[RTTY] Hints and tips on how to file comments on RM-11708

[Kok Chen]

Kai wrote:

> The manufacturer claims an occupied BW of 2.2 kHz not 2.4 kHz as I used in my argument before.

Hah, didn't I tell you that SCS claims it is 2K20J2D? :-) :-)  2K20.

You are probably referring to this manuscript perhaps?

http://ecjones.org/PT-III.pdf

Other than Pactor III, there is another number that has to be taken into account so you don't step on the current rules (appears on two separte 97 paragraphs, however, so not as obvious).  And that is:

1000 Hz FSK shift at 300 baud.

Depending on how you implement it, that is in the region of 1200 Hz to 1300 Hz.  So we know that amount of bandwidth is perfectly legit today.   But it has never be reduced to practice, so there might not be legal precedence.

However, 850 Hz shift at 45.45 baud has been permitted since the day FCC allowed amateurs to use FSK instead of OOK.  That is about 1 kHz bandwidth (but with the FSK equipment of those days, probably more like 2 kHz wide :-).

73
Chen, W7AY