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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