The image reproduced below was sent by W0LMD (in Colorado) to KB4YZ (in Indiana) on 40 meters, with 20% of the outer code symbols being redundant.
As shown by the table of errors corrected in this recording, conditions were good enough for much less redundancy to have been successfully used. Two of the blocks had no errors to be corrected at all, and two more blocks had only a single subcarrier of a single symbol that needed to be corrected. Three blocks had two symbols with errors, and one block had three symbols, each with a single subcarrier in error.
Block inner | outer code | outer | inner code
# code | erasures | code | changes
changes|1st 2nd 3rd | changes | 0 1 2 3 4
---- ------ |--- --- --- | --- | --- --- --- --- ---
0 1 0h 0s 0t 0 || 305 1 0 0 0 +
1 0 0h 0s 0t 0 || 306 0 0 0 0 +
2 3 0h 0s 0t 0 || 304 1 1 0 0 +
3 0 0h 0s 0t 0 || 306 0 0 0 0 +
4 1 0h 0s 0t 0 || 305 1 0 0 0 +
5 3 0h 0s 0t 0 || 304 1 1 0 0 +
6 3 0h 0s 0t 0 || 303 3 0 0 0 +
7 3 0h 0s 0t 0 || 304 1 1 0 0 +
The table headings are:
Block inner | outer code | outer | inner code
# code | erasures | code | changes
changes|1st 2nd 3rd| changes | 0 1 2 3 4
---- ------ |--- --- ---| --- |--- --- --- --- ---
Below is a list of each of the above column headings, from left to right, and an explanation of what is meant by each column heading.
This is an index, starting with 0, used to internally number the outer code blocks.
This is a total of how many of the sub-carriers had their phase changed by the inner decoder, in its attempt to correct as many errors as it could.
An "erasure" means that an error has probably been detected, but not corrected. The sub-headings "1st, 2nd, and 3rd" show how three different categories of erasures, detected by the inner decoder, are to be used by the outer decoder.
All those in the "1st" column are to be used 1st, followed by those in the "2nd" column, followed by those in the "3rd" column. The erasures in the "1st" column result from the received combination of phases being too far away from all code words, even when 4 of the 8 sub-carriers are ignored.
This is a count of the number of symbols corrected by the outer decoder. A negative number means that the outer decoder recognized that it could NOT decode the block correctly.
The five sub-headings, "0, 1, 2, 3, and 4" indicate how many of the 8 sub-carriers were changed by the inner decoder. The numbers in the table are how many of the symbols (in each block) had the respective number of sub-carriers changed by the inner decoder.
Thus, the sub-heading "0" is for the case of error free symbols (0 of the 8 sub-carriers were changed by the inner decoder.)
The image reproduced below was sent by W9NTP (in Indiana), through the satellite FO29, to W8ZCF (in OHIO), with 20% of the outer code symbols being redundant.
The image reproduced below was sent by W8ZCF (in OHIO), through the satellite FO29, to W9NTP (in Indiana), with 20% of the outer code symbols being redundant.
The next two images were received by W8ZCF (in the United States) from transmissions by VK3CQE (in Australia) on 20 meters, just after a series of HDSSTV test transmissions.
The first image below was sent in Scotty 1 mode.
The second image below was sent in Scotty DX mode.
Just prior to the Scotty 1 transmission above, W8ZCF received a HDSSTV transmission from VK3CQE, which was successfully decoded into the image reproduced below. This transmission used 40% redundancy in the outer code, and was also on 20 meters.
The image reproduced below was transfered from VK4CS (in Australia) to W8ZCF (in the United States) over 20 meters, using 40% redundancy in the outer code.
Below is a Robot 36 second image received by W9NTP (in Indiana) from a transmission by W4HTB (in Kentucky) on 75 meters. This transmission took place just after a series of HDSSTV transmissions by W4HTB.
Below is the image resulting from decoding a transmission by W4HTB (in Kentucky) as received by W9NTP (in Indiana) on 75 meters. This transmission used 40% redundancy in the outer code, and took place just before the Robot 36 second image above was received.
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