Hi Grant,
thanks for taking the time to look at possibilities for FT4 band slots.
Comments in line below.
On 26/04/2019 12:15, Grant VK5GR wrote:
Joe et al,
A word if I may about frequency choices. Some of those proposed for FT4
probably leave a bit to be desired. Here are some thoughts to consider:
80m 3.595 - PROPOSE 3562kHz - 3595 is completely out of band for JA
completely and into the phone part of the band outside of Region 2. My
suggestion based on occupancy and proximity to existing digital sub-bands is
something around 3562kHz (at least keeping away from 3560 which is sometimes
a CW QRP frequency). While the IARU band plans currently have digital as
3570-3590kHz a case can be made for expanding that - and given other
restrictions in some countries on 80m, expanding digital down at least 8kHz
to 3562kHz makes some sense. A case to be made for the IARU - but you can
"help" their decision by starting to use it anyway. BTW 3600kHz is the
centre frequency for IARU R3 80m disaster comms - LSB - so FT4 on 3595 USB
will badly clash with that - another reason not to use 3595.
3562 kHz is a problem in both regions 1 and 2 as it is below the narrow
band digital mode sub-band which starts at 3570 kHz. The only overlap
with JA and the rest of the World is 3570 - 3575 kHz which is
effectively 3570 - 3573 kHz if we assume USB and a 2 kHz wide slot.
Having looked at as many bad plans as I can find I can only suggest 3590
kHz with an alternate of 3568 kHz for region 3. 3586 kHz is probably
considered as RTTY territory so even that is not free of contention.
40m 7.090 - PROPOSE 7052kHz (inside the digital sub-band) or 7062kHz (just
above the digital sub-band noting it is heavily used for SSB at least in
region 3) - 7090 only makes sense in the USA! Many other countries have this
as SSB voice use. The IARU digital segment is (depending on region)
7040-7060 or 7040-7060. With 7056 already being used for FT8 F/H mode on a
fairly regular basis it would make sense to use say 7050 or 7052kHz instead.
Note that 7090 is the designated SSB QRP frequency. I would promote 7050 for
FT4. The only reason not to is that the RTTY guys if FT4 and RTTY are in the
same contest might object - but during the contests the RTTY guys spread out
and use anything from 7030 to 7120 anyway in complete disregard of the band
plans. If they are going to be that unruly then putting FT4 down there
doesn't seem all that bad.
7052 kHz is in the wide band digital mode section for region 1 and
region 2 which allows packet and related modes where there are automatic
stations active, so may not be compatible. As far as I can see 7047 kHz
looks a reasonable choice with the main criteria being below the 7050
kHz upper limit for narrow band digital modes in regions 1 and 2.
********* 30m / 17m / 12m - should NOT have FT4 allocations at all. FT4 is a
CONTESTING mode and CONTESTING is by global agreement excluded from those
WRC79 bands!!! *********
FT4 is capable of the exact same operation style as FT8 and I doubt we
will limit its use to contest modes only. the 30m, 17m, and 12m proposed
suggestions are the same as currently used for JT9/JS8CALL, we are not
encouraging increased bandwidth use on those band. If usage grows the
working frequency suggestions can be revised later.
20m 14.140 - PROPOSE 14062kHz - the original proposed use of 14140KHz again
is well outside the digital segments where FT4 belongs. If anything,
creeping down into 14060-14070 might be considered acceptable despite not
being in the band plan if the aim was to separate RTTY and FT4 users in the
same contest. Going high above 14.112 (the acknowledged edge of the global
20m digital band plan segment) will be frowned upon. Take a leaf from 80m
and use 14062kHz - again at least that keeps it away from the CW QRP Centre
of activity and meets the objective of separating it from RTTY.
14062 kHz is below the lower limit for narrow band digital modes in all
three regions at 14070 kHz. 14080 kHz is the best alternative I can come
up with. It is in RTTY territory again but I don't see anything better
below 14099 kHz.
15m 21.140 - PROPOSE 21062kHz - follow 20m and choose 21062kHz - although
21140kHz is the first proposed FT4 frequency that fell inside a digital
subband...
I don't see any issues with 21140 kHz and you are the first to suggest
an alternative. What is your objection to 21140 kHz?
10m 28.180 - POROPOSE 28062kHz - again follow 20m
I don't see any issues with 28180 kHz and you are the first to suggest
an alternative. What is your objection to 28180 kHz?
6m 50.318 - PROPOSE somewhere below 50.313 not above. Moving above is just
moving further into several countries beacon segments. Not likely to get a
lot of airplay as a international contesting band for FT8 so not as critical
- but my suggestion would be look below 50.313 not above.
I don't understand why countries like VK are putting beacons in the 50.3
- 50.4 MHz range, I thought International coordination of 6m was moving
all propagation beacons to 50.4 - 50.5 MHz.
For discussion folks.....
Regards,
Grant VK5GR
WIA Appointee to the IARU Region 3 Band Plan committee
So in summary, I am suggesting amending our proposed suggested
frequencies for FT4 to:
*3595 kHz all regions 1 and 2**
**3568 kHz region 3*
*7074 kHz all regions*
10140 kHz all regions - shared with JT9 and JS8CALL
*14080 kHz all regions*
18104 kHz all regions - shared with JT9 and JS8CALL
21140 kHz all regions
24919 kHz all regions
28180 kHz all regions
50318 kHz all regions
Further thoughts?
73
Bill
G4WJS.
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