I'm looking for a simple, frequency adjustable, sine wave oscillator. The sine wave needs to be as pure as possible. Frequency range from 100 to 120 MHz. The Dallas DS1085 would be perfect, but it outputs a square wave...

Help please! Thanks

 

Originally posted by sibisties@Jun 21 2006, 06:42 PM
I'm looking for a simple, frequency adjustable, sine wave oscillator. The sine wave needs to be as pure as possible. Frequency range from 100 to 120 MHz. The Dallas DS1085 would be perfect, but it outputs a square wave...

Help please! Thanks

[post=17837]Quoted post[/post]​

What you are asking for is an RF signal generator at a frequency range where careful layout, component selection, complex measurement techniques and instruments, and trial and error are the order of the day.

Try Googling the various oscillator types Hartley, Colpitts, and overtone to see if that leads in a fruitful direction.

 

Might try a modification of the following, but I don't know how "pure" the sine wave will be versus what is needed.

PLL for Microwave Local Oscillators

 

Hi,

You might find that a Colpitts oscillator will do the trick, at least as to easily adjustable. The ARRL site should have oscillator designs for anything from 1 Hz to GHz regions.

Measuring the purity of the sine wave at those freq's is going to be interestinjg.