On 4/26/2011 7:52 PM, Richard Clark wrote:
On Tue, 26 Apr 2011 15:27:28 -0700, Jim
wrote:

(If I had a very efficient op amp, I could simulate any arbitrary output
impedance, without dissipating any power in the source)

I can see why this is parenthetical, because it covers a lot of sins
of omission.

yep.. not possible to build such a thing, anymore than one can build a
zero ohm output impedance RF source with any signficant power.
Suggested more as an example that the power dissipation in the source
doesn't necessarily correlate with match, load Z, or anything else in
general.

(You can get pretty darn close at powers less than a watt and HF, though..)

OP AMPs are a constant of my admiration in the possibilities offered.
That and the signal processing you suggest (plus digital oscillators)
"could" change the playing field - if conventional design weren't so
universally fallen back upon.

73's
Richard Clark, KB7QHC

I wonder if this should be applied to these sorts of projects -

https://www.kb9yig.com/

I have a 1 watt kit that I haven't put together yet. Several others in
our club have and they love them. Especially nice for CW.

tom
K0TAR