Operating Instructions MA 53
Geba_MA53_e_13a.doc
17 851 430/3 11/11
Notice that the masking sound is continuously presented for effective
masking. You can interrupt the masking signal by pressing the corresponding
interrupter key
or
↔.
To mask when performing bone conduction testing, place the headphone on
the opposite ear so that the receiver is at the correct height (the sound output
grid
exactly faces the ear canal). Adjust the headband of the headphones.
The receiver on the side where the bone conductor is placed should sit directly
on the cheek bone.
The marking for air conduction with masking should be done with the
symbols
= the right side and
■ = the left side on the audiogram form. T
he
marking for bone conduction with masking should be done with the symbols
[ = the right side and ] = the left side on the audiogram form.
4.4.4 Automatic masking:
With the manual masking, as described before, you have to readjust the
masking level every time you change the test signal level. The MA 53 has a
tracking feature for easy masking.
Adjust for the test signal using the level control knob
or
↕, then with the
opposite level control knob
or
adjust for the corresponding masking
level.
Now press the TRACK button
. The
masking level is automatically changed if
you adjust the test signal level. (e.g. if the
test level was 30 dB and the masking level
50 dB and you change the test level to 45
dB the masking level is automatically
adjusted to 65 dB).
Picture 15 MA 53 display for bone
conduction with masking and enabled
tracking function
Содержание MA 53
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