[VHFcontesting] JT65 on 222 and above

Roger Rehr w3sz73 at gmail.com
Thu Apr 28 14:29:52 EDT 2016


Hi Patrick,

I would say, "Just get on and do it" :)

Don't worry about the frequency that you use; just stay out of the
beacon portion of the band, find a clear spot on your bandscope, and go
to it.

However, when you do so, make sure you "advertise" on ON4KST so folks
know that you are there.

You can also "advertise" on the JT4/JT65 Terrestrial Link, but that
won't buy you much due to very low utilization.  I think you
already know that...During the sprint last night the only stations on
the JT4/JT65 Terrestrial Link during the entire contest were you and
me.   

So ON4KST is the way to go.  I did not see you on ON4KST during the
sprint last night, and checking the History I don't see that you checked
in there either.  The link is www.on4kst.org.  

I spent a bit more than 30 minutes of last night's sprint calling CQ
using JT65b after advertising on ON4KST. There were no takers.  I likely
could have made more contacts by sticking to SSB and CW.  But I think
its important to establish a visible presence with the digital
modes...As more of us use the digital modes on these bands there will
be a snowball effect that will encourage more folks to use them.

Folks are beginning to understand that using the JT modes makes sense
for UHF and microwave work because it is equivalent to multiplying your
transmit power by a factor of ~10 (just as it is for VHF work), and so
terrestrial digital mode use is picking up on the UHF and microwave
bands although it is still way below the use on the VHF bands.
That is a shame, because if there were wider use we could likely extend
our completed-qso ring out one more grid square in all directions.

There were some stations last night with whom I couldn't
complete on CW.  Had they had digital capability, I suspect we would
have been able to complete.  This also occurred in the 222 Sprint last
week.

Hope the above is helpful to you Patrick!  Announce yourself during the
microwave sprint on ON4KST and see what you can do.  The 
combination of digital modes and Aircraft Scatter can lead to some
unbelievable distances!  I have some information on this at:  
http://www.nitehawk.com/w3sz/AircraftScatter.htm

A paper that I presented in 2014 on using AS for the Microwaves is at:
http://www.nitehawk.com/w3sz/W3SZ-NEW-AirCraftScatterNEWS2014.pdf

You are 665 km from me in FN20ag.  My longest CW contact last night on
432 was 684 km, and Aircraft Scatter was needed for completion. On the
higher bands we'd likely need to make use of both AS and the digital
modes to have a chance of completing.  My AircraftScatterSharp program
allows you to enter pertinent station characteristics for the station
at each end of a potential QSO, click on a spot where an aircraft might
be [or on a real one if present at the time you are checking] and see
what the signal margins are. So you can test the likelihood of
completing a contact beforehand.  

So I strongly encourage you to get on ON4KST and on the air and give it
a try during the Microwave Sprint!  I will be doing the same :)

73,

Roger Rehr
W3SZ

On Thu, 28 Apr 2016 13:14:48 -0400 (GMT-04:00)
Patrick Thomas <p-thomas at mindspring.com> wrote:

> I'm not aware of an established frequency for JT65 on 220 or higher
> bands.  I really wanted to try yesterday around 432.076 yesterday
> (consistent with the .076 everywhere else) but chickened out as the
> frequency is designated for "weak signal work" and although JT should
> technically qualify, I'm not sure whether AFSK modes are appropriate
> there.  Then again I guess nobody complains on the other bands where
> it's interspersed with CW.
> 
> Should I just start operating there and hope it catches on? :)
> 
> I could see this being of some value for the microwave sprint as
> well, although unless I find a 33cm transverter in a hurry my only
> option for JT will be 10w on 23cm via the TS-2000X.
> 
> By the way, I only made 3 QSOs last night but I'm not complaining
> given my QTH.  Thanks to WW8M, K8CC, and W8RU for being out there!
> And for putting up with my rusty contesting.  As much as I love it,
> banging out my old novice call makes me wish the FCC would pick me
> for one of those 1x2 calls one of these days.  Still bitter that I
> missed out on AI8E. ;)
> 
>  - Patrick / KB8DGC
> 


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