Telex Airman 850, Руководство по обслуживанию клиента

Страница: 24 / 34

24 en | Maintenance Airman 850
09-2021 | V07 | F.01U.264.819
Customer maintenance manual
Bosch Security Systems LLC
Frequency response: Must meet standards outlined in Receiver
frequency response table in
Specifications,
page 29.
To measure the speaker, do the following:
1.
Using a B&K type 4153 with 6cc coupler or equivalent, place the headset speaker on an
artificial ear, fitted with the appropriate coupler.
1. Supply the headset with a 1mW, 1KHz signal to appropriate connector. See Wiring
diagrams, page 16.
2. Measure acoustic output of headset using an audio analyzer.
Sensitivity should be 90dB SPL ±5dB re. 1mW at 1kHz, headset in low volume setting.
3. Measure and record the acoustic output over the frequency range of 350 Hz to 3 KHz.
The resultant curve should fit the limits as defined in Receiver frequency response table
in
Specifications, page 29.
4. Repeat steps 1 through 4 with the second speaker, if applicable.
5. Measure current of 12V Power Supply.
The current should be 4 mA ±1 mA with 1 mW applied to the speaker and ANR turned on.
The current should be less than 1 mA without 1 mW applied to the speaker and ANR turned
off.
i
Notice!
If the specifications are not met in either power on or power off mode, printed circuit board
failure should be suspected, see
Troubleshooting chart, page 28.
6.4 ANR validation and adjustment
6.4.1 Active noise reduction (ANR versions only)
i
Notice!
Minimum attenuation requirement are not requirements of FAA TSO.