Calibration Properties - Interacoustics AT235 Mode D'emploi

AT235 Instructions for Use - US

5.2 Calibration Properties

Calibrated Transducers: Contralateral
Accuracy:
Stimulus Presentation
Control:
Impedance Calibration Properties
Probe tone
Compliance
Pressure
Barometric pressure
Earphone:
Probe system:
General
Reflex Frequencies:
Contralateral Reflex
and Audiometer Tone
Levels:
Ipsilateral Reflex Tone
Levels:
Pressure
measurement:
Compliance
measurement:
Reflexes:
Frequencies:
Level:
Distortion:
Range:
Temperature
dependence:
Pressure dependence:
Reflex sensitivity:
Reflex artifact level:
Temporal reflex
characteristics:
(IEC60645-5 clause
5.1.6)
Range:
Safety limits:
The barometer
pressure chances
influence on the
impedance
measurement in the
specified range (97300
– 105300 Pascal).
Telephonics TDH39/DD45 with a static force of 4.5N
0.5N and/or EARtone 3A and/or CIR insert phone
Ipsilateral Earphone: is integrated in the probe system
Probe frequency transmitter and receiver and pressure
transducer is integrated in the probe system
Generally the instrument is made and calibrated to be
within and better than the tolerances required in the
specified standards:
±1%
3 dB for 250 to 4000Hz and 5 dB for 6000 to 8000Hz
5 dB for 500 to 2000Hz and +5/-10 dB for 3000 to
4000Hz
5% or 10 daPa, whichever is greater
5% or 0.1 ml, whichever is greater
ON-OFF ratio ≥ 70 dB
Rise time = 20 ms
Fall time = 20 ms
A weighted SPL in Off = 31 dB
226 Hz 1%, 678 Hz 1%, 800 Hz 1%, 1000 Hz 1%
85 dB SPL 1.5 dB measured in an IEC 60318-5
acoustic coupler. The level is constant for all volumes in
the measurement range.
Max 1% THD
0.1 to 8.0 ml
-0.003 ml/C
-0.00020 ml/daPa
0.001 ml is the lowest detectable volume change
≥95 dB SPL (measured in the 711 coupler, 0.2 ml, 0.5 ml,
2.0 ml & 5.0 ml hardwalled cavities).
Initial latency = 35 ms (5 ms)
Rise time = 42 ms (5 ms)
Terminal latency = 23 ms (5 ms)
Fall time = 44 ms (5 ms)
Overshoot = max. 1%
Undershoot = max. 1%
Values between -600 to +400 daPa can be selected in
the setup.
-750 daPa and +550 daPa, 50 daPa
Admittance can vary inside: ± 4%
The pressure accuracy is: ±10 daPa or 10%, whichever
is greater.
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