Inside Microphone R74 , function test

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With BOSE sound, and Inside Microphone R74 is installed to determine interior noise (AudioPilot). This is switched directly with the Amplifier R12. If interior noise increases, the Amplifer R12 (AudioPilot) automatically increases volume according to a predetermined pattern.

After switching on the Radio R , the Amplifier R12 determines the gauge of the Inside Microphone R74 voltage supply. If the result is OK, there is no reaction.

In contrast, if no Inside Microphone R74 is installed, three short tones sound one after another.

In case of short circuit, three individual tones are heard.

Function test

Switch the Radio R on and set it to a station (pop music, if possible).
Set the volume to approx. "20".
Now lightly tap on the Inside Microphone R74 ( Front Interior Light W1 ) several times.

The volume of the station selected on the Radio R must increase noticeably during the tapping. The procedure is done slowly.

Stop tapping.

The volume of the station selected on the Radio R must decrease noticeably.