| 摘要 |
<p>The telephone adapter for hands-free telephony functions with a telephone handset. A transmit signal path comprises in series, a microphone, amplifier, disabling circuit and a transducer. A receiver signal path which amplifies sound energy from the earpiece, has in series, a coupler, amplifier, disabling circuit and speaker. ]A bias circuit maintains the transmit path in an active state when no signals are present. The circuit paths can be interrupted in a complementary manner. The transmit path may include a re-entrant, exponential horn.</p> |
