Coupler Measurements
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2. Press F1 to enter the General Setup Menu.
3. Select SOURCE with the AMPLITUDE and FREQUENCY knobs.
4. Press START/STOP to select TONE.
5. Press F1 to return to the Main Coupler Screen.
6. Open the sound chamber and listen to the signal. You will hear a continuous pure-tone sig-
nal. Close the sound chamber.
7. Look at the lower right side of the screen. You will see a box listing the SOURCE, FREQ, and
MIC GAIN (or MIC SPL) of the signal.
8. Adjust the amplitude and frequency of the signal using the AMPLITUDE and FREQUENCY
knobs.
9. Watch the MIC GAIN (or MIC SPL) in the lower right side of the screen change as you adjust
the amplitude and frequency of the signal.
3.4.5 Taking a three frequency average
To take the three frequency average of a hearing aid, you use the AVG feature.
1. Press F1 to enter the General Setup Menu.
2. Select TONE for the SOURCE type, if necessary. If you don’t have the Composite signal on
your analyzer, you won’t see a selection for SOURCE type.
3. Use the FREQUENCY and AMPLITUDE knobs to select MAIN F2 or MAIN F3.
4. Press START/STOP repeatedly until you select AVG.
5. Use the FREQUENCY and AMPLITUDE knobs to select AVG FREQS under PURE-TONE
SETTINGS.
6. Press START/STOP to toggle the desired three frequency average, represented by the highest
of the frequencies. See Section 2.4.1 for a list of those frequencies.
7. Press F1 to return to the Main Coupler Screen.
8. Look at the lower right side of the screen. You will see a box listing the SOURCE, FREQ, and
MIC GAIN (or MIC SPL) of the signal. FREQ will be changing rapidly as the analyzer switches
between the three frequencies.
9. Adjust the amplitude of the signal using the AMPLITUDE knob. Watch the MIC GAIN (or MIC
SPL) in the lower right side of the screen change as you adjust the knob.
3.4.6 Viewing harmonic distortion
1. Press F1 to enter the General Setup Menu.
2. Select TONE for the SOURCE type, if necessary. If you don’t have the Composite signal on
your analyzer, you won’t see a selection for SOURCE type.