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Old 25th March 2000 | 05:05
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Wide Body
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Dynamic (Moving coil mics generally work on anything) they don't need a DC bias voltage on the mic line to generate an o/p like the electret, and carbon types. It's just a little coil rattling around near a magnet.
On some of the smaller light a/c intercomms, if you mix different types of mic havoc will prevail. These units generally can't cope with different impeadance loading like the big interphone systems.
A good test for a dynamic mic is a continuity test. Around 150 ohms is good I think ??? However, the biggest problem with headset mics is the copious amount of aircrew dribble that makes them damp and un-intelligable. "The mic that is!"
Hope this helps.