[GreenKeys] Might be a bad weekend...

[jhhaynes at earthlink.net]

On Sat, 1 Dec 2007, Bob Camp wrote:

> With 425 shift you get away from the problem. You can also tolerate more 
> drift on the link. My guess is that drift / frequency tolerance is the bigger 
> issue for the military.
>
I think you're right, and that also explains why everybody used 850 Hz
shift in the early days.  When you try to copy RTTY on a pre-WWII
Super Pro receiver (or even on a SP-600) you understand the problem.