Nagra PORTABLE ANALOGUE AUDIO TAPE RECORDER Instruction Manual - page 13

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 are correct. 

NOTE:  This only indicates the presence of a correct signal being fed to, or coming from the head, 

and does not guarantee correct recording of the signal. This should be checked by 

switching the modulometer to PILOT playback (this does not function in the RECORD 

mode).  

16. SPEED AND POWER INDICATOR 

This rotary "SASS" type indicator gives a quick visual indication that the machine is functioning 

correctly and will indicate a white segment when this is the case. It will turn black whenever any of 

the following conditions occur: 

a.)  The power supply voltage (batteries or external) becomes insufficient for correct 

operation of the machine. 

b.)  The motor current reaches its maximum limit, in this case voltage and speed stabilizer 

circuit A22 requires the motor to run faster, but this is not possible because the automatic 

current limiter circuit has been activated. (If this occurs during normal operation, then 

contact your nearest NAGRA agent.) 

c.)  WOW & FLUTTER is out of tolerance. (Contact NAGRA agent). 

Thus, when a white segment is indicated, the operator can be absolutely sure that the power supply 

is sufficient, that the motor current is correct, and that the tape speed is within tolerance. 

17. HEADPHONES OUTPUT 

This 1/4" jack type socket (type 297) is the headphones output socket accepting headphones with 

an impedance of anything from 50 Ohm to 600 Ohm. (Optimum value is 200 Ohm). 

18. HEADPHONES VOLUME CONTROL 

This small potentiometer is adjustable using a screwdriver and adjusts the level fed to headphones 

output connector (17). 

Position 1 is the minimum and position 6 is the maximum. 

19. REEL FIXING NUT