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Re: Topband: The use of digital modes on 160 metres

To: "N1BUG" <paul@n1bug.com>, "Topband" <topband@contesting.com>
Subject: Re: Topband: The use of digital modes on 160 metres
From: "Tom W8JI" <w8ji@w8ji.com>
Reply-to: Tom W8JI <w8ji@w8ji.com>
Date: Wed, 19 Sep 2012 10:58:32 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
For the record, I have tried JT65 and other digital modes. I'm not opposed to them, but they are not for me. To each their own, of course, but I would rather watch paint dry than work digital modes. For me it takes the fun and sense of personal achievement out of operating.

It appears to me, if SM2CEW is correct, these are not QSO's at all.

"As we see, in JT65 things are different. The software has significant limitations because the Deep Search module can never decode unknown callsigns or locators. Everything must be known in advance and presented to the CPU. The Deep Search decoder is looking for fragments of the 72 bit long message that the other station is transmitting to compare with the known data already present on the computer. When there is a probability of a match to these received fragments, the calls and a locator is printed in full on the computer screen. During this Deep Search process, the computer may not even have copied half of one callsign to perform the guessing. Two complete calls are at least 56 bits long, but in Deep Search 14 bits or less are required to produce full calls on the screen. This means that 25% or less of the original message is actually required to be received via the radio. The operator is unaware of
this and is lead to believe that all information has been recieved."

They apparently do give users the perception of being a QSO. I wonder why the ARRL even counts them at all?

73 Tom
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