[CQ-Contest] Error detection and correction proposal

AD6E at aol.com AD6E at aol.com
Fri Apr 30 15:38:17 EDT 1999

Kellys' comment gets me thinking a bit.  One of the reasons SS is a favorite 
contest is that is actually requires sending/receiving real data.  I liked it 
better when your birthday was part of the exchange too, but I'm not proposing 
to revive that.

Our hobby is based on providing a public service to the community in the form 
of backup communications which we all take seriously.  CW and even SSB are 
indeed very out of date modes, but they are fun and CW at least can be 
justified because it takes very simple equipment. If we wanted to be 
up-to-date, we'd all be using 512kb/s partial response modems with Viterbi 
coding centered on 14230 :)  using slotted Ahoha packet protocall through 
ARRL hubs.

Ok, I got a little off the subject... sorry.

While sampling great quantities of Tied House beer at the NCCC hospitality 
room in Fresno a couple weeks ago, I joined N6NZ and W6OAT in a discussion of 
error correction in a contest by using a checksum character as part of the 

Going back to the SS exchange, the "check" comes from traffic handling and 
refers to the number of words in the message. This was a crude form of error 
checking and has nothing to do with when you were first licensed. 

Given that most of us use computers to log with anyway, it would be very 
simple to generate a checksum character (one alpha-numeric character) based 
on the transmitted exchange. With serial numbers in the exchange the check 
sum would change for each QSO, modulo 36 (or modulo 1296 if two characters 
are used). Of course we would all have to agree with the formula to generate 
this checksum, and figure out a way for paper loggers to tell us that they 
havn't the foggiest idea of what their checksum should be.

If the transmitted exchange includes this checksum, then when we copy the 
other guys exchange our computer calculates a local checksum value and warns 
us if theres an error in what we copied. This is done in real time so we can 
easily go back to the other guy and ask for fills until the checksum matches 
what was received.

Thus error free contesting. Those who want to save time and ignore the 
checksum can certainly do so... at their peril.

Application of this idea is obvious in SS, but Rusty and Dave thought the 
Sprints might be a better place to start this because of the higher 
probability of both guys in a given QSO using computers.

I don't see all the traffic on this reflector so if this is an old idea I 
appoligize in advance.

73, Al  AD6E
AD6E at aol.com

In a message dated 4/29/99 10:45:35 PM EST, VE4XT writes:

>  After all, if the sole intent of a contest was the pure transmission of 
>  data, would we use a technology that admittedly is as outdated as HF SSB?

CQ-Contest on WWW:        http://www.contesting.com/_cq-contest/
Administrative requests:  cq-contest-REQUEST at contesting.com

More information about the CQ-Contest mailing list