Tandberg 6 X Service Manual

Page 2

1.0

2.0
3.0

4.0

4.1

4.2

4.3

4.4

4.5
4.6
4.7
4.8
4.9
4.10
4.11
4.12
4.13
5.0

5.1

5.2

Contents

Technical xpecilication, Tandberg tape recorder
models 64x and 62x
The function of the controls ........................

The input and output terminals ......................
3.0.1 Models 64x and 62x, without 19 kHz

FM Model 64x and 62x, with 19 Ier
FM-multiplex filter
The inpvl and output terminals marked radio,

3.0.2
3.0.3

line and center channel ........................
3.0.4

The mechanism, delailed description and adiustment

The microphone inputs ........................

instruction

The operating lever ..
4.1.1
4.1.2
4.1.3
4.1.4 . . .
4.1.5 The mechanical connection far the muting switch . .
4..l6 The trip bar
The turntable assemblies .
4.2.1
«1.2.2
4.2.3
4.2.4
4.2.5

The motor switch

The eccentric segment

The pressure wheel assembly .

The tape brake .............

The supply turntable assembly

The tape light tension ........................
The brake tor the supply turntable

The take-up turntable assembly .
Horizontal and vertical alignments ol the
turntables ..................................
clutch aligments ...... .
4.3.1
4.3.2
4.3.3
4.3.4
4.3.5
4.3.6
The motor pulley ......................
4.4.1 Threading of the rubber drive belt
The speed trancrer wheel

General

Fast rewind

Fosl wind

Normal forward drive .

Neutral

Free

The lilting mechanism ..............................
The tlywheel with the capslun

The speed change mechanism .

The momentary start-stop feulure ..

The pressure pad ..................................
The automatic end stop switch .........

The revolution counter .........................

Assembllng the top cover ..........................

The electronic circuits, detailed description and

adiustment instruction

The main electronic units, block diagram
5.1.1 The record pro-amplifier ......................
5.1.2 The FM-mulllplex filter _
5.1.3 The . .
5.1.4 The playback preamplifier
5.1.5 The cathode follower

5.1.6 The center channel amplifier

record amplilier .

5.1.7 The record level indicator circuit

5.1.11 The oscillatar, bias and erase circuit ............

5.1.9 The momentary star-l.slop circuit

5.1.10 The power supply

The switching system, block diagram
5.2.1

The push-button switch

5.2.2 The s-on.s switch

5.2.3 Monaural recording or. channel 1 ar 2 .

5.2.4 Mixing during monaural recording

5.2.5 Stereo recording ............................
5.2.6 Mixlng during stereo recording ................

o.

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5.3

5.4

5.5

5.6
5.7

5.8

5.9

5.12
5.13
5.14

5.17
5.18
5.19

5.20
5.21
5.22
5.23
6.0

6.1

5.2.7 Monaural playback channel 1 or 2 .....
5.2.8 Slerea playback
5.29 Add a track ................................
5.2.10 Sound on xound ..............................
5.2.11 Echo errects

Alignment ...........

531 Demagnetizing .
5.32 The mounting plale tor the treads ....... ..
5.3.3 The adiustable tape guide ....................
The playback head ............................
5.4.1 Height alignment .......................
5.4.2 Aximvth alignment

5.4.3 laleral alignment
Adiustment and control at playback amplifiers, with

Tundberg lest tapes ................................
5.5.1 Adiustment or the playback amplihers ..........
5.5.2 Contral at the playback amplilier ..............
Adjustment of the oscillator and bias head circuit ......
The record head ..
5.7.1 Height alignment
5.7.2 Azimulh alignment
5.7.3 Lateral ulignmenl ............................
The bias head
5.8.1

5.3.2 Horizontal alignment

Height alignment

The erase head ....................................
5.9.1
5.9.2
5.9.3 lateral alignmenl .........
5.9.4 Model 62x ..................................
Adjustment of the record current (A-B test) and the

electranlc beam indicators ..........................

Height alignment . ..

Azimuth alignment

Head alignment without Tandberg test tapes ..........
5.11.1 The playback head ..................
5.11.2 Height alignment .......
5.11.3 Azimuth alignment .....
5.11.4 Lateral alignment
The record head

The bias head .

The erase head . . ..
5.14.1
5.14.2 Azimuth alignment .

Height alignment

5.14.3 Lateral alignment ..
Track central, model 64x ............................
5.15.1 The record head .......................
5.15.2 The erase head
5.15.3 The playback head . .
Track oantrel, model 62): ............................
5.16.1 The erase head
5.16.2 The
5.16.3 The playback head. .
Adiustment of the amplifiers, without Tandberg lest tapes

record head

Control of total heguency response ...........

Central at playback and record ampliriers ..... ..
5.19.1 The playback amplifier ......................
5.19.2 The record amplifier ........................
Adjustment of the FM-mulllplex liller

Adiustment of the microswitches

Vertical mounting of the models 64x and 62x ..........
Modilicallan from model 64x ta modal 62x .....

Parts list ..
6.0.1 .
6.0.2 Electrical parts ..............................
Modification from 220V 50 Hz 10 110 V 60 Hz oparclilon

Mechanical

ports

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3E
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Page 30

ts"

secondary windings are fused with slow-blow fuses.
The 245V secondary winding is connected to the
bridge rectifier B250-C75 and furnishes an the high
tension to the amplifiers, indicators and to the motor.
The 25V secondary winding is connected to the

voltage to all amplifier and cathode follower tubes.
These tubes are DC heated to prevent hum. The 6,3 V
secondary winding furnishes the AC filament voltage
to the pilot lamp and the indicator tubes.

Note: The transformer 11,1-277 and the interlock

rectifier 830-61000 and furnishes the line voltage to
the oscillator and the center channel amplifier. The
rectifier BSD-C1000 also furnishes the DC filament

system inserted in the mains cord is furnished
on tape recorders sold in certain territories to
conform with the UL approval.

H953. Rear View or tape recorder equipped with pupst motor and transformer H.t-277-6C.

5.2 THE SWITCHING SYSTEM, BLOCK DIAGRAM

OPEN WHEN ME 5 ours SWITCH t5 lN "NORMAL" P05,
CLOSED WHEN THE s~0N-s SWITCH l5 m "SON-S" Pos
CLOSED WHEN rHE s~ON-s SWIICH is N "A-a vESr~ P05 AND 30m I! AND v ARE RELEASED

O/t

OPEN WHEN VHE s~Ost swtrcu ts IN "NORMAL" P05
CLOSED WHEN HE S-ON-S SWITCH l5 m "SON-s" P05.
CLOSED WHEN THE S'UN-S SWIYCH IS IN A'E VEST" P05 AND BO'H H AND V ARE RELEASED
. .
HI LEVEL MIC. C/
LO'LEVEL A N
RECORD RECORD I PLAvaActt cArHOOE
?RE-AMP AMP 0/: Pas-AMP. L rOLLOwER o
INPU75 C? CHJ CHI CH I (2H,! OUTPUT
4% JV); on
(I\ RECORD PLAYEACK
HEAD HEAD
RECORD GAIN CONVR. PE VOLUME
CONTROL
ERASE BIAS
CLOSED WHEN tore it IS DEPRESSED HEAD HEAD CLOSED WHEN r1 ORV ' R
OPEN WHEN l AND II ARE EnHER K 05m NOR ts DEPRESSED wnH CEEHE 33:2;
L S-ON-S SWITCH IN -0
R R
DEPRESSED o ELEASED ERASE atAs .,NDRMAWR.,A_B. 1:51" AMP. WNNEL
POSIVIDN
HEAD HEAD
RECORD PLAVBACK
0/ HEAD HEAD
RECORD I RECORD PLAVBACK cAiHDDE
'"PUIS cu? enema? AMP. O\r FREEAMP a FOLLOWED?
H or 2
LD-LEYEL av;- CHZI C 2 n c 1 ~% WIFUY
A V CH 2
"LEVEL MlC RECORD OAtN oomn.
0\ PE VOLUME CONTROL
v

OPEN WHEN WE S'ONS swnca ts IN "NORMAC'POS
CLOSED wt-trN ms S'ON-t swncu ISIN"5-DN-S'POS
CLOSED WHEN WE sm-s SWIVEH IStN'As 151"? AND 30m u may ARE RELEASED

Fig. 54. The switching system, block diagram. All push-bunch: releactsed.