hi all - I've been asked to provide a bit of a tutorial on the message buffers to use for this contest. 

TL;DR: Here are the messages to set up for the contest, or at least my idea of what they should be. There are many other ways that are also fine. Bonus content is a blurb on the Baudot code, and an example setup for Writelog. I expect someone can reply with the equivalent for N1MM+.

First off, what I have to say here will be specific to the Roundup but AA5AU has a smashingly detailed writeup that explains the "why" of it all in general:

Also, what follows is not specific to any contest logger so you'll need to look up your syntax - I can help with Writelog and I bet someone else here can cover N1MM+ etc. But there are examples at the end of this.

The following "primary" messages should start with whatever makes your logger send a new line (carriage return (CR) and line feed (LF) characters), and they should end with one space plus whatever is needed to tell your logger to stop transmitting (if any).

(You'll notice that these are pretty similar to what you would do for a CW contest, but the new line or space beginning, and space at the end are very important to keep your messages clear of the noise.)

(new line)RU WK6I WK6I CQ = start with 'RU' to show you are in the contest, and ending with 'CQ' will help the skimmers find you and spot you. 

(new line)(their-call) 599 CA CA = The exchange beginning with the other station's call. You have to send each element at least once. The CA is best to repeat twice, but you can get away with one CA when you are loud or conditions are good, and because of your 6 call. There is never a need to repeat the 599.

(new line)TU WK6I CQ = Acknowledge the received exchange with a cheerful appreciation and make it clear who owns the frequency, and help the skimmers.

Variations... 

- When conditions are good and rates high I'll drop down to one callsign in my CQ: RU WK6I CQ

- In principle that exchange is set up for running but it is also okay for Search&Pounce, and especially if the frequency is crowded the other station will appreciate hearing their call back to confirm you are actually responding to them. But if you want by all means make a S&P version like: 599 CA CA

Below are other good messages to have handy. These are better to start and end with a space - instead of a newline - in case you need to send them more than once.

(space)WK6I = aka your call. You'll know when you need it. ;) I prefer just having the call once so you can decide in the moment how many to send.

(space)(their-call) = Pretty much any other time you need to send their call: 1) If I am running and I am getting a lot of callers, I will add their call on the end of the exchange; the first one may have been obliterated by late callers. 2) When S&P on a very busy frequency, send their call once before sending yours 2 or 3 times.

(space)AGN? = for any general repeat, including a callsign you aren't quite copying. (You could also have QRZ? handy, sometimes DX don't grok the AGN?)

(space)QTH? = repeat state/province. Some will do STATE? but the VEs don't like it. ;) 

(space)NR? = the one other thing you might need a repeat for, DX sends a serial number.

(space)CA = I prefer just having the state once so you can decide in the moment how many to send.

(space)QRL? = Because asking if the frequency is in use is being nice. If you do it and I do it then at least two of us will be doing it.

(space)KB = because why not? :) Or you can do KB WK6I CQ as an alternate to TU.

Also, be sure to have a key defined to start transmitting and type a message, for anything else you may need to send. This is a good to practice when you don't need it because when you do need it you are likely to be busy. 

In summary: The above is how I do it. There are other ways that are just as right. You will certainly see all of them this weekend!

Get to Know Baudot

A RTTY signal uses a 5-bit Baudot code to encode all letters, numbers, punctuation, and control characters. A quick bit of math will reveal that 5 bits is not enough for everything, so special "shift" control characters is defined to switch between letters and figures (including numbers) - commonly referred to as LTRS and FIGS.

In a contest you can fail to correctly decode some characters - this is why we send the important parts twice. However, if you lose a FIGS character then the number you are trying to get is no longer a number. For example, if that VK is trying to send you serial number 25

59925

and you don't get the FIGS, then you'll receive

TOOWT

There is a trick that can help you deal with this without needing a repeat. Just note that the top row of letters are shifted to send the numbers. So the five bit code for 1 is the same as Q after FIGS is sent or received, and W is 2, and so on. Knowing this will save you from many repeats.

Note that most modern modem software implements "unshift on space" (USOS) which means it always assumes LTRS applies after any space sent or received. This is a good thing and can reduce the impact of a lost character. So with USOS that VK is really sending 

FIGS 599 SPACE FIGS 25 

And if you missed the just first FIGS you'd see

TOO 25

This is a good thing.

Some people will use a dash between numbers because going to a space forces an extra FIGS. It's not wrong and not enough benefit to worry about.

I think that's probably more than enough. See you in the WW and Have Fun!

73 jeff wk6i

Appendix - Sample message buffers for Writelog. I'll need someone to chime in on N1MM+

%RRU WK6I WK6I CQ %E

%R%C 599 CA CA %E

%RTU WK6I CQ %E

 WK6I %E

 %C %E

 AGN? %E

 QRZ? %E

 QTH? %E

 NR? %E

 CA %E

 QRL? %E

 KB %E (or %RKB WK6I CQ %E)