Howdy...
Hi, some information from the owners manual:
TECHNICAL INFORMATION
Microphone
(Electret)
Bias required: 8 to 16 VDC through 220 to
2200 ohms
Sensitivity: Varies depending upon bias and
radio AC input impedance. Typical output is
600 mV at 114 dB SPL. To assure proper
modulation of the radio, it is recommended
that an avionics technician adjust its input to
match the output of the microphone.
Microphone
(Dynamic)
Impedance: 5 ohms
Sensitivity: Equivalent to M-87/M-101
Cheers
NZPilot