Audio Traveler AA222, Operation Manuals, Page: 88 / 141

AA222 Operation Manual Page 88
probe system for reflex
measurements.
Reflex sensitivity: 0.001 ml is the lowest detectable
volume change.
Reflex detection: The risk of artefacts at higher
stimulus levels in reflex
measurements are minor and will not
activate the reflex detection system.
Air: Connection for air system to probe.
USB: Input/output for PC connection. An
external PC can be setup to both
monitor and control the instrument.
The control actions can be followed
on the display and the operation
panel. Online communication can be
selected, where the measured data
will be sent to an external PC.
Keyboard: Connection for external keyboard,
standard PC type.
Tolerance
Probe tone: frequency accuracy better than 2%
Insert earphones: frequency accuracy better than 3%
Super-aural earphone: frequency accuracy better than 3%
THD
Probe tone: THD is less than 3%
Insert earphones: THD is less than 5%
Super-aural earphone: THD is less than 2.5%
Attenuator
Range: 0 to 130 dB in 1 or 5 dB steps.
Typical range is
–10 to 120 dB HL.
Range is individual for different
modes
– see table 1.
Test Types
Manual Audiometry: Manual control of all functions.
Automatic Audiometry: Auto threshold according to ISO
8253-1 (Patient controlled Hughson
Westlake). Threshold is determined
by the activation of the patient
response.