Using Other Microphones - Kenwood TH-78A Instruction Manual

Using Other Microphones

If not using the Kenwood SMC-33 microphone (made for this radio), we recommend using an electret type
microphone. The input impedance is 2K ohms and the DC voltage on the microphone terminal is approximately 4
volts (Max. 3.5mA). Do not use a dynamic microphone.
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