Operating Instruction
ERO•SCAN
®
Screening and Diagnostic Version
operating_instructions_8106556-6_EROSCAN_e_15a
44
8106556-5 02/15
Selecting the Level of Primary TonesThe intensity of the
primary tones (L1, L2) may be changed to any level between 40
dB SPL and 70 dB SPL. The level L1 will change in 1 dB
increments by pushing the
LEFT or RIGHT
arrow keys
(Display 28) and press
NEXT to move to the L2 screen.
Press the
NEXT key to set the level of L2 as with L1 above.
18.2
Setting the Averaging Time
The Averaging Time can be changed to one of four settings.
The Averaging Time will have a large impact on the time
required to perform the test and on the signal-to-noise ratio
(SNR). A 2 second average for 6 frequencies would produce a
test in about 18 seconds, which includes the Probe Check
sequence. The possible settings for the Averaging Time are as
follows:
0.5 sec., 1.0 sec., 2.0 sec., or 4.0 sec.
Press the
CHANGE
keys to select an option and the
NEXT
key to exit (Display 29).
NOTE: Longer averaging times help to reduce the noise floor
which can improve the likelihood of obtaining a passing result,
particularly with a noisy patient (like a baby sucking a pacifier)
or in a noisy environment. However, shorter averaging times
may be preferred for young children and/or uncooperative
patients.
18.3
Setting the PASS SNR Level
In order to provide a PASS/REFER determination for each test,
the PASS SNR must be set. This number refers to the number of
decibels that the DPOAE signal must be above the noise to be
considered a PASS at that frequency. The limits for the PASS
SNR are 3 dB to 10 dB. Pressing the
LEFT or RIGHT
arrow
keys will increase or decrease the requirement. This requirement
is used in combination with the number of frequencies
(discussed below) to determine an overall PASS/REFER for each
test.
Press the
CHANGE
keys to select an option and the
NEXT
key to exit (Display 30).
Display 29
Display 30
Display 28
Summary of Contents for ERO SCAN
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