spice has the curves built into it so you can display them and analyze the circuit. Common emitter is easiest so i started with it.
The common base works too!
here we have Ic vs Vbe. If R=E/I and Ic=Ie you could pick a point on the curve representing your operating point divide Vbe by Ic and determine your transistor input resistance at that point.
Now the problem is I am using a 2 volt supply and 100 ohm load. It will be different with a 12 volt supply and 10K load. So the circuit needs to be examined as you desire to build it.
One other thing to consider before closing the blog for the day. How do you handle a transformer?
I did a post a year ago on mutual inductance you might do well to look at it. What we are being told here is that the mutual inductance will cause our transformer primary to be loaded as the secondary is being loaded. In a power transformer we make the primary inductance high so we can load the secondary, draw power from the primary, and still not short out the primary. In the case of a tuned circuit the reflected change can cause the tank to detune as it loads. Some food for thought.
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