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I'm still trying out this oscillator as a part of a PLL FM transmitter.
The last version I posted had some high frequency parasitic oscillations, which I finally figured out where they come from. They were coming from an undamped LC tank that was formed between the 47pF caps at the base of the transistors, the 33nH inductors, through the ground connection and the voltage source and back to the upper end of the 47pF capacitor through the 1uH inductor. Last version used a lot less inductance than 1uH, which didn't have enough reactance to dampen the LC circuit, so a secondary resonance was formed, especially during power up.
This version uses a 1uH inductor for higher suppression and the 5ohm resistance in the LC circuit is formed by the Q factor of the capacitors in the tank circuit. The 50pF cap should be substituted by a few capacitors and a calculated varicap capacitance that would sweep the whole 87-108MHz range. An optional modification would be another varicap circuit for the audio modulation, biased at a steady voltage.
This is somewhat of a final version that I've established for the oscillator-amplifier stage, so next step would be to design a PCB design.
The output filters were designed to deliver the following watts at the whole range.
87MHz - 5.6W
97MHz - 6W
108MHz - 5.6W
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