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Re: [RTTY] Why QR for the section????

To: RTTY Reflector <rtty@contesting.com>
Subject: Re: [RTTY] Why QR for the section????
From: Kok Chen <chen@mac.com>
Date: Sun, 28 Sep 2008 21:08:43 -0700
List-post: <rtty@contesting.com">mailto:rtty@contesting.com>
On Sep 28, 2008, at 8:45 PM, David Wilburn wrote:

> I hit EE3R a couple of times.  They kept sending QR for their section.

Is this right after they sent 599 and a space?  If so, it is possible  
that you have USOS set, and they didn't have it set.

When that happens, that space character will cause your decoder to go  
to LTRS mode.

If he is not running USOS, his state is still in FIGS mode after  
sending the space (the space character is present in both the LTRS and  
FIGS table).

So, when he wants to send you the 1, he simply sends the Baudot 0x17,  
without having to send a FIGS first, after that, he sends a Baudot 0x0a.

On your end, you have shifted gears to the LTRS set (because of  
USOS).  So, when you receive the Baudot 0x17, you print the LTRS  
equivalent, which is a Q.   The Baudot 0x0a is decoded into an R.

So, he sends 14, and you receive QR.

There is no need to panic.  Just look at your keyboard (if you are  
using a regular QWERTY keyboard).  Notice the row of QWERTYUIOP keys  
are under the numerics row 1234567890.

In Baudot, Q and 1 shares a code character, W and 2 share another code  
character, E and 3 shares another code etc.

When a noise pulse takes away FIGS characters, you often see a 599  
turn into a TOO.  73 turns into UE, etc.

The good thing about USOS is that it provides a way to produce a  
cleaner text print -- you won't end up with a page full of numbers,  
when the other end is just sending text.

The bad thing about USOS is that unless everybody uses it, it can  
often cause even more confused print -- especially in a FIGS rich  
environment (e.g., contest exchanges).  USOS is a biased encoding that  
favors the LTRS shift (since SPACE implicitly maps to SPACE+LTRS).

Asking the other end to resend will not help, since precisely the same  
sequence will repeat (Einstein defined as "insanity" as doing  
something repeatedly and expecting different outcomes -- this was  
before he bought into Quantum Mechanics :-).

73
Chen, W7AY



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