.... Your radio needs an amplifier mic. element to work with the microphone bias circuit. You can use a Tube Pre balanced microphone amplifier ...
The TS-440 was designed for use with dynamic microphones with an impedance range of 500Ω to 50kΩ.
The actual impedance of the mic input is about 10kΩ.
The 150Ω of the Beringer is a litte on the low side, however, correctly wired it shoud work without problems (and w/o pre-amp) on your Kenwood.
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