•
the characters and the inter-character-spaces are then sent to the printer routine
which prints them out on the display
•
One very important addition is an error correction routine which -in the case of a
sequence of dits and dahs that can not be assigned to a character in the look-up-
table- tries out several possibilities to eliminate single dots in order to finally
match the dit/dah sequence to existing characters in the look out table. Also the
error correction tries to correct too short character spaces
•
So, we are finally there: a sequence of characters and spaces which hopefully
matches the transmitted CW message to a certain extent
Please note that still -in 2017!- there is no algorithm which performs better on
decoding of CW signals than the human ear/brain of trained CW experts! Even
highly sophisticated machine learning algorithms do not perform better than
experienced CW operators.
PSK
This is under development. See discussion under
#1002
and add any opinions or useful
links there.
PSK demodulation
works as follows:
•
switch demodulation mode to PSK-U or PSK-L depending on band and/or your
personal preference
•
use a narrow filter that includes 1000Hz center frequency (for example the
500/950Hz filter)
•
coarse tune into a PSK31, PSK63 or PSK125 transmission signal (the center
frequency is 1000Hz, which is indicated by the vertical line inside the filter
passband)
•
press M3, so that orange "PSK" box becomes highlighted
•
adjust PSK mode (31, 63, 125) with encoder 3
•
fine tune with the SNAP button (only works -100Hz around the 1000Hz
center frequency)
•
perform further finetuning with 1Hz steps
•
you should now see the PSK transmission text decoded in the text line
PSK transmission
works as follows: Connect USB keyboard switch to digital mode PSK
and type text. Use F1 and F2 to switch tx/rx. Or long press M1, while in CW mode record
