Cheng Fei Phung,
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I apologize for not replying sooner.? I was taking a look at your original oscillator circuit (with the schematic borrowed from a paper at the ieeexplore.ieee.org website).? I do not believe that schematic is workable as an oscillator, when using the transistor models and sizes that you have provided.? I think the oscillator transistor lacks sufficient gain.? Also, some transistors seem to be biased incorrectly as they do not behave according to your annotations.? I was generating curves in LTspice to illustrate.? But alas, life got in the way for me and I was delayed.
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Have not yet seen your latest version.
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Andy
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