论文部分内容阅读
861电台采用主机加耳机话筒组的结构,使用时,头戴耳机进行通信。由于无静噪功能(即不能消除无信号时的噪音),严重影响指挥员的听觉,因此,有必要解决静噪问题。本文介绍一种在不改动电台主机结构和电路的基础上,静噪耳机话筒组的设计。 基本方法:在重新设计的控制盒内,增加固定频率控制信号产生电路、频率/电平转换电路及控制静噪电路。收信机平时处于静噪状态,由静噪转为收话(报)时,需由发信方来启动。即发信方发信前,轻按一下定频控制信号产生电路的揿键开关,使这一固定频率的控制信号经发信机信道发出。收信机将这一信号接收后,经频率/电平转换电路转换成控制电平,触发可控硅导通,使耳机由静噪状态变为受话。通话结束后,收信方轻按串联在可控硅电路中的另一揿键,收信方即恢复到静噪状态。电路具体设计如下:
861 radio host using the headset microphone structure, use, wear headphones to communicate. Squelch is a problem that needs to be addressed due to the absence of squelch (ie, the inability to eliminate noisy signals) that can seriously affect the pilot’s hearing. This article describes a without changing the radio host structure and circuit based on the design of the mute headphone set. The basic method: In the redesigned control box, add a fixed frequency control signal generation circuit, frequency / level conversion circuit and control the squelch circuit. Receivers usually in a mute state, from mute to receive calls (reported), the sender must be started. That is, before the sender letter, tap the key control signal generating circuit 揿 key switch, so that the fixed frequency control signal sent through the transmitter channel. The receiver will receive this signal, the frequency / level conversion circuit into a control level, trigger SCR conduction, the headset from mute state into speech. After the call is over, the addressee pushes another key in tandem circuit in the thyristor circuit to restore the receiver to the mute state. Circuit specific design is as follows: