On Thu, 22 Apr 2004 09:57:32 -0500, Tom McDermott wrote:
>A repeating
>pattern (specifically: RYRYRYRY...) is the worst possible pattern to
>utilize for such test. The pattern should have the most random-like pattern
>of bits. This is because badly-designed modem filters can pass the repeating
>pattern test with good results, yet yield poor copy with more random
>characters.
_________________________________________________________
Could you please explain this further? It would seem to me that a
filter which only processes one bit at a time would have no *knowledge*
of what came before or what follows afterwards, and therefore would not
be capable of recognizing whether a pattern was repeating or not. In
other words, would MARK MARK MARK MARK be processed differently than
MARK SPACE MARK SPACE? Perhaps you are saying that a poorly designed
filter would not handle the transition from MARK to SPACE correctly?
Either way, this could be proven empirically pretty easily I would
think.
--
Bill, W6WRT
QSLs via LoTW
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