Maico MA 42, Руководство по эксплуатации

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Operating Instructions MA 42
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5.1.1 Pure-tone Testing
In the pure tone audiometry, the hearing threshold of the patient is measured
in comparison with the normal hearing threshold. The examination starts with
air conduction on the ear with better hearing.
Upon opening the Tone screen the following settings are displayed.
Default setting: right channel is set to air conduction pure tone and the left
channel to air conduction narrow band noise with manual masking. The
frequency is automatically set to 1000 Hz.
The audiometer provides two channels, which can be separately routed to the
left or right ear. Each channel can play back a signal and can be routed to one
of the outputs. The signal can be set for each channel independently to tone,
narrow band noise or white noise by the functional selector buttons (11) and
(15).
Select the ear to be tested by pressing the Right or Left key (9), (17) on the
control panel underneath the screen. However it is easier to select Swap by one
of the functional selector buttons (9) or (17) to switch from the left to the right
ear.
Next select the transducer to be used, headphones (Phones), insert phones
(Insert), bone conductor (Bone) or sound field speaker (Speaker) by pressing the
appropriate button (10), (16). Only calibrated transducers are selectable.
The level and frequency of each channel is displayed as a numerical value at the
top of the screen and also as a cursor within the audiogram itself.
The dB
HL
level can be changed with the attenuator knobs on both sides (1) of
the instrument. Set the level control dial to a value just below expected hearing
loss and turn down the level of the other ear.
Figure 5 Start screen