Nagra III - Function Selector and Accelerator

Page 3
employing this speed, headphones should be used for monitoring. Then when the
battery voltage falls to a level unsatisfactory for recording an alarm signal
will be heard in the phones. It is well to remember ..that batteries used
uninterruptedly for, say, an hour, will recuperate when rested for, say,
10 hours. Therefore exhausted batteries may appear acceptable during a quick
test before recording, but then collapse after a few minutes use.
To recapitulate:
If one is recording at 15" / sec. always use monitoring headphones and read
the battery meter pessimistically.
If one is recording at 7
1
/2" or 3 3/4
11
/sec . for fairly short periods, say
15 minutes, a battery test before starting should be sufficient. On the
other hand, if the recording s e ssion is of long duration, the batteries
should be checked when changing reels.
7) Pilot Signal Indicator
This is an indicator on which a white cross will appear when the Nagra is
receiving the pilot signal (N eo pilot Nagras only).
8) Accelerator Button
By pressing this button the motor speed is increased to its maximum. This can
be done during play-back for forward spooling. Although no damage will be done
by pressing the button during recording, the speed will be incorrect.
9) Function Selector Switch
This switch controls the functioning of the Nagra. It has two sets of six
positions. One set is for working on internal batteries when the end of the
switch knob marked "bat" is used as an indicator, and one set is for working
with an external power supply, when the other end of the knob, marked II ex t",
is used as an indicator.
The positions are as follows:
STOP
in the centre
TESTING to the right
In this position the amplifiers are connected but not the motor, so that the
incoming signal to be recorded can be checked. The monitoring phones are
connected to the record amplifier.
HI-FI RECORD = Normal recording position.
The phones are connected to the play-back amplifier, so that the actual
recording that has been made is monitored. Incoming signals can be mixed
from both microphone and line inputs. The level of each of these signals can
be adjusted by the appropriate volume controls. If the line input is only used,
the microphone level potentiometer should be turned fully anticlockwise to
prevent the recording of noise from the microphone pre- amplifier. On the other
hand, if a recording is made through the microphone channel only, the
position of the line input volume control is immaterial.
AUTOMATIC RECORD = Recording with automatic control of level and
attenuation of low frequencies. It is not necessary to adjust the level potentiometer
but the quality of the recording is not as good as in the position HI-FI RECORD.