oscillator with fet

can u made lower freq oscillator and than take the x harmonic ?

The power of harmonic is not enough. I need fundamental signal. :? :? :?

if the power of the harmonic is not enough u can put an amplifier in big satoration and then the harmonics will be alot biger (even like the fundamental).
alot of system do it at this way.
the only one resuen to do dircet osi at this freq is the noise (20log (N))

i think push push oscillator is good solustion for your project.
you can see here,
http://www.elektroda.pl/eboard/viewt...ight=push+push

Hi wu_qiusheng

I also have built several 24GHz oscillators using the NE3210S01. You can use it with a DRO (recommended) or even with lumped elements. What you have to do is to match the gate to 50Ohm. Otherwise you won't have enough gain.
My oscis deliver about 0dBm at 24.125GHz.

Bye

Hi, mr_GHz
I have no DR, so can you tell me how to design by using lumped element.
I change the length of stub in Gate to tune the frequency. But I only got up to 22 GHz and it did not oscillate with shorter stub. Could you help me ?
Please. :) :) :)

Hi wu_qiusheng

You can try parallel feedback. Can you give me a little bit more information what you need (output power, phase noise, application)? You can PM me your current 'layout'. So we surely will find a solution.

Bye

Hello, Mr-ghz, what kind of substrate you employed?

u could follow some books

Mr chinaing, for example.....?

Hi microstrip_line

I use two different substrates: RF35 from Taconic or (much cheaper, usable for oscis but not for antennas or LNAs) LD-621 from PolyClad.

Bye

Sorry, Mr Ghz, I want to know the Er and thickness ?

Hi microstrip_line

When using the above material, er is about 3.2 at 24GHz. I use a material with 0.254mm thickness. I build a 4-layer pcb, so the total thickness is about 1mm which also has good mechanical stability.

Bye

Then, any resolution on just one layer PCB ?

Hi,

For just one layer PCB, it could also oscillate at 24Ghz having a power output of 0dBm.

Mr. yuppi77
Could you give me the layout of your solusion?