I need something to give me an AC sinusoidal signal of frequency between 1 KHz and 20 MHz. Is there such a chip that can do this that I could purchase and be able to vary the frequency?

 

Maxim had such a chip. But it has been out of production for many years now. Oscillator chips the analog way have kind of died out. Why do you need this

 

Oh...I found one but I'm not sure how good it is:

Nightfire Colpitts Oscillator

 

The Nightfire oscillator produces ONE frequency. To change the frequency you must change the crystal.

 

Rigol 20Mhz Function Generator

I haven't worked with Rigol equipment, but it will do what you want, though not at a high power.

 

Thanks guys! I was looking for something way smaller than a function generator because I have access to those. It seems like I will test my circuit with a function generator, and with the correct frequency needed, I'll just swap it with the nightfire oscillator and the appropriate crystal.

Is this (nightfire oscillator) the only way you can get an analog AC signal at a predetermined frequency without having to buy a bulky function generator? Are there no variable colpitts oscillators out there?

 

Have you considered using one of the many AD9850 or AD9851 DDS modules available on ebay?

 

Hello,

You could have a look at this kit:
http://www.box73.de/product_info.php?products_id=2266

Bertus

 

Hello,

You could have a look at this kit:
http://www.box73.de/product_info.php?products_id=2266

Bertus

Good or bad, I don't know, but sure it looks nice...!

 

Have you considered using one of the many AD9850 or AD9851 DDS modules available on ebay?

This seems really interesting. So this thing outputs a sine wave at any frequency between 0 and 60 MHz? Wow that's pretty neat if so. How do you vary the frequency of the signal from 0 to 60 MHz?

 

This seems really interesting. So this thing outputs a sine wave at any frequency between 0 and 60 MHz? Wow that's pretty neat if so. How do you vary the frequency of the signal from 0 to 60 MHz?

Direct Digital Synthesis

 

Yeah pretty interesting. I'm probably going to grab the AD9851 which has buttons and a display so it kinda works like a bench signal generator except without that bulky size and price