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

[Kai]

Chen
I finally found non-ARRL info about PACTOR-III. The manufacturer claims an 
occupied BW of 2.2 kHz not 2.4 kHz as I used in my argument before. So where I 
used '2.4 kHz'  before I now put '2.2kHz'  - and source the data as the 
manufacturer's tech manual.  In previous emails I was using the 2.2 kHz figure, 
but went to 2.4 erroneously because of the ARRL mistaken claim in the proposal.

My bottom line now reads:
____
I can see a 2.2 kHz BW limit below 28 MHz, and 2.8 kHz above 28 MHz.

If I make comments, they will be to support the ARRL proposal in general, EXCEPT 
to modify the ARRL proposal such that Table (c) make no changes, then in (3) 
change 2.8 to 2.2; do not delete (4) but instead use the language proposed (3) 
with the 2.8 kHz limit.

The net effect of the proposal is most clearly shown in the Table of page 2, the 
"Maximum Symbol Rate" column would be deleted, and in the "Authorized Bandwidth" 
column, the entry for 160-12 m  would be 2.2 kHz (ARRL wants 2.8 kHz), and the 
10 m entry would be 2.8 kHz.

The "if I make comments" is predicated on finding and being able to present 
credible, cite-able evidence that 2800 Hz would cause harm to current users of 
the affected spectra. I emphasize "credible and cite-able" not speculative or 
anecdotal. Chen, I think you might have material which may work. Why is 2800 Hz 
harmful?

Respectfully and 73,
Kai

On 11/24/2013 9:01 PM, Kok Chen wrote:
> On Nov 24, 2013, at 5:02 PM, Joe Subich, W4TV wrote:
>
>> PACTOR III is *NOT* currently permitted under the rules.  Its use has
>> been *overlooked* by enforcement organizations as it *absolutely* can
>> not be justified under the *dual standard* in 97.307(f)(3) which has
>> both 300 baud and 1000 Hz shift limits.
> That is not true Joe... please don't make that mistake in your FCC filing.
>
> At all SL levels, Pactor III's symbol rate is fixed at 100 baud (yes, not even close to 300 baud).  (Don't confuse Symbol Rate (baud rate) with data rate (bit rate)).
>
> Pactor III is not 2 tone FSK, so the FSK shift rule does not even apply (makes no technical sense since there is no frequency shift happening).
>
> Pactor 3 SL1 (the slowest rate) consists of two synchronous PSK signals (not FSK), that are separated by 840 Hz.  840 Hz is the maximum tone separation for Pactor 3 (if you want to apply the term "shift" to the signal).  As more tones are added (SL2, SL3, etc), the tone separations become narrow, and at the narrowest, there are 18 tones, separated by 120 Hz from one another.
>
> Pactor 3 SL1, 2 and 3 uses binary PSK, and Pactor 3 SL4, 5, 6 uses Quadrature PSK.
>
> It is much clearer if you go take a look with a panadapter or a waterfall, or if you can, in I/Q phase space.
>
> Pactor 3 SL1 looks like two broad indistinct tones that are 840 Hz from one another, with a distinctive gap in between them.  It is quite unmistakable once you see it on the waterfall.
>
> 73
> Chen, W7AY
>
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