On Sat, 24 Feb 2007 22:22:56 -0800, Frank Gilliland
wrote:

+++This method has been used in the real world for many years, and it is still
+++being used. Better ways?
+++
+++
+++Several.
+++
+++Long story short, the power-to-voltage ratio of a signal is always
+++higher than the power-to-voltage ratio of noise. Most RF front ends
+++are voltage amps. But a -power- amp on the left can dig the signal out
+++of the noise on the order of 2-4dB, sometimes more. I like using a
+++common-base for the 1st RF, but you can re-bias a common emitter and
+++make pretty good improvements. And, as I stated before, a low input
+++impedance will reduce or eliminate the impedance transformation prior
+++to amplification.
************

That is true in most cases. Most of my RF work in the front end dealt
around using small loop antenna( less than 1/8 wave) for paging
recievers and those puppies have very low radiation resistance. You
need some impedance transformation even if you do use common base.

james