Hi.
An electret microphone inside a sealed compartment/chamber would need a method to magnetically inject ~2V bias in and deliver its audio out to a preamplifier trough the chamber wall.
A pair of coupled coils can supply AC for the bias power with rectification inside. Another coupled pair of coils could extract the audio out of the container. What to consider to avoid interference from powering and audio coils ? Well separate frequencies ? If power goes in on 1MHz; could a single coil serve as transferring both waveforms bidirectionally trough the chamberwall ?
Filters could manage separating the bands. Sort of RFID, Acting onto the transducer and receiving its data. What else to consider ? It will not be a simple project... Is there an existing gadget using such method that you know of ?
An electret microphone inside a sealed compartment/chamber would need a method to magnetically inject ~2V bias in and deliver its audio out to a preamplifier trough the chamber wall.
A pair of coupled coils can supply AC for the bias power with rectification inside. Another coupled pair of coils could extract the audio out of the container. What to consider to avoid interference from powering and audio coils ? Well separate frequencies ? If power goes in on 1MHz; could a single coil serve as transferring both waveforms bidirectionally trough the chamberwall ?
Filters could manage separating the bands. Sort of RFID, Acting onto the transducer and receiving its data. What else to consider ? It will not be a simple project... Is there an existing gadget using such method that you know of ?