ID: 1614 / ver. 210
1. If all frequencies are answered at 20dB, you will hear 1 BEEP after the test, to indicate that all frequencies
have been heard.
2. If one or more frequencies was not responded to at 20 db, you will hear 3 BEEPS and the AUT lamp will
flash, telling you that not all frequencies have been heard. Press the AUT. button to stop the flashing, and go
through the frequencies to see which of them was not heard. All frequencies that displays “20” was heard at
20 dB, and other levels tells you at what level the patient responded. If a frequency was not responded to
even at 80 dB, the attenuator display will flash when this frequency is selected.
Variable automatic test
The frequency is set to 1000 Hz and a tone is automatically given to the left ear at an intensity of 30 dB. As long as
there is no response from the patient to the tone, the intensity will increase 10 dB each time the tone is presented,
until the patient signal button is pressed. For each response the intensity is reduced 5 dB and conversely increased 5
dB when there is no answer.
When the software program has accepted the answer, the frequency is automatically changed to the next level and
the procedure is repeated until all frequencies have been tested for both the left and the right ear.
When the test is completed, the audiometer gives a beep. If some of the frequencies have not been heard, the lamp
above the AUT button will flash. Press the AUT button and check the frequencies. The attenuator display will flash for
the frequencies not heard. It is possible to conduct a manual test for those frequencies.
Please note that for safety reasons the maximum intensity is fixed at 80 dB during the automatic test.
Please note that frequencies left out will not be included in the automatic threshold tests.
SISI test: (Short Increment Sensitivity Index)
In addition to the three automatic tests the SM960-C is equipped with an automatic SISI test. The test has three pulse
amplitudes it operates at, which can be selected while it runs. The three amplitude modes are as follows:
5dB:
The test starts in this mode, and is intended only for familiarizing the patient with the test method. The patient
responses and pulses are not counted in this 5dB mode, and the mode continues until the next mode is selected, or
the test is terminated.
2dB:
This mode presents 20 pulses of 2dB increments before it continues to the 1dB mode. It counts the patient responses,
but does not store the count in memory. If the patient has responded to every pulse, or did not respond to any of
them after 10 pulses, the test will continue to 1dB mode.
1dB:
This presents 20 pulses of 1dB increments. It also counts the patient responses, but this time it is stored in memory as
the test result in percent. This happens when 20 pulses has been presented, or if there was either 0% or 100%
responses to the first 10 pulses.
The patient is allowed to respond within a period of 3 seconds after each pulse. The response lamps will always show
the responses, but they are not counted up if they occur later than 3 seconds after the pulse.
While the test is running, the frequency display is used for pulse counting and the VU display is used for patient
response counting. The channel 2 attenuator display shows the sound level and the pulse increment, when it happens
every 5 seconds.
Using the test:
The test is controlled on the audiometer’s channel 2. When the FUNCTION setting is set to SISI, then the VU will
display changes to show the test results. Also the attenuator to channel 2 is preset to a level 20dB higher than
channel 1. This is just for convenience, as a SISI test is usually performed at 20dB higher level than the patient’s
hearing threshold. The level can be changed freely with the attenuator buttons before the test is started.
After setting the INPUT to TONE and the OUTPUT and FREQUENCY to the desired channel and frequency, the test is
started by pressing the INTERRUPTER. A breef “SISI TEST” is displayed, followed by “5 dB”, to indicate that the 5dB
amplitude mode is running. While the test runs, the ATTENUATOR keys are used to change the amplitude mode. UP
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