Automated Test Sequences 107
4.3.4 Running the JIS Test
1. Make sure the sound chamber is leveled. Follow the instructions found in
Section 3.3, if needed.
2. Push the [START/STOP] key.
3. The FP35 will pause during the measurement process in order to let you
adjust the gain of the hearing aid to the reference test position.
a. Lift the sound chamber lid and adjust the gain control of the aid until the
MEASURED gain matches TARGET gain.
b. Close the sound chamber lid when finished.
c. The MEASURED gain should be within 1 dB of the TARGET gain.
4. Push [START/STOP] to complete the test.
5. Press [NEXT] to view the I/O Screen.
6. Press [PRINT] for a hard copy of the results.
4.3.5 Defining the Menu Items
There are two menus for the IEC Screen. The first contains the most basic items;
things you may want to change frequently. The Advanced Menu contains more
advanced features that most users probably don’t need to worry about.
Main JIS Menu
Open the main JIS menu by pressing [MENU] from the JIS Screen.
COUPLER TYPE—Type of coupler used for the test sequence. Choose between 2
cc, MZ, and CIC.
EQ INPUT NOISE—The type of equivalent input noise measurement (EIN)
made with the JIS test. NORMAL sets the EIN to use the entire 200 Hz—8000
Hz frequency band. A selection of 5KHz sets the frequency band to 200 Hz—
5000 Hz (recommended), and a selection of OFF skips the EIN entirely.
NOISE RED— The amount of noise reduction used for the pure-tone measure-
ments. See Section 2.5.1.3.
REF MIC— The status of the reference microphone.
Advanced Menu
Reach the following menu choices by pressing [NEXT] while the JIS Menu is
open.
HDIST 12DB—Status of the harmonic distortion rule. The ANSI standard states
that when measuring harmonic distortion, if the amplitude of the response
curve at second harmonic of the distortion frequency is 12 dB greater than the
response curve at the distortion frequency, the harmonic distortion measure-
