[RTTY] Pactor 3 demo

Fri Mar 21 16:52:59 EDT 2014

> So here's your precedent for pushing the wideband digital
> technology, voice+data or just-data to the north side of the
> data/phone spectrum boundary. Let D-STAR do its digital voice + data,
> or for that matter data-only [with the N3BAH device].

This is exactly what I have been saying all along - wide band data
needs to be in the "phone" bands and subject to the same 3/6 KHz
(or 2.5/5 KHz) rules as single sideband and AM/ISB.  The rules are
rather clear that no non-voice emission can be wider than the equivalent 
*communications grade* voice signal - which works out
to be 2.5/2.7/2.8/3.0 KHz for a single channel system (e.g. SSB)
and 5.0/5.5/6.0 for a dual channel (ISB, multiplex, or AM).

> Perhaps, based on D-STAR precedent, we should encourage Pactor to
> join D-STAR in the (previously) phone-only band segments.

It's not just D-Star ... consider STANAG, M110 and other NATO wave-
forms or ALE.  It seems absolutely absurd to require two frequencies
- one for the data/sounding and one for the digital voice - in
different parts of the band based on the "payload" for otherwise
identical emissions.

The *only* concern I have is the one raised by Dr. Flowers - the
"modulation key" should be restricted to a single *published* value
for each protocol.  Similarly *encoding* algorithms (like the D-Star
codec) should be required to be published so the content of the
transmissions can be monitored without the "tax" of purchasing a
specific piece/brand of hardware.

In any case, RTTY/data added to the voice/image allocations as I
proposed in my "late" comments:
    http://apps.fcc.gov/ecfs/document/view?id=7521065473
would address all of these issues except Dr. Flowers' concern for
incidental encryption (and that is an easy change).  The smart
approach is to press each of your Directors to make K1ZZ withdraw
the League's RM-1170 proposal in favor of a bandwidth based solution.

73,

    ... Joe, W4TV

On 3/21/2014 3:09 PM, Kai wrote:
> There is a further "worry" that I have as digital  technology marches
> forward.
> We're 50+ plus years beyond the introduction of simple amateur-RTTY,
> and rules have not kept pace with amateur practice.
>
> Yes, I keep harping on the BW loop-hole that allowed appearance of wide
> band data-only modes like Pactor 3.  The picture is messier, however.
> Icom has established D-STAR technology as a viable alternative to FM
> voice and data at UHF and VHF. Their HF-UHF transceivers, however, are
>   D-STAR capable in all bands even the HF bands. There are D-STAR
> "watering holes" now in the voice sub bands at HF, and there are nets at
> HF using D-STAR.
>
> D-STAR is a complex QAM digital modulation scheme that interleaves digital
> voice with digital data on the same channel. The signal bandwidth is 6 kHz,
> and is well documented (except for a proprietary vocoder).
>
> So, on the one hand, here is precedent for users of a wide band (6 kHz)
> digital technology, which has appeared in the voice sub-bands. It is also
> simultaneously a data (SMS-like) system. Data and DV can appear
> simultaneously,
> or voice-only or data-only [see N3BAH "D-terminal...", Apr QST].
> .
> I'm sure that you will agree with me that even just the data portion has
> no business
> appearing in the CW/data portions of the bands.  I hasten to add that it
> has not
> appeared outside the phone segments ---- but because of its design
> it DOES place a data channel interleaved with the digital voice on the
> same signal -
> and folks are using it in the phone segments at HF.  The phone segments
> are no
> longer "purely" phone, they never were, once "image" was allowed up there.
>
> So here's your precedent for pushing the wideband digital technology,
> voice+data
> or just-data to the north side of the data/phone spectrum boundary. Let
> D-STAR
> do its digital voice + data, or for that matter data-only [with the
> N3BAH device].
>
> Perhaps, based on D-STAR precedent,  we should encourage Pactor  to join
> D-STAR
> in the (previously) phone-only band segments.
>
> -Kai, KE4PT
>
>
>
>
> On 3/21/2014 12:03 PM, Joe Subich, W4TV wrote:
>>
>>> Prior to the start of the demonstration, at the monitoring station,
>>> we observed an existing SSB conversation going on just slightly off
>>> the frequency and a CW station calling CQ on the frequency. After the
>>> demonstration was complete the SSB station was still there but the CW
>>> station was gone.
>>
>> This is a prime example of the asymmetric nature of interference from
>> wide band modes to narrow band modes.  It is *exactly* the reason the
>> FCC has, for approximately 80 years, protected narrow band modes in
>> between 30 and 50% of each HF amateur band from interference by wide
>> band modes.
>>
>> The Commission restated and reaffirmed that policy when ARRL requested
>> that *wide band* image transmissions be included as data.  In WT Order
>> 04-104 (FCC 06-149) in 2006, the Commission clearly rebuked ARRL:
>>
>>> we note that eliminating or relaxing the bandwidth limitation would
>>> de facto eliminate the separation of narrow bandwidth and wide
>>> bandwidth emissions. We believe that separation of emission types by
>>> bandwidth is accepted in the amateur service as a reasonable means to
>>> minimize interference on shared frequencies and bands and, therefore,
>>> we will not replace the 500 Hz bandwidth limitation with a 3 kHz
>>> bandwidth limitation.
>>
>> In footnote 89 of the same order the Commission expanded on the reasons
>> for the separation of wide bandwidth modes from narrow bandwidth modes:
>>
>>> Separation of emission types by bandwidth minimizes or reduces
>>> interference because it protects narrow signals from interference
>>> from wide signals. Amateur licensees have accepted this division of
>>> spectrum as a method for minimizing interference for as long as the
>>> amateur service has been regulated, and no commenter in this
>>> proceeding requests eliminating emission segmentation based on
>>> bandwidth.
>>
>> The entire Report and Order in WT 04-104 (FCC 06-149) is here:
>> http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-06-149A1.pdf
>>
>> Based on the Commission's policy since the 1930's, ARRL *should have*
>> simply requested that RTTY and data be added to the list of wide band
>> emissions permitted with Phone and image, subject to the bandwidth
>> limits in 97.307(f)(2):
>>
>>> (2) No non-phone emission shall exceed the bandwidth of a
>>> communications quality phone emission of the same modulation type.
>>> The total bandwidth of an independent sideband emission (having B as
>>> the first symbol), or a multiplexed image and phone emission, shall
>>> not exceed that of a communications quality A3E emission.
>>
>> Then the "loophole" that K1ZZ and KE4PT are so concerned about (multi-
>> carrier digital systems with symbol rates less than 300 baud) could be
>> precluded in the "narrow band" segments simply by amending 97.307(f)(3)
>> to specifically include a 500 Hz bandwidth limit without precluding
>> any experimentation, development, or deployment of new codes and
>> PACTOR 3/4 would be free to compete with other wideband modes.
>>
>> Note that "regulation by bandwidth" which K1ZZ disingenuously claims
>> would be a new regulatory paradigm has, in the mind of the FCC, been
>> a fact of life for 80 years.
>>
>> 73,
>>
>>    ... Joe, W4TV
>>
>>
>> On 3/21/2014 11:27 AM, Terry wrote:
>>> Yesterday a few of us witnessed a demonstration of Winlink using the
>>> PACTOR
>>> 3 waveform.    A simple one line email was sent from a EOC center in
>>> North
>>> Texas to one of the Winlink stations in Central Texas around 6:00 PM
>>> CST.
>>> The demonstration was monitored at a station in-between.   The
>>> demonstration
>>> was done on 40 meters just above 7.100 MHz.    Prior to the start of the
>>> demonstration, at the monitoring station, we observed an existing SSB
>>> conversation going on just slightly off the frequency and a CW station
>>> calling CQ on the frequency.     After the demonstration was complete
>>> the
>>> SSB station was still there but the CW station was gone.   The
>>> transfer was
>>> not timed but it was quick (probably two minutes) .
>>>
>>>
>>>
>>> So  I want to retract my earlier comments about Winlink being
>>> slow.     The
>>> demonstrated QRMing is a concern.
>>>
>>>
>>>
>>> Thanks,
>>>
>>>
>>>
>>> Terry
>>>
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>> RTTY mailing list
>>> RTTY at contesting.com
>>> http://lists.contesting.com/mailman/listinfo/rtty
>>>
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