Thomas Magma wrote:


I've often questioned why manufactures put small signal parameters on their
datasheets? Makes no sense to me.

They might be of some use for specific cases. For example, if the PA is class
A, is used well backed off because of high PEP-to-avg ratios of the signal, and
you've managed to get the output load dialed in, s-params can be useful for a
first cut at the amplifier *input* match. I've always still had to do some
tweeking though. Also, with some work and considering the load-line match, they
can give you an idea of what gain can be accomplished. This might already be in
the data sheet though, as you mention.

Even if they do publish some large signal
parameters it is unlikely to be the exact same mode of operation that you
need for your project.

One of the large signal parameters I like best is how much power the device can
dissipate. ;-) Voltage breakdowns and Imax are nice too. ;-) ;-)