Help in designing an S-band VCO

abbas.h said:

thanks for response,

i should use 2SC4320 transistor which it's specifications are mentioned here:
https://alltransistors.com/transistor.php?transistor=16060

VCO Gain and output power and also topology doesn't really matter,
but the phase noise should be minimum and the tuning range should be maximum,

i just need a simple circuit, and if it's possible, the project file for ads simulation,

any help would be appreciated
thanks a lot

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BigBoss said:

Phase Noise should be minimum and Tuning Range would be maximum.!!
They are essentially inverse proportional.While Tuning Range ( Kvco) is increasing, Phase Noise is degradaded, so that the VCO becomes more sensitive to Noise fluctuation at Vtune input.
For simplest circuit, you can address to ADSs Oscillator Design Guide for a starting point.Collector Grounded or Base Grounded Collpits configuration would work.Clapp can be an alternative.
A good Phase Noise, the resonator circuit should have a high Quality factor.Also, varicap diodes must have low series Rs value.
There are many parameters to be considered but I'm not sure that you can do or not..
Oscillator design a pretty sophisticated task..

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vfone said:

**broken link removed**

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