4 basic measurements – Frye FONIX 7000 User Manual

Page 76

Advertising
background image

68

FONIX 7000 Hearing Aid Analyzer

Additional Notes for Testing Wireless Instruments

1. There must not be any metal objects between the transmitter and the receiv-

er sides.

2. The two sides must be directly parallel as illustrated (See Figure 3.3.7).
3. The distance between the two sides should be as specified by the manufac-

turer.

THE GAIN OF THE AID INCREASES AS THE TRANSMITTER AND
RECEIVER MOVE CLOSER TO EACH OTHER. EVENTUALLY, THE
RECEIVER WILL OVERLOAD.

4. No other wireless CROS/BICROS/MultiCROS transmitters are to be turned

on near the test box.

5. Calculators should be kept at least a foot (300 mm) from the test box.

3.3.8 Wire-Type CROS and BICROS aids

CROS
CROS aids are similar to ordinary hearing aids, except that the microphone
and amplifier are separate units connected by a wire. Both units may be placed
inside the test chamber during testing.

1. Place the orifice of the microphone unit at the reference position in the test

chamber.

2. Connect the amplifier unit to the appropriate 2-cc coupler. (See earlier sec-

tions for details.)

3. Place the coupler with the amplifier unit at the left side of the test area.
4. Test as desired.

BICROS
Test wire-type BICROS aids just as you would wireless BICROS aids, except
instead of separating the two units and keeping them parallel, place both units
as close as possible to one another with the microphone openings as close as
possible to the reference circle. (Otherwise, follow the steps given in Section
3.3.7 for BICROS aids.)

3.4 Basic Measurements

In the Coupler screen of the 7000 analyzer, you can perform the following mea-
surements: response curves, single-frequency measurements, three-frequency
averages, harmonic distortion, and intermodulation distortion.

Advertising