TANDBERG TCD 310 Service Manual

5.
ELECTRICAL
ADJUSTMENTS
GENERAL
.
NECESSARY
EQUIPMENT
—
”0
dB”
level
is
defined
as
775
mV.
Thus
—5
dB
—
2high
impedance
voltmeters
(do
NOT
use
equals
450
mV
and
—35
dB
equals
14
mV.
universal
meters).
— Frequency counter.
; .
;
;
—
Audio
generator.
—
Make
the
adjustments
in
the
order
in
which
they
are
listed
here.
Many
of
the
adjustments
require
that
previous
adjustments
have
already
been
—
Wow
meter
(required
for
wow
test
only).
correctly
made.
It
is
especially
important
that
adjustment
for
CrOg
tape
be
made
before
adjust-
ment
for
HL
tape.
—
Tandberg
test
tapes
No.
21
(1,000
Hz
speed
test),
No.
22
(3,150
Hz
wow
test),
No.
23
(6,300
Hz
azimuth
test)
and
No.
24
(1,000
Hz
playback
™
level).
— TDK C60 CHROM or equivalent chromium
dioxide cassette.
— Distortion meter.
—
Hum/noise
meter
(required
for
signal/noise
test).
—
Clean
and
degauss
the
tape
path
before
and
after
the
adjustments.
It
is
assumed
that
the
tape
path
has
already
been
correctly
adjusted
as
described
on
pages
5,
6
and
7.
—
Maxell
C60
UD
or
equivalent
HL
cassette.
Location
of
test
points
and
adjustable
components:
see
page
17
Azimuth Adjust to best
signal. Difference screw on |compromise
between the tracks: | head
< 4¢dB
1775 mV R317 (left ch.)
R417 (right ch.
Playback
c
+
1%
(990
—
1010)
Playback
S
0.2%
Measure
at
end
of
{DIN
45,507
tape.
Measure
both
peak
weighted)
in
vertical
and
hori-
45.507)
zontal
position
CrO2
Frequency
|Connect
80
-
100
kHz
Connection
is
made
Recording
counter
inductively
with
a
coil
or
a
few
to
erase
turns
of
ordinary
head
(see
wire.
Instead
of
a
comments)
frequency
counter
a
long-wave
receiver
(
tuned
to
3rd
har-
monic)
can
be
used
|
CrO2 Voltmeter [Across [28 — 32 V
Recording lerase head
CrO2
Voltmeters
[OUTPUT
|<
5
mv
lps
INPUT
sockets
open
|
Recording
|
sockets
=
CrO2
Voltmeters
[R319
(left)
[Minimum
L301
{left
ch.)
|
The
filters
prevent
Recording
R419
(right)|reading
L401
(right
ch.)
|
the
record
amplifiers
to
ground
\{2—4
V}
from
short-circuiting
the
bias
voltage
to
ground
130!
-===4
TO REC /PLAY
HEAD TO OUTPUT
OF REC AMP
cH RTS

TANDBERG TCD 310 Specifications

General

Weight	7.5kg
Track System	4-track, 2-channel stereo
Tape Speed	4.76 cm/s
Heads	1 x record/playback, 1 x erase
Type	Cassette Deck
Frequency Response	30 Hz to 16 kHz (Chrome tape)
Signal to Noise Ratio	58dB
Wow and Flutter	0.07 %
Motor	DC servo motor
Tape Type	CrO2
Power Supply	220V
Input	Line In