微波EDA网,见证研发工程师的成长!
首页 > 研发问答 > 微波和射频技术 > 天线设计和射频技术 > How to use 100Mhz oscillator output to get audio sound on FM radio?

How to use 100Mhz oscillator output to get audio sound on FM radio?

时间:04-11 整理:3721RD 点击:
i have a little oscillator that outputs 100 mhz, so how can i do to mix an audio sound to that frequency for listen to it on a simple FM radio ?
thanks

I am afraid that 100MHz oscillator is not suitable for this application ..
What you need is a small FM modulator and here is an example:
http://www.electronics-lab.com/proje...012/index.html
Regards,
IanP

I assume you mean for reception on an FM radio. You need to vary the frequency of the 100 MHz oscillator in proportion to the audio signal. If there is a voltage control for frequency tuning, you can tune the oscillator with that. It is possible to also tune the oscillator (in a much more crude fashion) by AC coupling the audio signal onto the oscillator power supply pin. For instance, put a 47 ohm resistor between the oscillator Vcc pin and the supply, then put a 1 uF series cap between the oscillator Vcc and your audio source.

You may have to vary the audio level to keep it from distorting in the radio. And, I assume that you are not using a crystal 100 MHz oscillator, which will not tune enough no matter what you do to it.

thanks guys for help, the problem is that is a crystal 100 Mhz oscillator so as a solution i will take a VCO from an old VHF VCR/TV tuner and i will inject audio signal to the VT pin

You could try an armstrong modulator with the crystal:

http://www.see.ed.ac.uk/~gjrp/EE3/Co...e10/sld006.htm

Copyright © 2017-2020 微波EDA网 版权所有

网站地图

Top