Nagra 4.2 Portable Analogue Audio Instructions Manual

5. PINCHWHEEL LIFTER (stop + test only) 
 
6. LEVEL CONTROL (right) mic input 2 
 
7. LEVEL CONTROL (left) mic input 1 
 
These are the main level controls for the two microphone inputs.   
 
8. REFERENCE OSCILLATOR (push button) 
 
On the lower edge of the front panel, between the line and playback potentiometer and the mic 2 
potentiometer, there is the reference generator push button. When this button is pressed, a 
composite 1.1 kHz signal with a 10 kHz 9th harmonic at a level of approximately -8 dB...

 
PILOT PLAYBACK This indicates the level of the pilot signal played back from the tape. 
 
PILOT FREQ This indicates on the +4 to -4% scale of the modulometer, the frequency 
deviation as determined by the QFM frequency meter circuit (if fitted), 
between the pilot signal being recorded or played back and the 50/60 Hz 
reference. 
 
LEVEL The modulometer will indicate the level of the direct or the recorded signal 
on the decibel scale. 
 
BATT. RESERVE Indicates on the lower scale, the bold line shows...

14. MODULOMETER 
 
This meter is the visual indication of many functions and levels of the machine. The modulometer 
displays information according to the position of mode selector switch (12).  
 
The modulometer has 4 scales: 
 
1. Recording level in dB 
2. Frequency deviation in % 
3. Battery voltage (volts / cell)  
4. Compression 
 
 
15. PILOT INDICATOR 
 
This rotary SASS type indicator shows a white segment when the frequency (if the machine is 
fitted with the pilot system) of the pilot signal...

TAPE  DECK 
 
20.  SPEED AND EQUALIZATION SELECTOR 
 
This is a six position rotary switch permitting the selection of the speed and equalization of the 4.2 in 
both record and playback. 
 
 Possible settings are:  
 
 3 3/4  ips (9.525 cm/s)   
 7½  ips (19.05 cm/s)   
 15 ips (38.10 cm/s)   
 
For each of these speed selections there are two possible positions labeled I (STD) and II (LN) 
these correspond to different tape types. 
 
For best quality recordings the 15 ips speed is recommended.  
For...

The two rollers can be replaced by either the QTIM or QLEN tape measuring rollers. The QTIM is 
supplied in the place of the take-up reel tension roller as standard equipment. QLEN instead of 
QTIM is optional. (To be stated when ordering). 
 
26. ERASE HEAD 
 
This is a full track erase head. 
 
27. STROBOSCOPE ROLLER 
 
This roller comes in two versions: 50 Hz (CCIR machines) and 60 Hz (NAB machines). Using this 
roller, it is possible to check that the machine is running at the correct speed, either...

1.3 CONNECTORS  
36. MIKE 2 input 
 
                                                                                                           
 
1      = Input signal Ground 
2+3  = Balanced signal Input 
 
 
37. MIKE 1 input 
 
Identical to No 36 above. 
 
NOTE: The microphone inputs are convertible into symmetrical and floating line inputs by 
installing, in place of the microphone preamplifiers, preamplifiers type QPM-6 and using 
the corresponding potentiometer to control the input level. 
38. RX...

40 MIXER  
 
For connection to external mixing console. (connector type: T 3478 corresponding plug T 3475/1). 
 
1. Input with fixed sensitivity, 560 mV to obtain 0 dB, input 
impedance 9 k Ohm. (2.5 Vpp to obtain +4 dB) 
2. -10 V stabilized voltage, Maximum current 50 mA. Noise level < 
5 V rms. 
3. Direct amplifier output, minimum load impedance 10 k Ohm, 
output voltage 560 mV at 0 dB. This is a monitoring signal to be 
fed back to the mixer. 
4. Unstabilized negative supply voltage. Available in all...

 
44. PILOT AND CLAPPER INPUTS 
 
1. Ground 
2. CLAPPER: Clapper oscillator control input (control voltage + 4 
to 14 V) or switching on of QRR receiver by connecting to 
ground. 
3. XTAL: Internal crystal pilot generator out, 50/60Hz. 
4. PILOT IN: Pilot signal input, impedance 5 k Ohm. Input level  
0.5 – 25 V. 
 
 
 
45. LINE OUTPUT 
 
The line output of the Nagra 4.2 is on the right-hand side of the recorder. The load impedance 
should be equal to or greater than 600 Ohm. When the Line and Phones...

48. POWER PACK 
 
6 pole connector for external power supply and pilot signal output. 
 
 
 1. - BATT: Negative pole of battery compartment.  
 2. + BATT: Positive pole of battery compartment.  
 3. PILOT PLAYBACK: Pilot playback output. 
 4. SPEED CORRECTION: Tape speed correction input. 
 5.  EXTERNAL -12 to -30: Input for external power supply -12 
to -30 V negative pole.  
 6. -10 R: -10 V stabilized voltage output during record, I max 
100 mA 
 
 
 
49. FIXTURE FOR CARRYING STRAP/HANDLE 
 
50. CASE...

2.1. POWER SUPPLY 
 
All models of the NAGRA 4.2 may be powered either by an external power supply (ATN-3) or 
alternatively by internal batteries. The 4.2 will accept voltages ranging from -11 V to -30 V with 
peaks of up to -35 V. The batteries are placed in the bottom of the machine and the polarity is 
marked inside the battery compartment. Turning the two fasteners with a screwdriver or a small coin 
opens it. All the batteries MUST be orientated in the same direction as indicated on the base of the...