Dual C 812 Manual page 12

Modulation of the tape recording is by means of the pair of
regulators (19). Both stereo channels can be adjusted separately
— but also together by means of the slip clutch. The correct
level of modulation can be checked with the modulation instru-
ment (18). The quasi peak value display permits optimum tape
recordings.
Recording is correctly modulated if, during the loudest passages
of the program, the indicator deflects just as far as the O dB
mark (beginning of the red range). Brief overshoot of the 0 dB
mark does not affect the recording quality.
If the recording level has been set too low, the full dynamic
range of the tape is not being utilized. Overloading can produce
audible distortion.
Starting and Recording
When the PAUSE key (10) is pressed again tape movement
commences and the recording is started. Recording may be
started without the use of the PAUSE key, but this is not rec-
ommended. For immediate starting of the recording mode (4)
the record key must be kept depressed until the » (7) key has
been depressed.
The points to be borne in mind when recording from the various
sources are detailed in the following sections.
Copying from Records
There are two ways in which the turntable can be connected
to the unit:
1. Connect both the turntable and cassette deck to a stereo
amplifier or receiver and switch the program selector switch
of the receiver (amplifier) to PHONO.
2. To connect the turntable directly to the cassette deck proceed
as follows:
Turntables whose cartridge leads have cynch plugs are con-
nected to the LINE INPUT jacks (black = right channel,
white = left channel). Turntables whose cartridge leads have
DIN plugs are connected to the REC/PB jack. For a player
with a piezo-electric (ceramic or crystal) cartridge this is all
that is required. For a turntable with a magnetic or dynamic
cartridge the Dual TVV 47 head amplifier is required. In this
case, you will also need the Dual adapter, (part No. 262483)
if your turntable has cynch cartridge leads.
Recording Broadcasts
If the cassette deck and a tuner/receiver are connected to a
HiFi amplifier, you can record audio programs without changing
the cable connections.
If you should wish to connect a tuner or radio directly to the
cassette deck, this can be done by way of the LINE INPUT
jacks in the case of audio cables with cynch plugs (black = right
channel, white = left channel) and by way of the jack REC/PB
in the case of audio cables with DIN plugs.
Recording from Another Recorder
If you wish to record on your cassette deck from another tape
recorder or cassette recorder, you can do this with the audio
cable included with the cassette deck. Connect the unit from
which the recording is being made to the REC/PB jack. If,
however, you wish to make a recording from your cassette
deck to another tape deck or cassette deck, it may be neces-
sary to connect the dubbing lead (Dual part number 226 818)
"to the connecting jack of the recording deck.
When making connections via the cynch jacks, always connect
the audio cable to the LINE INPUT jacks of the recording unit
and to the LINE OUTPUT jacks of the unit from which the
recording is being made.
Microphone Recordings
The HiFi stereo cassette deck is fitted with a jack for low and
medium impedance microphones with values between 200 and
1000 Ohms and a 6.35 mm @ (1/4 inch) coaxial plug.
For this we recommend the Hi Fi-Electret capacitor microphones
Dual MC 304 and Dual MC 316.
The microphone connected to jack (21) automatically records
on both tracks.
Stereo microphone recording is possible by means of the 5-pole
DIN jack.
14
Erasing
Technical Data
Drive
The precision DC motor is fitted with an integrated frequency
generator and modern control IC for speed regulation. The
dual decoupling motor suspension prevents propagation of
vibration and running noises.
A precision- made flat belt drives the capstan and thereby plays
its part in the overall excellence of the wow and flutter charac-
teristics. The tape take-up drive receives its torque via a second
belt direct from the motor so that disturbances such as differen-
ces in cassette winding have no effect on the tape transport.
For the fast wind facility a functionally reliable gear drive is
used. This guarantees trouble-free winding even for older cas-
settes.
An electronic circuit continuously monitors tape movement
and prevents formation of loops in the tape. At the same time
it also provides the signals for auto stop. This function is inde-
pendent of the cassette or tape switching foil.
Head
The built-in 2/4-track M & X sound head provides excellent
magnetic properties for recording and playback in conjunction
with high resistance to wear.
Compact Cassette System
Your HiFi stereo cassette deck uses a 2/4-track format. Four
tracks are provided across the full width of the tape so that two
stereo tracks are available in each direction of play and thus
the tape length is used for double stereo playing time.
Cassettes recorded in stereo on your cassette deck can also be
played on mono cassette recorders. That is to say, stereo casset-
tes are fully compatible with mono cassettes.
Maintenance and service
From time to time it is desirable to clean the heads, capstan,
pressure rollers and tape guides. For this purpose, the cover (3)
can be removed (Fig. 3). For cleaning use a linen cloth or cot-
ton swab (e.g. O-tips) moistened with alcohol. Never use metal
instruments or touch the head surface with your fingers. The
pressure capstan should be cleaned with a dry cloth which does
not produce any fluff.
Since all the points that require lubrication have been generously
supplied with oil your recorder will work for many years under
normal conditions without trouble. Please do not try to lubri-
cate the recorder yourself. Special lubricants are needed and
lubrication and other kinds of service should only be provided
by a qualified technician or an authorized factory service agency.
Correction of Faults
If your cassette deck should give any trouble please check
whether the cause may perhaps lie in incorrect operation. The
following table may be of help. In the case of any faults which
appear inexplicable your HiFi dealer or the nearest Dual ser-
vice operation should be consulted (* possible cause or correction
of the fault).