reilei
Junior Member level 1

why my vco is so poor?
I use traditional Colpitts parallel resonance circuits to build a 2.14GHz vco(spec is 90dBc/Hz@10k,110dBc/Hz@100k,140MHz range) but the phase noise is very poor(83dBc/Hz@10k 104dBc/Hz@100k and tuning range is only 140MHz)however i tuned. here is my sch.How can I improve my phase noise( at least 90dBc/Hz@10k 110dBc/Hz@100k tuning range is at least 140MHz)I've try a lot and never get success......
I use traditional Colpitts parallel resonance circuits to build a 2.14GHz vco(spec is 90dBc/Hz@10k,110dBc/Hz@100k,140MHz range) but the phase noise is very poor(83dBc/Hz@10k 104dBc/Hz@100k and tuning range is only 140MHz)however i tuned. here is my sch.How can I improve my phase noise( at least 90dBc/Hz@10k 110dBc/Hz@100k tuning range is at least 140MHz)I've try a lot and never get success......