[hpsdr] Pennylane output power

[george byrkit]

Dear John,

You may well want to hear from Phil or Bill or Scotty on this, but the
ability to reduce power without sacrificing quality, due to using fewer bits
of the DAC to encode the signal, was one of the significant design goals of
PennyLane over Penelope.  So was splitting the output amplifier from 1
section to 2 sections to improve the output as frequency went up.

The software that uses PennyLane is set to use as many of the 16 bits as
possible without overflowing, which causes bad distortion as the digital
value wraps around from full positive to full negative.  The power output
then is used to scale the DAC's output to the desired power range.

My explanation may be over-simplified, but I think I'm saying it right.

Other design goals were the elimination of the toroidal transformers, which
has happened as well.

If you happen to have a Penelope AND a PennyLane, and can put them
side-by-side, you will notice that there is a LOT in common between the two
boards...

73,
George Byrkit, K9TRV
Metis beta tester, KISS hacker


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