uher SG 631 Logic, Руководство по эксплуатации

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PHONO input and level controls and © must be kept turned up full
in the highest part of the scale range. If you have difficulty in solving
such connecting problems, kindly consult your audio dealer.
4.2 Power Supply
When first connecting the SG 631 LOGIC, particular attention should be
given to the instructions and comments found in sec. 1.4. Never forget
to disconnect the power supply lead from the mains power outlet
before changing the fuse or resetting the voltage. The plug must also
be taken out of the mains outlet before cleaning the SG 631 LOGIC
with a moistened cloth.
If the power supply is completely in order, the level meter and the
function indicator above the STOP key must light up once the POWER
switch (18) is pressed. addition, the function indicators for "A" or "B"
monitoring and for reel-size "5-7" or must light up, according
to the control settings. The D.C. fuses, which are not accessible from
outside the machine's housing, should be changed only by a service
technician as the cause of the defect must first be removed.
Even extremely brief overloading and internal short-circuiting are
detected by an electronic guard circuit that immediately switches off
the power supply. Pressing the POWER button
off and on again will
switch the power supply back on if the D.C. fuses are still intact.
4.3 Preparing to Record
All preparatory steps prior to actual recording should be carried out
with great care. They will be easier to remember if they are always exe-
cuted in the same order.
After first mounting the NAB adapters and/or the reels, then threading
the tape (see sec. 1.6), make certain that the reels are securely locked
onto the spindles and that the right switches for tape type (switch )
and reel-size (switch @) have been activated (see also 3.21 and
3.24).
In selecting the tape speed, the frequency response of the input source
to be used and, under certain circumstances, the duration of the re-
cording, should be decisive. The highest frequency an FM station can
transmit is
kHz. reality, however, broadcasts rarely exceed kHz.
The highest frequency obtainable from a high-quality microphone is
approximately 20 kHz. The same is true of new, high-quality phonograph
records. As speed deviations between two tape recorders may be
balanced out - but also added together - in dubbing, it is advisable
to set the recording machine at the highest tape speed whenever possible.
The advantages of doubling tape use or of stereophonic sound, for slide
showings or film dubbing, which may be achieved through quarter-
track recording are juxtaposed by an improvement of approximately
3 dB in the signal-to-noise ratio and the possibility of editing (splicing)
the tape when recording with the half-track stereo configuration.
Before starting to record, careful thought should given to all of these
factors and, if necessary, test recordings made for evaluation.
4.4 Making Record Level Test and Starting to Record
Making a record level test means adjusting the record level - without
tape motion - before starting to record. The test can be made upon
simply pressing the RECORD key lightly. A more practical procedure
is, however, to actuate the RECORD , PAUSE © and START keys
one after the other once the tape has been threaded and wound onto
the take-up reel past the switching foil (see sec. 1.6). The SG 631 LOGIC
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