工业控制 | 能源技术 | 汽车电子 | 通信网络 | 安防监控 | 智能电网 | 移动手持 | 无线技术 | 家用电器 | 数字广播 | 消费电子 | 应用软件 | 其他方案

电路设计->国外电路图->国外电路图(一)->Coilless FM transmitter !

Coilless FM transmitter !

发布人:dolphin 时间:2009-08-25 收藏

The RF oscillator using the inverter N2 and 10.7Mhz ceramic filter is driving the parallel combination of N4 to N6 through N3.Since these inverters are in parallel the output impedance will be low so that it can directly drive an aerial of 1/4th wavelength. Since the output of N4-N6 is square wave there will be a lot of harmonics in it. The 9th harmonics of 10.7Mhz (96.3Mhz) will hence be at the center of the FM band .
N1 is working as an audio amplifier. The audio signals from the microphone are amplified and fed to the varycap diode. The signal varies the capacitance of the varycap and hence varies the oscillator frequency which produce Frequency Modulation.


关键词: Coilless transmitter

评论

技术专区

站长统计
×

Digikey let's do
· 2025年第1期限时报名开启,5月8日截止
· Digikey助力,提供一站式免费器件支持
· 跟大佬一起 【DIY 功率监测与控制系统】