Miller negative resistance Oscillator

@7/23,  2015

even though i build several times the miller style oscillator, but i always wonder how it works, even in a very basic level.

<< Practical Oscillator Handbook>> by Irving M. Gottlieb introduce the miller:

In the tuned-output/tuned-input oscillator, the transistor exhibits a 'Miller' effect;  that is, its input acts as a negative resistance

when the output tank is tuned to appear inductive at the parallel-resonant frequency of the emitter-base tank (lower frequency

than base tank). 

* A, radio frequency choke in bias circuit makes for easier starting. reduce bias shunting effect.

* B, C, D, E, Resistors(10-20R) and~or ferrite beads discouraged high frequency parasitics.

* F Tapped tank inductor can optimize impedance match to transistor.

* G, Collector radio frequency choke should be a different value from base-circuit choke A.

* H, I, J, Decoupling network discourages low frequency parasites. 

* K, Faraday shield helps isolate oscillator from load

At higher power levels the collector circuit of the transistor tends to load down the parallel-tuned tank, A tap F, rescu this from BJT.

Miller type oscillator tend to output much power. 10-20mW typically.  one can say this is a Colpitts type oscillator while the C3 is omit(except 1Mhz or 3Mhz).