i wanna make a VCO working on 900 MHz by using another one working on 100 MHz beside a Harmonic Generators to get the 900 MHz, so my question is how to make a Harmonic Generator? and what considerations should i make in designing it ?
You need a 100MHz signal with very sharp edges to generate harmonics. This can be achieved by using step recovery diodes. **broken link removed**
Another way is to design a multiplier using varactor diodes. You then filter out the final wanted frequency. Look at www.agilent.com and search for frequency multipliers in the application notes. I remember seeing it there.
Thanks Alot E-design;
But I still have a question : How to make the Harmonic Generator pratically(in circuits)? As i know the harmonic generator is Class-C Amplifier, how can i design it for my specifications?