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Section 1: Coupler Tests of FM Systems
8.
Thread the probe tube through the probe tube adapter so that it extends 3 mm past
the end. Use Fun-Tak to hold the probe tube in place. See Figure 1.4.1B.
9. Insert the adapter and probe tube (attached to the probe microphone) into the HA-2
coupler, and attach to the button earphone, direct audio input hearing aid, or aid
coupled with neck loop or silhouette, as explained in Section 1.1.
10. You are now ready to test the FM system with the signal delivered to the environ-
mental microphone.
Figure 1.4.3B
Leveling the sound field
Figure 1.4.3C
Testing with body-worn receiver