26
Testing FM Systems with FONIX 6500-CX Analyzers
9.
Securely attach the assembly to the floor stand using Fun-Tak. The body of the hear-
ing aid should be vertical with the hearing aid microphone pointed towards the
sound field speaker. See Figure 1.4.1D.
Figure 1.4.1.D
Setup for testing a hearing aid in the sound field using a coupler
10. You are now ready to test the hearing aid.
1.4.2 FM System Setup
Since the tests of the FM transmitter/receiver in this chapter always follow the tests of the
hearing aid, it is assumed in this setup that you have already entered Real Ear Mode and
leveled the sound field speaker. If you are testing out of order, follow the instructions found
in Section 1.4.1, Steps 1-4, to level the sound field before testing.
1. Place the FM transmitting microphone on the floor stand six inches (15 cm) from the
sound field speaker. Keep all sound-entry ports clear of the platform. Place the
transmitter and its cord behind the transmitting microphone.
2. Thread a probe tube through the black probe tube adapter with the tube first enter-
ing the ridged end of the adapter. The tube should extend 1-2 mm past the other
end of the adapter. Use Fun-Tak to secure the probe tube to the adapter. See Figure
1.4.1B.
3.
Insert the adapter into the HA-2 coupler, and attach the probe tube to the probe
microphone. See Figure 1.4.1C.
4.
Attach the FM receiver to the HA-2 coupler as described in Section 1.1.1.