Werbung
Maintenance Instructions
Before undertaking any checks, inspection or maintenance of the unit, the driving surfaces and the heads must be cleaned with isopropyl alcohol.
Important!
Insure that in no case oil seeps onto the running surfaces of the drive mechanism.
in order to obtain good and exact measuring results and in order to stick with the
correct standard ratings, all parts should be cleaned and lubricated as prescribed.
Take-up tension
Spring scales,
measurement
bobby
adjustment.
Measurement using the bobby
on the right and left hand take-up
drive disks.
Torque
>0.6 Nem,
> 1.6 Nem
(torque
> 60 pcm,
< 160 pcm).
The clutch cannot
be adjusted; if
necessary the
clutch arm must be
item.|
Designation
Function|
Auxillaries
Description
Ratings
Remarks
—_—
1
Height adjustment,
Universal test
The record/playback head must
| The tape must seat | With the > button depressed, it
redord/playback
cassette
be at right angles to the contact
freely in the tape
is nct possible to tilt the
and erase heads
(prism cassette)
surface. Once this adjustment is | guides onthe
cassette.
complete, execute eletrical
heads. The tape
adjustment, item 1.
must not catch on
the tape guides.
4
2
Pinch roller
Spring scale
Attach the spring scale to the
F=3.5N+0.7N
If values outside the tolerances
pressure
(contact
pinch roller arm at test point
(350p + 70p)
are found, change the spring, as
pressure scale
(fig. 1). Raise the pinch roller
no adjustment can be made
5 N (500 p)
completely and slowly allow to
here.
return to the capstan. Read the
force registered on the scale
when the pinch roller begins to
rotate.
pa
4
3
Axial play in the
Set the rear bearing adjusting
Axial play
Secure and protect the adjus-
flywheet
screw to the correct
0.1to03mm
ting screw with paraffin.
tension.
Rewind time for C 60 cassette
less than 85 sec. at nominal
drive disk.
shee
Adjustable at the right take-up
automatic shut-off
<< and
A>
8
Tape speed
Pitch variations
Cassette 2
A>
3150 Hz test
cassette.
Pitch variation
measurement
instrument.
off mechanically at the end of the
tape, in all operational modes.
Play test cassette at the middle
of the tape. Adjust the speed
so that the drift indicator
registers 0%
replaced
torque
cassette
the right tape reel scale.
> 0.4Nem,
<0.65 Nem
(40 pcm to
65 pcm)
cassette
measured at the left-up drive
0.015 to 0.045 Nem
disk.
(1.5 to 4.5 pem)
aes
Pe eee ret be
|
7
Tape end
The tape drive mechanism is shut]
Shut-off time
t<5sec.
4.76 cm/sec.
+0.8%
has come to a stop.
The mechanical impulse
transmitter is triggered at the
right take-up drive disk once it
Adjustment in the
motor housing.
Both tapes as
Tolerance <0.5%
Tone generator,
Record a test tone (3150 Hz)
Mensured S 0.2 %,
<< and
pitch variation
using the pitch variation
linear
0.4%
measurement
instrument as a tone generator
instrument
Measurement is then made with
unrecorded SM
the pitch variation instrument
cassette
during playback (measuring
flutter).
ae D
|
Pitch variations
Tone generator,
Measurement is then made with
Mensured
pitch variation
the pitch variation instrument
0.14%,
Cassette 1
linear
$0.3 %
measurement
during playback (measuring
instrument
flutter)
unrecorded SM
cassette
es, es rel
__1
equal as possible adjust.
Test at start and end of tape
Test at start and end of tape
15
Electrical Measurements and Adjustment
Correct mechanical adjustments are a prerequisite for succesful completion of electrical test measurements.
Demagnetize heads and capstans prior to testing.
If not otherwise indicated, all tests are carried out with the noise suppression circuit switched out.
Point | Check
Function
| Aids
Description
Nominal value
Notes
1
Rec/PB head
>
AF-Voltmeter,
Connect AF voltmeter at
Ua = greatest
After adjustment, secure
swinging into
Rocker cassette
line out jack. Play test tape
maximum value
the rocker adjustment
position for
10 kHz / -20 dB
and use the rocker adjustment
screw with enamel paint
both tapes.
screw to set the rec/PB head
for maximum output voltage.
Connect both in parallel
2
Adjustment of
>
VTVM,
Connect the VTVM to B 6 of
Ua= 610
mV
Adjust tape 1
Playback level
Dolby level
the HIGH COM module play
+10 mV
with
R2L and R2R
for both tapes.
cassette
the Dolby level cassette and
Adjust tape 2 with R 1L
measure each channel
andRiR
400 Hz/0 aB.
separately.
3
Measurement of
>
VIVM,
Connect the VTVM to the
The values
Measure both the tapes
the playback
DIN-reference
Line-out-socket and measure
should be within
individually and separately.
frequency
tape for CrO.
the individual frequencies.
the tolerance
response for
field.
both tapes.
Refer to Fig. 1.
Page 4
4
Adjustment of
Record
AF-Generator
Connect AF-generator to
Adjust so that
Adjustable with R 7L and
level indicators
AF-voltmeter
"line in" jacks. Adjust input
yellow led lights.
R7R,R8LandR8R.
at drive 2.
voltage, f = 400 Hz, with level
In central position.
controls so that B6 on the
HIGH COM module gives a
level reading of 600 mV.
5
Adjustment
AF-generator
Values within the
Note: more bias at rec/play
of bias
AF-voltmeter
admissible range
head: less treble, less bias at
illus. 1
rec/play head: more treble.
Page 4
lym too low
"™\
~
'
J
lvm too high
a
a
Adjustment
Free metal tape
Approximate
Adjustable with R 3L and
for metal
cassette, charge
value:
R 3R for metal tape.
AC 711 or BASF
Uym approx.
Metall IV.
9 mV at TP1/TP2
corresponds to
U approx. 20.5 V
at TP3.
Recod||/
ec... |
AF-generator to "line in" jacks.{ [~
=
ar
eee
b
Adjustment
4
Free CrO2
AF-voltmeter to TP1/TP2
Approximate
Adjustable with R5
for CrO,
ss <
cassette, charge
or TP3.
value:
ie
$4592A or Agfa || Adjust bias so, that
Uy
Approx.
and
Stereochrom HD
recordings of 333 Hz and
5.4 mV at TP1/
on
12.5 kHz (level — 26 dB at
TP2 corresponds
at
333 Hz related to HIGH COM
to U approx.
drive 2
mark) give the same level
12.3 V at TPS.
—
"TR—--—--—--—----4
reading when played back.
nal
c
Adjustment
Free Fe2O3
Approximate
Adjustable with R6.
for Fe203
cassette, charge
value:
R 723 OG or
Uym © approx.
BASF Ferro
3.2 mV at TP1/
LH Super
TP2 corresponds
to U approx.
7.5 V at TPS.
16
Werbung
