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Thanks MRAM1500 for the link to the BCB repeater article. This is a class A amplifier so the efficiency will be at best 50%. Since efficiency depends on several factors such as the load impedance I simulated the circuit to gain an estimate of the efficiency.
I used a load of 30 ohms in series with 30 pF to simulate a 3 meter antenna system and measured the power delivered to the 30 ohm resistance.
A 1600 kHz sine input was used and the amplitude was adjusted to give a collector voltage swing of half VCC to allow for increases with modulation without saturation. The tank circuit was tuned to resonance.
The simulation gave an input power of 73 mW and and output power of 236 microwatts for an efficiency of 0.32%.
If anyone is considering building this circuit these data could be helpful.