[CQ-Contest] IARU HF zones

Michael Keane, K1MK k1mk at alum.mit.edu
Thu Jul 8 04:35:50 PDT 2010

I'd thought this would be a recurring subject but not that it would 
recur quite so soon :-)


Once again the present confusion results from the "ITU zones" as 
referenced in the IARU HF Chamionship Rules are really the "ITU Zones as 
adapted for use by amateur radio operators" (see for example Chapter 
10.10 in the IARU R1 HF Managers Handbook 
and NOT the actual ITU HFBC CIRAF zones.

As Jim VE7FO suggested, life we would be a whole lot simpler if we 
referred to the zones that we use in the IARU contest as IARU zones and 
not ITU zones :-)

AFAIK, no one has ever published a map of these IARU zone, i.e. the "ITU 
Zones as adapted for use by amateur radio operators". Every map to which 
I've ever seen a link (including the one on the IARU contest rules page) 
is a really map of the ITU HFBC CIRAF zones, illustrative but not 

Mike K1MK

On 7/8/2010 1:13 AM, Milt, N5IA wrote:
> Hmmm. Inquiring minds want to know.
> I am located in NM with the 109th meridian being my east property line.  The
> AZ state line is 3 miles to the West.  Some are pointing out that the ITU
> Zone 7 extends to the 110th meridian, about 80 miles to the west.  Others
> say,and some maps seem to indicate, that the AZ/NM state line is the
> boundary between Zone 6 and 7.  Also, it appears from some maps that being
> this close to the border with Mexico might put me in Zone 10.
> With regards to comments that have been flowing on the contesting.com
> reflector, the map in this link provided by Dave, AB7E, who would definitely
> be in Zone 10,
> http://www.itu.int/ITU-R/terrestrial/broadcast/images/broad-namer.gif
> indicates there appears to be a conflict with what some are saying about the
> ITU zones, in that boundaries of the zones are being drawn along the Lat and
> Lon lines.
> This map seems to show the zones following state lines and the international
> border with Mexico.
> http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=12892
> The map in the following link shows the zones boundaries following Lat and
> Lon lines with some diagonal take offs from those and that the international
> boundaries either in the North with Canada or in the South with Mexico are
> not necessarily the zone boundaries.  Look at the state of Washington and
> around the Great Lakes.
> http://www.mapability.com/ei8ic/maps/itu-zone.gif
> Also, written descriptions that Dave, AB7E, points out mention east to west
> divisions.......
> 6. W6, W7 (excluding Wyoming&  Montana east of 110W)
> 7. W5 (excluding Mississippi), W7 (Wyoming&  Montana east of 110W), W0
> 8. W1, W2, W3, W4, W5 (Mississippi only), W8, W9, 4U (New York)
> but has nothing to say about north to south divisions.
> And the full descriptions at the other site Dave, AB7E, points to have the
> following which reference Longitude lines and not state lines or
> international boundaries..........
> 06          W-K-N-A   U.S.A. (Washington, Oregon,
>                        California, Nevada, Idaho,
>                        &  that part of Montana,
>                        Utah&  Arizona west of
>                        110 Deg. W.)
> 07          W-K-N-A   U.S.A. (N. Dakota, S. Dakota,
>                        Nebraska, Wyoming, Colorado,
>                        New Mexico, Texas, Oklahoma,
>                        Kansas, Iowa, Minnesota, that
>                        part of Utah&  Arizona East
>                        of 110 Deg. W.,&  that part
>                        of Michigan, part of Montana
>                        Illinois, Missouri, Arkansas,
>                        Tennessee, Mississippi,
>                        Louisiana&  Wisconsin west
>                        of 90 Deg. W.)
> 08          W-K-N-A   U.S.A. (Indiana, Alabama,
>                        Georgia, Florida, Virginia,
>                        Kentucky, N. Carolina, S.
>                        Carolina, West Virginia,
>                        Maryland, Delaware, Ohio,
>                        Pennsylvania, New Jersey, New
>                        York, Maine, Connecticut,
>                        Rhode Island, Massachusetts,
>                        New Hampshire, Vermont,&
>                        that part of Michigan, Illinois,
>                        Missouri, Arkansas, Mississippi,
>                        Tennessee, Louisiana&
>                        Wisconsin east of 90 Deg. W.)
> I agree with Dave, that someone, somewhere, sometime needs to declare once
> and for all where the actual zone boundaries are located.
> Mis dos centavos.
> de Milt, N5IA
>> On 7/7/2010 4:44 PM, RT Clay wrote:
>>> Actually, getting the precise zone is quite important because of the
>>> zone-based scoring (1 pt same zone/3 points other zones). I bet that if
>>> you are in zone 10, your score will be higher by 15-20% compared to zone
>>> 6.
>>> In the past, the ARRL had a list which precisely defined what parts of
>>> which states were in which zone. No part of AZ was in zone 10 ! It seems
>>> that the list was removed when the ARRL website was revamped, but you can
>>> still get it at:
>>> http://web.archive.org/web/20070318210126/www.arrl.org/contests/vev0vy.html#wkna
>>> Then I found
>>> http://www.arrl.org/contest-update-issues%3Fissue%3D2010-06-09
>>> which references a map
>>> http://www.itu.int/ITU-R/terrestrial/broadcast/hf/refdata/maps/index.html
>>> and "corner coordinates" at
>>> http://www.itu.int/ITU-R/terrestrial/broadcast/hf/refdata/reftables/ciraf.txt
>>> But I think those are actually "test points" for evaluating signal
>>> strengths, and not on the boundaries of zones. If you plot some of them
>>> (for example the SW quadrant of zone 8 where I am), you will see they are
>>> not at all the boundaries. Also notice for example that the east boundary
>>> of zone 7 does not correspond to the west boundary of 8 in that list.
>>> So which one should we use? I'd be happy to put myself in zone 7
>>> according to the "corner coordinates" referenced and get a 20% increase
>>> in score :)
>>> Tor
>>> N4OGW/5
>>> --- On Wed, 7/7/10, David Gilbert<xdavid at cis-broadband.com>   wrote:
>>>> From: David Gilbert<xdavid at cis-broadband.com>
>>>> Subject: Re: [CQ-Contest] IARU HF zones
>>>> To: cq-contest at contesting.com
>>>> Date: Wednesday, July 7, 2010, 12:38 PM
>>>> I don't believe that the precise ITU zone borders are what
>>>> the contest
>>>> sponsors expect you to use.  If they were, I would be
>>>> in zone 10, not
>>>> zone 6.  Besides, how could anyone actually know what
>>>> zone they are in
>>>> if they were close to a line that didn't follow a political
>>>> border?
>>>> I've seen some pretty detailed official ITU zone maps but I
>>>> still can't
>>>> determine exactly where the dividing line is as it crosses
>>>> southern
>>>> Arizona.  Even if I could find the coordinates for the
>>>> endpoints of the
>>>> ITU boundary lines, I'd have to calculate the coordinates
>>>> for any other
>>>> point on the line.  I seriously doubt anyone expects
>>>> us to do that.
>>>> Yes, we all should copy what is sent, but when someone
>>>> doesn't send what
>>>> they are supposed to it creates needless confusion.
>>>> In my opinion, you
>>>> needlessly bring that lost QSO rate upon yourself.
>>>> I've sent an email to KX9X asking him to clarify this issue
>>>> for the
>>>> upcoming IARU contest and maybe he will reply.
>>>> 73,
>>>> Dave   AB7E
>>>> On 7/7/2010 6:22 AM, Joe wrote:
>>>>> But since 1977  I'm now in Wisconsin,  But
>>>> in Zone 7!  But many assume
>>>>> being a 9 land Call and in Wisconsin, MANY assume that
>>>> the border is the
>>>>> state line, and it is not!  I bet I easily in
>>>> this contest loose a 10%
>>>>> QSO rate confirming that I'm in 07 NOT 08.
>>>> Grrrrr,

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