Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

FM oscillator

Status
Not open for further replies.

tussi

New Member
Hi. How can I make a stable fm oscillator?
I have built this fm transmitter: **broken link removed** . But the oscillator is not stable... How can I fix this??
 
L1 should be made with large enuf wire that it is self supporting and physically stable, don't wind it on plastic or wood. Use a negative temperature coefficient capacitor for C5. Values from -100PPM to -750PPM are available, you will have to experiment.
 
I have tried that. It won't work.. If I buffer the oscilator, would that help? How can I build it more stable? Can I use crystal or ic for the local oscilator?
 
The buffer not solved the stability problem. Use PLL with XTAL like this cct.
 

Attachments

  • pllfmtx_142.jpg
    pllfmtx_142.jpg
    105.6 KB · Views: 513
Hi. Tanks for replying.
The circuit looks good, but I cant get IC3 and BB105.. What is the value of the crystal?
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top