On Mon, 28 Feb 2005 09:55:34 -0600, (Richard
Harrison) wrote:

From the specifications page also, the power reguirement is TX: 18A
13.8V DC. It`s a linear amplifier. Only 40% efficiency. The designer
probably was more interested in low harmonics than efficiency. The final
by itself only takes part of the 18A ao its efficiency is more than 40%.

Hi Richard,

My point exactly. However, how much more than 40% and how much of
that 18A (248W) is not devoted to the finals? Your "typical" rig
would most like be composed of a three stage design with 5W/20W/100W
kind of progression - very common.

The manufacturer of your finals transistors would be quick to spec
them with a ballpark of 45% efficiency (Class AB, in a CW application)
in the best of circumstances for full power.

Perhaps someone else has better Pout/Pin figures for a commonly
available, retail Amateur 100W multi-mode HF rig? Say like 13.8V @
10A for 100W CW?

Again, appeals to deities are always amusing (say what you pray), but
we are missing the photon (sic) explanation (see what you mean) to
completely round this out.

73's
Richard Clark, KB7QHC