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Section 1: Coupler Tests of FM Systems
1.3.9 Test environmental mic response with high-level input — EEF90
1. Set up the environmental microphone for testing as described in Section 1.1.4. Set
the FM receiver to FM+ENV.
2. Press [START/STOP] to run a pure-tone measurement at 90 dB SPL.
3. This measurement will be referred to as EEF90 or the Electroacoustic FM and
Environmental Response with 90 dB SPL input to the environmental microphone.
4. To view both curves on the same screen requires the Multi-Curve Option:
a. Press
[MULTI].
b. Highlight
MULTIPLE
CURVES.
c. Press
[START].
d. EEF90 (CRV 1) should be displayed in the first slot, and EFE90 (CRV 2) should
be displayed in the second slot.
e. Press
[
∨
] to select the third slot.
f. If necessary, press [<, >] to select CRV 3 for the third slot. This is the EHA90
measurement.
5. Compare EEF90 (CRV 1) to EFE90 (CRV 2) and EHA90 (CRV 3). All three curves
should match. See Figure 1.3.9.
Figure 1.3.9
Comparison of EHA90, EFM90, and EFF90, the environmental
microphone response at 90 dB SPL
