"Mike Monett" wrote in message
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Check the tank Q. You have the emitter resistor in parallel with the
main tank capacitance. At 3MHz, Xc is 377 ohms. With an emitter
resistor of 1k, the tank Q is just over 2. This is not adequate for
low phase noise.

The series resistance of 1 ohm for the inductor is a bit optimistic.
This would give a Q of 377 for the inductor. Values near this can be
achieved at 3MHz, but it takes special care. A more probable value
is 37, which means increasing the series resistance to 10 ohms.

The capacitance ratio of 5n / 140pf = 35 is quite large. With an
inductor Q of 37, the oscillator may fail to start at higher values
of emitter resistance. So you are constrained to operate at emitter
resistances that give a low tank Q, thus poor phase noise.

Regards,

Mike Monett

you could replace the emitter resistor with an inductor,
say 100uh.
I played around with the jfet ltspice circuit I posted,
it showed less than -40db harmonic,
virtually lost in the digitising noise.

Colin =^.^=