Hands-free telephone having a handset volume attenuator for controlling speaker volume in a hands-free adaptor

摘要: A hands-free telephone for use on a vehicle includes handset incorporating radio section therein and adapter unit therein. To prevent howling, the two variable attenuators, or variolossers, each changing level of respective ones receive transmit signal to be applied speaker section, respectively, so as maintain levels in predetermined relation. The also resistor which may adjust volume voice delivered through an earpiece within adjusts speaker. level-adjusted is controlled by third attenuator simultaneously with above-mentioned attenuators.