Jay: The argument that SSB is so much faster than FT8/4 and stations should
switch to SSB when the band is open is not universally true. It is if you
are the station running guys on a specific frequency, but NOT if you are
one of the poorer equipped calling the running station. When running low
power, it will often take 10 or more minutes to work a station on SSB when
the band is open -- I am competing with many stations with better signals
than me. But, on FT8/4, everyone gets decoded, and my rate actually goes
up. --Mike, WV2ZOW
On Thu, May 2, 2019 at 1:48 PM Jay RM <w9rm@calmesapartners.com> wrote:
> The 'need for FT speed' reflects the huge QSO/hour disadvantage FT8 has vs
> SSB when the band is open. Many 6M op's have foolishly abandoned SSB
> during contests, so the introduction of FT4 is an attempt to speed things
> up a bit. We'll see whether the mode can ultimately live up to it's
> promise. With all the mouse movements and click-click required, I doubt
> FT4 will perform anywhere near as well as an experienced human op using
> SSB. We will see.
>
> Remember, FT4 is advertised as a 'contesting' mode. The idea of a contest
> is to maximize your score. The best way to maximize a score is to run
> contacts as fast as possible over the duration of the contest. So, one
> should use the fastest mode for the given conditions. When the band is
> closed or marginal, you want to use the most sensitive mode. This could be
> JT65 if the potential contact base is limited or FT8 if there are many weak
> stations to work (or CW, of course). As the band opens, there will be a
> point where the intelligent operator needs to make a switch from
> 'sensitivity' to 'speed'. Should this switch be FT8 to FT4 ? No, because
> SSB is faster and certainly sensitive enough during a Es opening.
>
> If this is the case, why does FT4 really exist as a contest mode ? It's
> not as good for weak signals as FT8 and it's most likely not as fast as
> SSB. "Because we can" is not a sufficient answer for something that has
> shown the capability to totally upset the status quo of an entire band in a
> negative way (condensing an entire band full of operators on to what is
> realistically one frequency).
>
> -W9RM
>
> Keith Morehouse
> via MotoG
>
> On Thu, May 2, 2019, 10:59 AM Mark Spencer <mark@alignedsolutions.com>
> wrote:
>
> > It is interesting to me that the new JT modes seem to be emphasizing
> > speed. From my perspective I view the digital modes as a means of
> > completing qso's that can't be done with traditional analog modes and am
> > happy to trade off speed for better weak signal performance. Or I like
> > really fast modes that can exploit brief propagation modes such as meteor
> > scatter outside of a major meteor shower.
> >
> > That being said the activity levels where I live are low enough that if I
> > manage to work more than 10 stations while activating a rare grid in VE7
> > land I consider the trip to be a great success (: So my perspective may
> > be a bit unusual (:
> >
> > I'll be curious to see how this new mode works out in practice. I
> > appreciate the efforts of the developers and early adopters / testers.
> >
> > In the mean time I am expecting to use JT9 on 50 MHz this season.
> >
> > 73
> > Mark S
> > VE7AFZ
> > mark@alignedsolutions.com
> > 604 762 4099
> >
> > > On May 2, 2019, at 9:29 AM, Aa4zz via VHFcontesting <
> > vhfcontesting@contesting.com> wrote:
> > >
> > > Per Joe Taylor's talk at the VHF Super Conference
> > > The faster speed comes with a trade off of 4.5db less sensitivity.
> > > Of course for many QSO's that will not matter, but on weak signals it
> > may.
> > > 73 Paul AA4ZZ
> > >
> > >
> > >
> > >
> > > Message: 1
> > > Date: Mon, 29 Apr 2019 10:47:01 -0700
> > > From: Brian Dickman <brian.dickman@gmail.com>
> > > To: VHFcontesting@contesting.com
> > > Subject: [VHFcontesting] FT4 mode
> > > Message-ID:
> > > <
> > CAJnrbTwEcfmp0MVKXZV7kSc8OFhvTK9w-4YVE+hUHu_mvveMzg@mail.gmail.com>
> > > Content-Type: text/plain; charset="UTF-8"
> > >
> > > Since the topic hasn't appeared on this list yet, I figured it would
> be a
> > > good idea to make folks here aware of the pending WSJT FT4 mode in case
> > > they hadn't seen it already.
> > >
> > > The tl;dr:
> > > * 2.5X faster than FT8
> > > * Same contesting features as FT8
> > > * Automatic search and pounce mode
> > > * 144.170MHz proposed 2m frequency
> > >
> > > To read more, here's a couple links:
> > >
> > > *
> > >
> >
> http://www.arrl.org/news/faster-more-contest-friendly-ft4-digital-protocol-to-debut-in-a-week
> > > * http://physics.princeton.edu/pulsar/k1jt/FT4_Protocol.pdf
> > > *
> > >
> >
> http://www.southgatearc.org/news/2019/april/video-of-ft4-talk-by-joe-taylor-k1jt.htm#.XMc36OhKhaQ
> > > (video
> > > of a club talk Joe Taylor made about FT4)
> > >
> > > 73,
> > > --
> > > Brian AF7MD
> > >
> > >
> > >
> > >
> > > ------------------------------
> > >
> > > Subject: Digest Footer
> > >
> > > _______________________________________________
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> > > http://lists.contesting.com/mailman/listinfo/vhfcontesting
> > >
> > >
> > > ------------------------------
> > >
> > > End of VHFcontesting Digest, Vol 197, Issue 2
> > > *********************************************
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