SM010-3 Siemens SD 270 Operating & Service Manual Page 21
7 Technical Information
Audiometer
Audiometer type:
Type 2 (IEC 60645-1)
Type B-E (IEC 60645-2)
Frequency Modulation
Carrier frequencies:
125Hz – 8kHz as per pure tones.
Modulation waveform:
Sinusoidal.
Rising and falling symmetry:
Symmetrical on linear frequency scale.
Modulating frequency:
15.625Hz.
Frequency deviation:
+/-10%.
Speech Channel
Frequency response:
+/- 3dB from 100Hz to 10kHz electrical
Input voltage requirement at
default level to zero meter:
600mVrms at 1kHz.
Output level:
90dBSPL at 1kHz for attenuator setting of
70dBHL with level meter at 0dB
Masking Sounds
Masking sounds available:
Narrow bands at test frequencies and
Speech weighted noise
NB noise bandwidth:
Meets IEC 60645-1
Speech noise bandwidth:
Meets IEC 60645-2
Insert Masking Earpiece
Calibration method:
With 2cc coupler compliant with IEC 126
Transducers
Types and reference levels:
DD45: ISO 389-1, Table 2
E-5A: ISO 389-2, Table 1
B-71: ISO 389-3, Table 1
Static headband force:
Headphones: 4.5N.
Bone vibrator: 5.4N.
Bone vibrator calibrated:
For mastoid placement.
Sound attenuation characteristics:
ISO8253-1, Table 3.
Airborne sound from bone vibrator:
See Br. J. Audiol. 1980, P73-75
Environmental
Operating temperature: +15
o
C to +35
o
C
Operating humidity:
30% to 90% (non-condensing)
Atmospheric pressure: 700 hPa to 1060 hPa