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VE2HAR > MT63     10.03.05 18:46l 229 Lines 6663 Bytes #-7496 (0) @ WW
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Subj: RE: [MT63] 20 kHz wide Digital Proposal (Was: ARRL MUST GET
Path: DB0FHN<DB0MRW<OK0PKL<OK0PCC<OK0PAD<OK0PPL<DB0RES<ON0AR<VA2HAR<VE2HAR
Sent: 050310/1621z @:VE2HAR.#MTL.QC.CAN.NOAM Laval #:41098 $:25181sentto

Hi Rick,

Quoting Rick Williams <mrfarm@mwt.net>:
> Something to consider:
> 
> In the last week or so, another station and I did some NVIS testing in the
> evening on 80 meters. We were using Olivia and then went to MFSK16 and no
> problem. We switched to MT-63 and the signal was light but you could hear
> it, certainly enough for a CW contact. But no MT-63 signals got through.
> Went back to MFSK16 and no problem.

Ok...well I'm not sure why you didn't copy the MT63 signal...but Olivia should
be more robust that MT63 and MFSK-16 more robust than Olivia.  The difference
between MFSK16 and Olivia and MT63 would be the throughput capability.  Olivia
and MT63 should be at least 4 times faster than MFSK16 but if you are direct
keyboard input, its the same.  

MFSK16 is by far the best keyboard mode but Olivia and MT63 the best file
transfer modes.

It is possible that there was more symbol interferrence for the MT63 mode to
decode but MFSK16 was able to...in this case it wasn't a signal level problem
as much as a propagation problem.  But that only a guess.

> 
> By the way, I think it was Rick Muething who recently made the claim that
> the SCS box was about 10 times the power of a Pentium Computer of today.
> Is
> that a reasonably true statement and explains why no one has been able to
> compete with the P modes?

I think that Curt answered that adequately and I will forward that response to
the MT63 group.

Thanks for the input and 73,

Walt/K5YFW

> 
> 73,
> 
> Rick, KV9U
> 
> 
> 
> -----Original Message-----
> From: linlink-bounces@wetnet.net [mailto:linlink-bounces@wetnet.net]On
> Behalf Of dubose@texas.net
> Sent: Wednesday, March 09, 2005 10:36 AM
> To: bcarling@cfl.rr.com
> Cc: flboatanchors@yahoogroups.com; cw@mailman.qth.net;
> linlink@wetnet.net; MOPAGROUP@yahoogroups.com; DCBOATANCHORS@topica.com;
> hamradioam@topica.com; MT63@yahoogroups.com
> Subject: Re: [MT63] 20 kHz wide Digital Proposal (Was: ARRL MUST GET
> BETTER)
> 
> 
> Brian,
> 
> Well yes and no.  What the HSMM is suggesting is that you allow up to 20
> KHz
> signals.  But we're taking about 56KBPs throughput that would allow one or
> more voice channels actually multi-mode all on one signal.
> 
> You might see 56KBPs data but it would only be on-the-air for a short
> time.
> The "channel" would be shared.
> 
> Right now we have MT63 at 200 WPM thoughput on a 2 KHz wide bandpass at a
> -5
> dB SNR on a poor CCIR channel.  But we really need to push 800-1200 WPM at
> the
> same signal level.  I don't see doing that with less than a 6 KHz channel
> even
> exploiting some of the new OFDM type modulation protocols being developed.
> 
> How many CW QSOs running at 20 WPM will it take to produce 1200 WPM error
> free
> copy at a signal level that MT63 can copy?  These are signal levels that
> even
> the best CW operator can't copy a signal at.  So the answer is that NO
> number
> of CW QSOs can produce the throughput of 1200 BPS, near error free, at a
> -5
> dB
> SNR on a poor CCIR channel.
> 
> All this  IS  possible if we are willing to step out of the box.
> 
> AND the new modes that will develop will be FAR SUPERIOR to Pactor III or
> anything being done today on HF.
> 
> We're also looking at doing much of this work using a computer sound card
> so
> separate controller hardware is not needed.
> 
> 73,
> 
> Walt DuBose/K5YFW
> Asst Chairman
> ARRL HSMM WG
> 
> 
> Quoting Brian Carling <bcarling@cfl.rr.com>:
> >
> > On 8 Mar 2005 at 19:11, David J. Ring, Jr. wrote:
> >
> > > I don't think the digital signals they want are 20 kHz wide!
> >
> > Want to bet on that?
> >
> > There IS in fact a proposal out now for a digiotal mode that IS 20
> > kHz wide for high speed data transefer on HF ham bands.
> > (as if Cra...  er, I mean Pactor is not jamming the HF bands enough
> > already!)
> >
> > Here it is:
> >
> > On Janauary 19, 2005, John Champa, K8OCL,ARRL Chairman, High Speed
> > Multimedia Networks Working Group, issued the Technology Task
> > Force report to the ARRL Board of Directors, which includes the
> > following:
> >
> > "At a minimum, 20 kHz wide emissions should be allowed in the
> > following segments:
> >
> >     3.58 - 3.725 MHz
> >     7.035 - 7.125 MHz
> >     14.065 - 14.15 MHz
> >     21.08 - 21.2 MHz
> >     29 - 29.7 MHz"
> >
> > Obviously, a *single* HSMM transmission, 20 KHz wide, could
> > totally wipe out all PSK31, MFSK16, RTTY, and many CW and DX
> > operations on 80m, 40m, and 20m, where they are now used
> > worldwide. Dozens of CW QSOS could be obliterated within
> > one 20 kHz swath. NOT a good idea at all!
> >
> > We have never seen such a lack of concern and compassion for the
> > majority of radio amateur activities as evidenced by the ARRL
> > Committee on HSMM and ARRL support for Winlink's attempted
> > domination of the HF frequencies, in both cases, to sacrifice the
> > hobby on HF for everyone else in order to favor a
> > very small special interest group.
> >
> > I can only hope that they really are coming to their senses at the
> > top level of leadership, but this is cause for alarm.
> > JIm Haynie says that they are going to have a new band plan by
> > July.
> > I hope it is a workable one that averyone can live with.
> > The Winlink/Pactor mess will hopefully get reined in by this.
> >
> > OK back to some fun CW contacts now, and a little less grumbling!
> >
> > 73 de AF4K
> >
> >
> >
> >
> > <<  Try MT63 on 80m - great fun!>>
> >
> > - The MT63 Reflector -
> >    MT63@egroups.com
> >
> > (To unsubscribe. send email to
> > MT63-unsubscribe@onelist.com)
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
> >
> 
> 
> 
> 
> _______________________________________________
> Linlink mailing list
> Linlink@wetnet.net
> http://wetnet.net/mailman/listinfo/linlink
> 
> 
> 
> _______________________________________________
> Linlink mailing list
> Linlink@wetnet.net
> http://wetnet.net/mailman/listinfo/linlink
> 
> 






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