voltage transfer (my 6.002x homework)

[kbcheong]

In this diagram, in order to calculate the voltage transfer ratio, I use the impedance to calculate vo/vin, if the impedance for vo = L + 1/Cjw and for vin = R1, what about R2? is it part of vo or vin?

 

[Harald Kapp]

To calculate Vo make an equivalent circuit consisting of a voltage source Veq and an equivalent impedance Zeq. Veq and Zeq can be computed from Vin, R1, L and C without using R2.
Hint: consider the cases R2=0 Ohm and R2=oo Ohm to arrive at the necessary equations.

Use this equivalent circuit and insert R2. You now have a common voltage divider and you can easily calculate the transfer ratio.

Harald

By the way: You've been given a lot of help in this forum during the last months. It would be nice to get some feedback, too, once your question has been answered.

 

[(*steve*)]

Why don't you help us more by giving us the full question from your homework.

You know, the one that begins:

The inductor and capacitor in the diagram below are part of the output-coupling network of a radio transmitter. The rest of the transmitter (the source of radio-frequency energy) is represented as a Thevenin source, and the antenna load is represented by a resistor.

And why didn't you put this in the homework section?