' * Tune the set for maximum signal
stength.
. The zero point of the
Regional difference in field
iC * * The unit in not at fault.
meter diverges much. intensity.
ee
aes
ial
S
asia
a
5
Deeerepeas
_
AM réception A. Noise heard at a! * This results fromthe nature | * Install the antenna for maxinum
particular time of a
day, in a certain area
or over a part of the
; dial.
of AM broadcasts.
|
B. High-frequency noise
Adjacent-channel interfer-
ence or beat interference
TV set too close to the
audio system
antenna efficiency. See “ANTEN-
NA” in the operating instructions
section.
* In some cases, the noise car be
eliminated by grounding the tumr or
reversing the power cord jlug-
receptacle connections.
* Although such noise cannot be
eliminated, it is advisable to tur: the
amplifier’s TREBLE control proje rly
from midpoint to left and switc: on
the HIGH FILTER
* Keep the TV set a proper districe
from the audio system.
—__-
TT
eee
a 7; pee

PROGRAM
FM reception
SYMPTOM
PROBABLE CAUSE
* Poor noise limiter effect
or too low S/N ratio due to
insufficient antenna input.
NOTE: FM reception is affected considerably by
the conditions of transmission by stations: power
and antenna efficiency. As a result, having
difficulty in receiving another station.
*
*
WHAT TO DO
Adjust the feeder wire antenna sup-
plied for maximum signal strengh.
If this does not prove effective, use an
outdoor antenna designed excluvely
for FM. When you use a TV
antenna for both TV and FM with
the help of a divider, make sure the
TV reception is not effected.
An excessively long antenna may
cause noise.
B. ‘‘Scratch-like’’ noise | * Ignition noise caused by Install the antenna and its lead-in
is heard. the starting of an automo- wire a proper distance from the
bile engine and/or other road or raise the antenna input as
motors described above.
C. Tuning noise between | * This noise results from the | * Turn on the MUTING ‘switch.
stations nature of FM reception. As In as much as it also reduces the
i the station signal becomes sensitivity, it should be used spar-
weak, the noise limiter ingly.
effect is also decreased.
The amplification of the
limiter, in turn, is enlarged
' and thus a big noise is
| generated.
ne “i
FM-MPX recep-; A. Noise heard during | * The service area of the | * Install the antenna for maximum
tion FM-MPX ee | aes broadcast is aay antenna input.
while not heard during | alf as much as that of the; , :
FM mono reception. | FM mono broadcast. Switch the NOISE CANCELER to
its ON position.
4
B. Clearness of channel | * Excess heat * Circulation of air is important to the
separation is decreas- tuner. Make sure that air can flow
ed during the recep- underneath,
tion.
C. The stereo indicator | * Interference * The indicator is not at fault.
goes
on
and
off.
*
Readjust
VRsos
D. The stereo indicator | * Interference
goes on and off even
though a stereo station
is not received.
The indicator is not at fault.
Readjust VRso2

DISASSEMBLY PROCEDURE
DIAL MECHANISM

CUSTOM MOUNTING
This diagram shows the size and dimensions required
for mounting the TU-777 into a custommade cabined.
Note that ample space is provided for complete air circu-
lation above and below the tuner
1. Be sure the cabinet window measures 13.8,” x 54”
mm as indicated in the diagram.
2. Place two boards on the floor of the cabinet as
ilustrated. Boards should measure 3” x 38” x 108” mm
3. Drill two holes in the bottom of the cabinet at points
corresponding to holes in the bottom of the tuner.
4, Remove the four rubber feet from the TU-777.
(Retain for future use.)
5. Insert the TU-777 into the cabinet through the window
until the edges of its front panel are flush with the
cabinet, and secure both tuner and cabinet with washers
and butterfly bolts provided.
245 %q 94h”
-210% 8434 —-—__—
Seis FRONT WIDTH OF CABINET WINDOW
1
345% 13.94 2MDTH OF FRONT PANEL
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iz
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fs) Sie x=
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xS| as =
uu wis wi
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Paps
a
9.5%”
AMPLIFIER FIXING BUTTERFLY BOLTS
270", 10-4”
MINIMUM DIMENSION
MAXIMUM DIMENSION
50%, 13 48
MINIMUM DIMENSION.
— 44

TEST POINTS CHART
v3 ane
L VReoz VREOI
OUTPUT VR6o3

ALIGNMENT PROCEDURE
Any internal parts replacemert or changes, you make in the TU-777 requires
proper adjustment again. Approprate test points and adjustments are given on
the following pages.
FM ALIGNMENT PROCEDURE
NOTE: To align, set the FM signal generator level to minimum
Turn tuning gang fully.
Center carrir wave.
Set pointer at reference mark
ADJUST
FEED OUTPUT DIAL
STEP | ALIGN | GENERATOR | siGNAL INDICATOR |SETTING | ADJUST FOR
1. IF Trans- | 10.7 MHz Sweep signal is | Oscilloscope is Primary and Best I.F.T.
former +200 kHz sent to TP: connected to secondary sides | wave from
via the 0.02pF TRaoe emitter, of Lips, Toor, Tope
ceramic and then TRao; and Taos
capacitor collector to
ground via the
0.05uF ceramic
[ capacitor
2. Discrimi- | 10.7 MHz Sweep signal is | Oscilloscope is FM S curve
nator +200 kHz | sent to 2A connected to Discriminator
via the 0.05uF | 2k via the transformer
ceramic 0.05uF Toos primary
| capacitor capacitor and secondary
3. O0.S.C. 88 MHz To antenna Oscilloscope 88 MHz O.S.C. coil Maximum
400 Hz 100% terminals and V.T.V.M. Lins
Modulation at output load
Bee 2 et
4. 0.5.C. 108 MHz To antenna | Oscilloscope 1083MHz |O.S.C. trimmer | Maximum
400Hz 100% terminals and V.T.V.M. 104
Modulation at output load
5. Repeat 3
and 4
6. “| RF Amp. | 90 MHz ‘| To antenna Oscilloscope 90 MHz Antenna coil Maximum
Circuit 400 Hz 100% terminals and V.T.V.M. Lio1, Ling and
Modulation at output load 103
7. RF Amp. | 106 MHz To antenna Oscilloscope 106 MHz Trimmer TCio;, | Maximum
Circuit 400 Hz 100% terminals and V.T.V.M. TCyoe and TCiog
Modulation at output load
8. Repeat 6 |
and 7.
~t
200 -100
KHz KHZ 0
MH:
+100 +200
KHz KHz
~200 ~100 10.7 +100 +200
KHz KHz MHz KHz KHZ
— 16 —

ALIGNMENT PROCEDURE
FM
MULTIPLEX
ALIGNMENT
PROCEDURE
1.
Do
not
attempt
to
align
the
Multiplex
Circuit
unless
the
following
equipment
is
available:
a. Multiplex Stereo Generator
b. Oscilloscope c. AC V.T.V.M. d. Audio Oscillator
e. FM Signal Generator
FEED OUTPUT ADJUST
STEP
ALIGN
GENERATOR
SIGNAL
INDICATOR
ADJUST
FOR
1.
67
kHz
Trap
67
kHz
Audio
Connect
to
V.T.V.M.
at
Lio.(MFC-A)
Minimum
Signal
TPas
TPaos
2.
“|
71
kHz
Trap
71kHz
Audio
Connect
to
V.T.V.m.
at
Lo2(MFC-B)
Minimum
les Signal TPea TPs
2 eacereneretet mee
3.
19kHz
FM
Signal
Gen.
Antenna
V.T.V.M.
and
|
Tuoi(MPT-20A)
|
Maximum
Transformer
Modulated
30%
terminals
Oscilloscope
at
by STEREO Gen. Tune to signal 01
sub-channel
4,
19kHz
FM
Signal
Gen.
Antenna
V.T.V.M.
and
|
Tuoe(MPT-20B)
|
Smaller
Transformer
Modulated
30%
terminals
Oscilloscope
at
peak
value
by
STEREO
Gen.
Tune
to
signal
Pros
of
two
sub-channel
peak
values
5.
38
kHz
FM
Signal
Gen.
Antenna
V.T.V.M.
and
|
Tios(MPT-20B)
|
Smaller
Transformer
Modulated
30%
terminals
Oscilloscope
at
peak
value
by
STEREO
Gen.
Tune
to
signal
Pros
of
two
sub-channel
|
peak
values
+
6.
38
kHz
FM
Signal
Gen.
Antenna
V.T.V.M.
and
|
Tuos(MPT-20B)
|
Channel—-R
Transformer
Modulated
30%
terminals
Oscilloscope
at
|
within
4
turn
Minimum
and
by
STEREO
Signal
|
Tune
to
signal
|
output
load
and
separation
Separation
VR
|
Gen.
channel-L
channel-R
VR(VReo1)
— {7 —

AM ALIGNMENT PROCEDURE
GENERATOR
FEED
SIGNAL
NOTE: To align, set the AM signal generator level to minimum,
OUTPUT
INDICATOR
DIAL
SETTING ADJUST
ADJUST
FOR
1.
LF.
455
kHz
Antenna
|
Oscilloscope
and
Primary
and
Best
L.F.T.
Transfor-
+30
kHz
terminals}
V.T.V.M.
at
secondary
sides
|
wave
form
mer
Sweep-generator
TPyoe
from
the Ist
LF.T. (T 302) to
the 3rd
LF.T. (Tso4)
2.
0.S.C
AM-generator
Antenna
|
Oscilloscope
and
535kHz
|
O.S.C.
Coil
Tso.
|
Maximum
533 kHz 30% terminals| V.T.V.M. at
400 Hz 30% output load
Modulation
eed eee
3. 0.S.C AM-generator Antenna | Oscilloscope and 1600kHz | O.S.C. Trimmer | Maximum
1600 kHz terminals} V.T.V.M. at cap. TCao3
400 Hz 30% output load
Modulation 2
4, Reiterate
2 and 3 is ——
ames
5. RF amp. AM-generator Antenna Oscilloscope and 600 kHz RF transformer | Maximum
600 kHz terminals} V.T.V.M. at Tso1
400 Hz 30% output load
Modulation
6.
Antenna
AM-generator
Antenna
|
Oscilloscope
and
1400kHz
|
Ferrite
bar
Maximum
circuit 500 kHz terminals} V.T.V.M. at Antenna coil
400 Hz 30% output load L301
Modulation
7. RF amp. AM- generator Antenna | Oscilloscope and 1400kHz | RF Trimmer Maximun
1400 kHz terminals | V.T.V.M. at TCeo2
400 Hz 30% output load
Modulation
8.
Antenna
AM-generator
Antenna
|
Oscilloscope
and
1400kHz
|
Antenna
Maximun
circuit 1400 kHz terminals| V.T.V.M. at circuit
400 Hz 30% output load Trimmer TCgo;
Modulation
9. Reiterate
5, 6, 7, 8
L
=10KHz 455 -HOKHz
KHz
AM IF CHARACTERISTIC

PRINTED-CIRCUIT
SHEETS
&
PARTS
LIST
FM, AM IFT F-1014
R201
R202
R203
R204
R205
R206
R207
R208
R209
R210
Rai
Rai2
R213
Rai4
Rais
R216
R27
R218
Rai
R220
R221
R222
R223
R224
R225
R226
R227
R228
R229
R230
R231
R232
3.3k0
6.8kQ
1kQO
1kQ
1kQ
10kQ
5.6kQ
1.5kQ
4700,
5.6kO
8.2kO,
222,
1kQ
6802,
220,
6.8kO
8.2kO
1kO
1kO
220,
10kQ
1kQ
1kQ
220,
1kO
1kO
680,
10kQ
10kQ
1kO
10kQ
22k
+10%
+10%
+10%
+£10%
+10%
+10%
£10%
+10%
£10%
+10%
£10%
+10%
+10%
+10%
+10%
+10%
+10%
+10%
+£10%
+10%
+10%
+10%
+10%
+10%
+10%
+10%
+10%
+10%
+£10%
+£10%
+10%
+10%
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC,
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
R233
R234
R235
R236
R237
R238
R239
R240
R241
R242
R243
R301
R302
R303
R304
R305
R306
R307
R308
R309
R310
R311
R312
R313
R314
R315
R316
R317
R318
R319
R320
— 19 —
2220,
47kQ,
18k,
12k0,
39kQ
6.8kO
100kQ
2.2k0
§60kQ,
10kO
1kO
1200
4.7kO
22k,
1.5kO
1000
68kQ,
§.6kO
1kQ
1kQ
1kQO
ka,
4.7kQ
15kQ,
1kO
1kOQ
$.6kO
15kQ
68kO
12kQ
+10%
+10%
+£10%
+10%
£10%
+£10%
£10%
+10%
+10%
+10%
+10%
+10%
+10%
+10%
+10%
+10%
+10%
+10%
+£10%
+10%
+10%
+10%
+10%
+£10%
+10%
+10%
+10%
+10%
+10%
+£10%
PREC.
PREC.
PREC,
PREC.
PREC.
PREC.
PREC,
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC,
RREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC.
PREC,
PREC.
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed