Chen,
> 2) if you elect to operate below 14.095, your signal need to occupy
> no more than 500 Hz.
Again, this shows that the Commission *intended* that normal digital
bandwidth be 500 Hz or less. The *whole reason* for a 500 Hz limit on
automatic operations outside the "automatic control subbands" was to
keep those bandwidths consistent with "traditional radioteleprinter
bandwidths" - or what the 'rest of us' were using.
If you want to look at it another way, I would not be so upset if ARRL
were proposing a 2300 Hz limit for the PACTOR systems in the automatic
control ghettos. Let the wide signals interfere with other wide signals
and leave the rest of the band alone.
Of course, the logical solution is to allow "RTTY, data" modes anywhere
and restrict the 2300 or 2800 Hz modes/protocols to those frequencies
where 2800 Hz modes are already permitted. Such a change would allow
amateurs to use other publicly documented 2800 Hz protocols such as
STANAG and M110 for digital voice.
73,
... Joe, W4TV
On 11/24/2013 8:42 PM, Kok Chen wrote:
On Nov 24, 2013, at 4:49 PM, Joe Subich, W4TV wrote:
The problem is that this is entirely about 2.8 KHz - not automatic
operation *or* the operations of the Winlink RMS network using *either*
PACTOR III/IV or WINMOR 1500 (all of which are not permitted by *any*
station under automatic control).
Joe,
The gist is this (I am going to use 20m as an example).
97.221 says that if you are an automatic station you must comply with one of
the following:
1) if you want to use general RTTY rules (like 97.307(f)(3)), you need to stay
above 14.095 and thus away from the keyboard people, or
2) if you elect to operate below 14.095, your signal need to occupy no more
than 500 Hz.
So, lets say the FCC approves the ARRL petition, but the the FCC keeps '221
remain the way it is (no reason not to think it will not remain, since ARRL is
not asking to change '221 this time after being bitten by RM-11306), then (I
think Kai has already mentioned this) the wideband stuff will still need to
stay above 14.095.
The 500 Hz stuff can still come down below 14.095, but they are already allowed to do so
today, and you do see them, but they are more benign than the wide stuff. (I said
"more" benign, not totally benign, but neither is a steam RTTY signal that sits
on top of a PSK31 or a CW signal.)
So, as long as the FCC keeps the 2.8 kHz stuff above 14.095, the only time the
2.8 kHz affects you is if you operate above 14.095 -- and today, there are
already defacto legal stations that are about 2.3 kHz wide up there.
The only time we get no protection is when automatic stations declare themselves to be
"controlled" because some client is doing the control. If they are making that
claim today, they are already effectively claiming they can use 2.3 kHz on any digital
frequency under current rules. The rules that ARRL propose simply changes the 2.3 kHz to
2.8 kHz.
I agree that 2.8 kHz is absolutely uncalled for, but when it comes to automatic
stations, it is not the difference between 500 Hz and 2.8 kHz worth of QRM, but
the difference is between 2.3 kHz and 2.8 kHz.
Remember RM-11306? That one was about '221 and ARRL withdrew the petition, which means,
as Kai already mentioned, that protective law is still in the books. This new petition
won't change that. We are just as protected (or just as unprotected) from wide
automatic signals as we were before. It is just that ARRL wants to change the meaning of
"wide" to be 2.8 kHz.
2.3 kHz is the defacto definition of "wide" today. That horse left the barn a
long time ago when Pactor 3 SL6 was allowed to be used.
Lets say the FCC strikes out the 2.8 kHz that the ARRL proposes, then we are
down to arguing whether 2.3 kHz (Pactor 3 SL6) is the current widest legal mode.
Like Kai, I also think 2.3 kHz is still uncalled for.
So, think of here is an *opportunity* to actually get the FCC to definitively
change that 2.8 kHz number instead to around 1 kHz (thus allow Pactor 3 SL1 to
remain legal) or 1.5 kHz (allowing Pactor 3 SL2 to remain legal). Pactor 3
modem owners won't have to throw their expensive modems away.
Remember that if '221 is binding, an automatic station still cannot use 1 kHz
or 1.5 kHz wide RTTY below 14.095 (they have to stay at 500 Hz). But '221 is a
different war, which we fought once, and heavens know how many more times in my
lifetime.
BTW, for reference, the existing rules allow 1 kHz shifts for two tone FSK,
which means it already allows 1.3 kHz or thereabouts today (within 10% or 20%
of that back of the envelope number anyway, depending if you apply waveshaping).
73
Chen, W7AY
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