摘要 |
<p>An RF transmitter for being attached to microphone includes a first connecting plug and a second connecting plug which are inserted into a microphone jack and an AV connector of a karaoke device with built-in microphone, respectively. The first connecting plug receives an electric power for driving a microphone of the karaoke device, and the second connecting plug receives an audio signal from the microphone. The power supplied to the first connecting plug is applied to an oscillating circuit provided on a transmitter, and in turn, the oscillating circuit is driven to modulate the audio signal inputted from the second connecting plug at a predetermined frequency. An FM-modulated audio signal is amplified, and then transmitted to an FM receiver from an antenna.</p> |