Results from eight overnight transmissions of the
3 character message:

 2017-12-10/11  Eb/N0 = -13.1 dB
 2017-12-11/12  Eb/N0 =  -6.3 dB, phase 125.3
 2017-12-12/13  Eb/N0 =  -6.8 dB, phase 143.2
 2017-12-13/14  Eb/N0 = -19.6 dB (stopped 03:40 by safety limit)
 2017-12-14/15  Eb/N0 =  -6.0 dB, phase 68.8
 2017-12-15/16  Eb/N0 = -11.0 dB
 2017-12-16/17  Eb/N0 = -14.6 dB
 2017-12-17/18  Eb/N0 =  -9.9 dB, phase 37.0 (stopped 04:19 by snow)

Stacking

 11/12 + 12/13 gives Eb/N0 = -3.6 dB.
 11/12 + 12/13 + 14/15 gives Eb/N0 = -3.0 dB.
 11/12 + 12/13 + 14/15 + 15/16 gives Eb/N0 = -2.5 dB.
 11/12 + 12/13 + 14/15 + 17/18 gives Eb/N0 = -3.4 dB.

There's some phase changing going on here which is making
stacking not so effective.

--
Paul Nicholson
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