Frye FONIX 7000 - Manual (Page 107)

Automated Test Sequences
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It then continues through a complete cycle and terminates when it reaches the
baseline again. This signal, although consisting of only a single pulse, contains
very few frequencies above 1 kHz and is one millisecond wide at its base.
The data collected from this measurement is displayed in a graphical format 20
milliseconds wide. The system delay and the digital processing delay are noted
for reference on the phase graph in the form of vertical lines.
4.1.3 Procedure
1. Press [F8] in the Opening screen to enter the Enhanced DSP screen.
2. Set up the hearing aid for testing in the sound chamber. See Section 3.3.
Make sure the sound chamber is leveled.
3. Use [F1] to select the desired ear.
Figure 4.1.3—Enhanced DSP measurement results
4. Press [START] to perform the delay and phase tests for that hearing aid. If
the left ear was designated in Step 4, the results will be shown in the upper
two graphs. Otherwise, they will be shown in the lower two graphs.
5. Set up a second hearing aid in the sound chamber, if desired, and use [F1]
to select the other ear. Press [START] to perform the measurements on this
second aid. This will allow you to compare the results of the two hearing
aids. See Figure 4.1.3.