At 02:38 PM 6/30/06, Richard Ferch wrote:
>If it was, how on earth is someone living in Latvia, Lithuania,
>Belarus, Ukraine or Moldova supposed to determine which side of the line
>they are on?
I would presume in a similar fashion to how they determine the
Maidenhead grid square in which they're located, a task that many
hams seem to have mastered.
>Can anyone seriously think that the crazy combination of oblique
>lines running right
>through the middle of several countries on that map was meant to be taken
>literally?
For the purposes these zones were created, yes the zone boundaries
were meant to be taken literally and still are. It was never intended
for the CIRAF zone boundaries to accurately follow any past or
present boundaries, political or physical; that would be a totally
unnecessary complication for their intended use. The ITU broadcasting
(CIRAF) zones have been in use for 50+ years and have always been
defined as a set of polygons specified by the latitudes and
longitudes of their vertices.
>I note that every QSL card I have ever received from anyone in UA2 that
>specifies an ITU zone says ITU zone 29, despite the fact that the CIRAF map
>places all of UA2 on the zone 28 side of that line.
UA2 being in Zone 29 is something that's specified in the IARU R1
interpretation of the ITU zones (see below)
>Similarly, it seems reasonable to suppose that the border between zones 27
>and 28 was intended to include all of France and the Benelux countries in
>zone 27. Every QSL card or LotW confirmation I have from F, ON, LX or PA
>that specifies an ITU zone says zone 27, regardless of what the CIRAF map
>would imply.
Likewise and in the ARRL list that you cite
>The CIRAF map and the ITU zones were originally set up to allow
>broadcasters to specify who their target audiences were. For that purpose,
>it is national and linguistic boundaries that make sense, not arbitrary
>straight lines drawn helter-skelter on a small scale map.
The CIRAF zones were created and remain in use to facilitate
frequency coordination amongst international broadcasters. As radio
propagation doesn't respect national and linguistic boundaries, the
purpose of the zones is to designate the general target area of a
broadcast not necessarily the specific target audiences.
The coordinates at the center of each zone, and certainly the
coordinates at the centers of the quadrants of each zone, provides
sufficient granularity to match the spatial resolution of propagation
prediction codes. For the purpose of determining coverage contours
and interference potential, predication are always made for the
target zones as well as for neighboring zones. So the fact the CIRAF
zones don't align perfectly with the political or linguistic borders
of the target is very much an irrelevant detail.
Somewhere along the line, perhaps with the first IARU Radiosport
Contest in 1977 perhaps prior to that, the CIRAF zones were grafted
onto Amateur radio. It certainly wasn't a perfect fit, as you've described.
Modifying the CIRAF zones to bring the zone boundaries into
coincidence with political boundaries certainly makes the "ITU zones"
much more "user friendly" than would using the literal CIRAF zones.
>How does the ARRL define ITU zones? On its contest web pages, in
><http://www.arrl.org/contests/announcements/prefixtable.html> and
><http://www.arrl.org/contests/vev0vy.html>. For the purposes of the IARU
>contest, in case of disagreements between a map (any map) and the
>definitions on the ARRL web pages, what takes precedence? The answer should
>be obvious.
The IARU R1 HF Managers Handbook
<http://www.iaru-r1.org/HF%20HANDBOOK.htm> includes a similar table,
listing the correspondence between "ITU zone" and country/prefix
contained therein.
These tables are really what define the "ITU zones" as they has come
to be commonly used in Amateur radio. Although based upon them, the
"ITU zones" to be used next weekend in the IARU HF Championship are
not identical to the CIRAF zones. All the maps for which pointers
have been posted so far show the boundaries of the CIRAF zones, not
the "ITU zones" that we use in Amateur radio.
73,
Mike K1MK
Michael Keane K1MK
k1mk@alum.mit.edu
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